GEOL. CROAT. 51/2 135 - 162 3 Figs. 1 PI. ZAGREB 1998 

Problems for Evaluation of the Scenario of the Permian -Triassic Boundary 
Biotic Crisis and of Its Causes 

Heinz W. KOZUR 

Key words: PIT boundary, Biotic crisis, Extinction 
and recovery patterns, Volcanic winter, Superano­
Xla. 

Abstract 
Determination of the causes o f the Permian -Triassic boundary 

(PTB) biotic crisis is hindered primarily by the diachronous nature of 
the used PTB, poor stratigraphic control of compared Upper Permian 
and Lower Triassic faunas, espec ially in cont inental biotopes, poor 
knowledge of the lower and midd le Scythian faunas from m,UlY envi­
ronments, and by interpolation of the unknown (lower and middle) 
Scythian diversity from the known Upper Pennian and Middle Trias­
sic diversity data in many major fossil gro ups. Most of these prob­
lems can be reso lved by using the firs t appearance datu m (FAD) of 
Nil1deodlls pan'Ii,I' as either an isochronous PTB, or as an isochronous 
marker [eve I very dose 10 lhe base of lhe Triassi c; careful studies of 
fossil-rich, comp[ele conlinental boundary sections (e.g., Dalongkou 
in Sinkiang), and uti li sation of uninterpoJated diversity data, which 
are based on known Scythian data, for the reconstruction of the 
extinction and recovery patterns in all fossil groups. 

The most important features of the PTB biotic crisis arc: (I) 
Among the marine biota, only the pl ankton and the wann-water ben­
thos, nektobenthos and nekton are strongly affected by the PTB biotic 
crisis . (2) The recovery of the warm-water nekton and nektobenthos 
was very fast (after one conodont zone). The recovery of the warm­
water benthos, some of the plankton (radiolarians) and the terrestrial 
plant product ivity was strongly delayed for several million years, and 
occurred on ly in the upper Olenekian (upper Scythian) and in the 
Middle Triassic. (3) The number of the Lazarus taxa that re-appeared 
in the upper Olenekian and above all in the Middle Triassic, is very 
high (about 50%) and in some fossi l groups 90-100% at generic le­
vel. 

The reconstruction of the scenario for the PTB biotic crisis 
requires not only the cons ide'rlItion of the uninterpolaled extinction 
and recovery patterns of all foss il groups across all envi ronments, but 
must also account for the main feat ures of geological evolution from 
the Middle Permian to the Lower Triassic. The most important causa l 
factors in the PTB biotic crisis are the ex tinction event at the 
Guadalupian- Lopingian boundary that restricted the diverse Upper 
Permian wann-water benthos 10 the Tet hyan shelves, the long-[asling, 
widespread Siberian Trap volcanism (Dzhulfian - lower Scythian) 
which was Ihe grealest volcanic event during the Phanerozoic, and (he 
very strong explosive felsic 10 intermediate volcanism around the 
PTB, close to the margin between eastern Tethys and Panlhalassa. 
These volcanic activities resulted in those climatic changes that were 
dircclly and indireclly (as cause of the oceanic sll peranoxia) responsi ­
ble for the PTB biotic crisis, such as periodic cooling of Ihe climate 
by volcanic dust and sulphate aerosols (mai nly caused by the Siberian 
Trap volcanism), acid rain, a 3-6 month "vo[canic winter" at low lat i­
Illdes and Ihe strongly reduced inpul of sunl ight during the uppennost 
Dorashamian (both caused by lhe very strong explosive volcanism at 
the Tethys/Panthalassa margin), followed by global warming in the 
lower Scythian, and uppennost Dorashamian to lower Scylhian super­
anoxia . 

Rezsti lI. 83, H-[029 Budapest, Hungary. 

1. INTRODUCTION 

The search for the causes of the biotic crisis around 
the Pennian- Triassic boundary (PTB) requires the inve­
stigat ion of the exact scenario of the PTB biolic crises 
(extinction and recovery patterns among all major fau ­
nal and floral groups of all facies) and the exact g lobal 
correlation of these patterns. It also requires considera­
tion of accompanying geological phenomena (e.g., 
faci es changes, climatic changes, age and character of 
volcanic activity around the PTB, changes in stable iso­
topes, the distribution and vertical range of the oceanic 
anoxi a) . These investigations have been hampered by 
(1) incorrect correlation of the PTB in different faunal 
realms and facies; (2) erroneous assignment of strong 
bi otic changes at diachronou s facies boundaries to the 
PTB biotic changes; (3) erroneous assignment of strong 
biotic changes, occuring between Permian and Triass ic 
continental biota that are separated by a long time gap, 
to the PTB biotic crisis; (4) comparison of Permian and 
Triass ic faunas with poor st ratig raphi c control; (5) 
inadequate knowledge of the lower and middle Scythian 
pelagi c faun as; (6) interpolation of the unknown or 
poorly known (lower and middle) Scythian diversity of 
major fossil groups from known Upper Permian and 
Anisian diversities. 

In the present paper some of the problems in the 
search fo r the real extinction and recovery patterns and 
the most important features of the PTB biotic crisis are 
indicated. On the basis of the real (not interpolatcd) 
ext inction and recovery patterns of the major fossil 
groups, and with consideration of the geological phe­
nomena in the Upper Permian and Lower Triassic, a 
possible scenario for the PTE biotic crisis is presented. 

2. POSITION AND CORRELATION OF 
THE PERMIAN -TRIASSIC BOUNDAR V 

The following leve ls are, partly for historical rea­
sons, the most important PTB levels used in marine and 
continental beds: (1) the base of the Buntsandstein in 
the southwestern Germanic Basin; (2) the boundary 
bctween the Bellerophon Limestone and the Werfen 
Group in the Southern Alps; (3) the base of the 010· 

ceras woodwardi Zone in eastern Perigondwana; (4) the 
basc of the Otoceras concavum Zone in the Arct ic; (5) 
the first appearance datum (FAD) of Lystrosaurus in 



136 Geologia Croatica SI/2 

Himalaya Meishan Selo n9 South. Alps Greenla nd Arctic Canada Germanic Basin 

Prio nolobus , 
G rotu ndatus , 

Bernburg Formation a , 
n , Siusi U. brevifor mis 
d 

I Pleura gyronites 
Member Cornia ger mari V. sverdrupi 

a Pie urogyr. 
K' I 'd B, rsatus 

, 
pia nidorsatus , a l p ani 0 , S , P. candid us 

ca 
, n' , red, above 

yh 
, 9 , 

Iimnic, below 
T y' s' 

Andraz 
P. rosenkr antzi C, 

mostly sabkha 
Ha i, 

h' B. strigatus a' 
In G a' Horizon I, 

Op hiceras n l rlOphice 'as W. decipie ns 
Ai a 

tibe ticum k I e I tibeticu m 
(evaporitic) ~: Sandy Claystone 

Nan 
8 1Boundary Bed ~ I rI Member n9 n, F' 

- - - --
e d, 
t 9, m' Oph. com mune Oph. comm. e' 
i , 
a F , , F, variegated 

O. woodwardi o,d 10. woo dwardi n Mazzin 0' ',- Boundary 
Member T. pascoei I " m,c Bed 2 , O. "Iati lobatum" a, , 

a' I-
II ., 

I I a+b 
M. subdem Otoeeras i I Clayey Sandstone 0 ISS -

D 0' n, H martini boreale 5.1. nl Member 
0 I Boundary Bed 1 

J ("Graubank Zone") , 
250 my-a 

, ~ , 
s Ooille Hypoph. tr Male , 
h 

, 
a 

O. B'bCkel~~ Llrr concavum 
Changxing I 

.. 
0' schiefer 
p a Limestone ? 7 S.s. 
I n 

lfill 
N 6 
G 

l-I 
A Bellerophon 5 
ND Limestone I-

z Formation 4 h 
u Kul ing Longtang ~ Zechstein 
I For mation Formation 3 
f 
i I-
a 

Schuchert 
2 

n l-

n Dal Forma tion spiculitic 
chert 1 

1a 
Fig. I COITelation chart of some important marine and continental successions. Detailed on ly around the PTB. Vertical scale not thickncss- or 

time-related! The upper Capitanian part is on ly shown for the Ru ssian Platfonn and the Timan-Petchora Basin. After BAUD et aL ( 1996), 
CHENG el at. (1989), JIN el at. (1996), KOZUR (1989. 1994b, 1996b), KOZUR & SEIDEL (1983), KOZUR cl at. (1996b), KRYSTYN & 
ORCHARD (1996), LOZOVSKV (1993), LUCAS ( 1993), PERCH·NIELSEN el at. (1974), RENNE el at. (1995), SADOVNIKOV & 
ORLOVA (1993), TEICHERT & KUMMEL (1976), TOZER (1967), TUZHIKOVA (1985), XIA & ZHANG ( 1992), YIN cl at. (l996a, b). 
Figure la: Marine sllccess ion and Germanic Basin (marine and continental, PTB continental); Figure Ib (opposite page): Continental suc­
cessions and Germanic Basin. Legend: ..... = Used Pff boundary (FAD of Hindeodlls parl'US in marine beds). The following abbrevia­
tions are used unly in Figure I b: G = Uppennost Guadalupian Series; C = Upper Capitanian Stage; Gill m = III m above the base of the 
Ouodikeng Fm. in the Dalongkou section etc. Measurement after LUCAS (1996, during a joint project sponsored by the NOS, USA); 1 200 
m = 200 m above the base of the liucaiyan Fm. in the Xiao!ongkou secti on. 

conlinental beds; (6) the FAD of Ihe conodont Hindea· 
dus parvus (KOZUR & PJATAKOVA). These different 
PTB levels are moslly equated with each other, but are 
by definition situated at different stratigraphical levels. 

The base of the Buntsandstein in SW Gennany, the 
priority base of the Triassic (von ALBERTI, 1834), is a 
diachronous facies boundary within continental beds 
(KOZUR, 1994b, 1998a) which is only of historical 
interest. It has it s lowest position at the margin of the 
Germanic Basin (including the Triassic type area in SW 

Germany), where Zechstein equivalents of the central 
Germanic Basin , such as the Brockelschiefer, Leber­
schiefer and Tigersandstein were included in the 
Buntsandstein, but also lies in Upper Permian Dora­
sham ian Stage within the centre of the Germanic Basin 
(Figs. la & b). 

The base of the Werfen Group (base of the Tesero 
Oolite) was equated with the base of the Triassic in the 
Germanic Basin and placed at a level where the diversi­
ty of a rich Upper Permian fauna and marine flora of 



Kozur: Problems for Evalualion oflhe Scenario of Ihe Pennian-Triassie Boundary ... 137 

Oalongkou-Xlaolongkou (Tianshan) Germanic Basin 
~~----t-----+'-,------~-----------+----------r---------,--------------~ 

G Bernburg Formation : I 

Russian PiaU. Timan-Petchora Sa. Siberian Platform 

a Krasnobakovs~ 1 Supra-Basaltic Beds 1 
n 'Member 1 
d ' , 
a I VI 1 

B r I Ol'---____ --h not investigated 1 
S r Cl red, above kl 1 
C a a l limnic, below hi I 
Y h II I 
T V 

I mostly sabkha ml 1 ;, 
HaG 6 1 al Ryabinsk 1 

l? a d:sandy Claystone nl Member 1-_____ : 
N a ~ elMember _ - - . F: J 200m I - LAD Lystrosaurus and 

n e 1 01 Ustkelterian Fm. Jiucaiyan I Falsisca 
t FI . d r I Formation " " 0 t variegate Cc---,----rrn 

ml Astashich , U.LU.J..LLLl.LU.!..LLU.'-4 ______ -1 a rl al I G 234.7m --, 
n ml I I Mbr. G 219m I, - LAD Dicynodon .' . , " 

~ I 01 
IIClayey Sandstone nl 

o ~IMember : 
1("Graubank Zone" , ' , o 

basalts 

Marininskian Fm. 

Puturanian 
basalt 250my 

G210m 

G171.2m 
G 161m 

, 
, 
I - FAD Falsisca verchojan. 
I - LAD Falsisca postera 
, 

a 

• h 
Brockel=UW I 

________ - i-----------1T 
• 

I - FAD Lystrosaurus , , 
a 

L . 
0' 
pa 
I n 
N 
G 
I 
AD 
Nz 

h 

_. schiefer U 
7 s.s. 
I--
6 
l-
S 

I--
4 

u r- Zechstein 
I 3 

intra-basaltic Beds 
(basalIs with 
sedimentary 
intercalations) 

sub-basaltic Beds 

, ; 
, m 

t, Y 
u, r 
fl i 

" . al Hunglukunian n 
c 1 Formation ., 
0, 

S 
t 

u, • 
" 9 , . 

Guodikeng: - FAD Falsisca postera? 
Formation 1 - FAD Falsisca eotriassic 

G 111m ' 
G 107m 

, 
I - LAD Megasitum, 
I Bipemphigus, 
I Tripemphigus 

' I--! 2 
mTTl"TTrTTTTl"TTrrrrrl

s 
1- - - - - - -

~ 1 Lebedevian 

, , , , , , 
n I--

1 

i l Fm. ., G6Sm I - First Falsisca in the 

II I II I I 

I111 1111111111 

upper Tatar. 
U.J..L~1.U.LULU.1.U.LU.J..LLt..Js I Tutontchan. 

I Guodikeng Formation 
1------- ,1 and in Siberia , 

Wutonggou Fm. I , GC (Vjatka) upper T atarian 

Ihe Bellerophon Limestone Formation suddenly drops 
to a very low dive rs ity fauna and flora of the Tesero 
Ooli te. However, as shown by KOZUR ( 1994b), thi s 
boundary is also a diachronous facies boundary within 
the Upper Pennian. The decrease in diversity is caused 
by the change from a highly diverse shallow-water 
shel f community into a low-diversity tidal flat commu­
nity. Such facies change is always accompanied by a 
drastic decrease in diversity, independent of the strati ­
graphic level within the Pennian or Triassic. 

The base of the Triassic at the base of the Werfen 
Group is also only of historical interest, but this bound­
ary has been, by many authors, erroneously correlated 
with the biostratigraphic PTB at the base of the O. 
woodwardi Zone (e.g. DIENER, 1912; TOZER, 1988; 
POSENATO, 1991). However, comparison of conodont 
di stribution in the lowermost Werfen Group (KOZUR , 
1989, 1994b, 1996b, 1998a) and in the O/oceras faunas 
(MATSUDA, 198 1; KOZUR, 1989, 1994b, 1996b, 

I Fm. 
, lilT IITT II ITT II ITT II In I 

1b 

1998a; KRYSTYN & ORCHARD, 1996; KOZUR et 
aI., 1996b; WANG et aI. , 1996; YIN et aI. , 1996a) indi­
cates that the base of the O . .. voodwardi Zone is corre­
latable with the middle part of the Mazzin Member, 
considerably above the base of the Werfen Group (Fig. 
I a). 

The base of the Oloceras woodwardi Zone is the 
first biostratigraphica ll y defined PTB (GRIESBACH, 
1880) , and the finally defined PTB should be at, or 
close to this boundary. The disadvantage of this bound­
ary is that O. woodwardi GRIESBACH is only known 
from the Perigondwana margin of eastern Tethys. The 
FAD of O. woodwardi was, therefore, onl y tentatively 
correlatable with the Tethyan and the Boreal realms. 
Instead of bi ostratigraphic correlat ions, the FAD of O. 
woodwardi was equated with those different chronos­
tratigraphic levels that were in different regions used as 
the PTB , e.g. with the basc of the Werfen Formation 
(e.g. DIENER, 191 2; TOZER, 1988), wi th the base of 



138 

thc Otoceras COl/cavum Zone (c.g. TOZER, 1967) or 
with the base of the O. boreale Zonc (e.g. DAGYS, 
1994). Howcvcr, with the aid of conodonts, it can be 
shown that nonc of these boundaries corresponds to the 
FAD of O. woodwardi (KOZUR, 1989, 1994a, 1995a, 
1996b, 1997c, 1998a). 

The base of the Otoceras concavum Zone is pre­
fcrred as the base of the T riassic by most ammonoid 
workers. This is largely based on the erroneous assump­
tion that Otoceras begins in the Arctic and in Perigond­
wana at the same levcl (TOZER, 1967) and that Oto­
ceras is the first Triassic genus. In reality it is the last 
representative of the Upper Permian Otoceratacea that 
straddles the PTB. The main disadvantage of definition 
of the PTB with the base of the O. COflcavum Zone arc: 
(1 ) O. concavwn is known only from very few localities 
in remote areas of Arctic Canada and NE Siberia; (2) O. 
COllcaVllm TOZER al ways follows after a gap or at least 
after a lengthy ammonoid-free interval; (3) the direct 
fore runner of O. concavum is unknown. The latter two 
reasons prevent the base of the O. concavum Zone from 
being palaeontologically defined within a phylomor­
phogenetic lineage between two species. Thi s excludes 
the definition of the base of the Triassic with the FAD 
of O. concaVUnl. 

Moreover, conodont and sporomorph data have 
shown that the Boreal OlOceras faunas (with the excep­
tion of the uppennost O. boreale Zone s.l.) are Penn ian 
in age, if the FAD of O. woodwardi or the insignifican­
tly older FAD of H. parvus Zone are used to define the 
basc of thc Triassic (KOZUR, 1989, 1994a, 1995a, 
1996b, 1997c, 1998a; HENDERSON, 1993; HENDER­
SON & BAUD, 1996). This was subsequently con­
firmed by ammono id data by KRYSTYN & ORCH­
ARD (1996) who pointed out that O. woodwardi is 
more advanced than O. borea/e, and that the O. wood­
wardi Zone occurs in the Selong section in Tibet in a 
stratigraphic succession above a fauna with Oloceras of 
thc O. boreale group (0. latilobatum WANG & HE, 
according to KR YSTYN & ORCHARD a junior syn­
onym of O. jissiseiiatllm DIENER). This was the first 
usage of ammonoids to show the Perigondwana O. 
woodwardi Zone is younger than the Boreal Otoceras 
faunas, whereas all ammonoid workers prior to KRY­
STYN & ORCHARD (1996) had correlated the O. 
woodwardi Zone either with the O. boreale Zone (e.g., 
DAGYS, 1994) or with the O. concavum Zone (e.g., 
TOZER, 1967). Therefore, the contradiction between 
the conodont and ammonoid correlations of the Boreal 
and Peri gondwana Otoceras fauna has been resolved 
and the O. concavum Zone proven to be two ammonoid 
zones older than the O. woodwardi Zone (which is, 
according to priority the oldest Triassic ammonoid 
zone, see above). 

The FAD of Lystrosaurus is used in continental 
beds to define the base of the Triassic. In most places, 
the first occurrence of Lystrosaurus is within the lower­
most Triassic , but not necessarily at its base. The FAD 
of Lystrosaurus, however, can only be found in two 

Geologia Croatica 51/2 

areas, in South Africa and in Dalongkou (Sinkiang). In 
both areas, there is an overlap with the Upper Permian 
index genus Dicynodon. In Dalongkou, the interval 
with the co-occurrence of Lystrosaurus and Dicynodon 
contains the conchostracans Falsisca eotriassica KOZ­
UR & SEIDEL and F. postera KOZUR & SEIDEL. 
These conchostracans occur in the late Dorashamian 
(KOZUR, 1989, 1993; KOZUR & MOCK, 1993), 
whereas the lowermost T riassic (Gangetian Substage) 
contains F. verchojan;ca MOLIN. This latter species 
occurs in Sinkiang, in beds with Lystrosaurus, above 
the last occurrence of Dicynodon, and its FAD is in the 
uppermost beds with Dicynodoll. Thus, the interval 
with the co-occurrence of Lystrosaurus and Dicynodon 
belongs to the Dorashamian, perhaps with the exception 
of its uppermost part, in which F. verchojanica is 
already present. The FAD of Lystrosaurus lies therefore 
within the uppermost Permian, but beds with Lystro­
saurus that lack Dicynodon are of Triassic age. 

The FAD of the conodont Hindeodus parvus, which 
is well recognizable within a phylomorphogenetic cline 
H. Iypicalis - H. latidentatlls praeparvus - H. parVllS, 
can be traced in all marine facies and fauna l realms. It 
is common in ammonoid-free, shallow-water deposits 
of Tethys, Perigondwana, the Circum-Pacific area 
(western North America and Japan), and the Boreal 
realm. It is moderately common to rare in ammonoid­
bearing pelagic rocks in Peri gondwana and in the Arc­
tic, where the cool-water Clarkina car;l/ala group is 
better adapted to pelagic environments and mostly pre­
dominates. H. parvus is especially common in pelagic 
deposits of the basal Triassic H. parvlls Zone in western 
and central Tethys. This facies is dominated by gondo­
lellid conodonts (Cim'kina) in the Upper Permian and in 
the Lower Triassic above the H. parvus Zone. Howev­
er, after the disappearance of the Upper Permian warm­
water gondolellid fauna (c. sllbcarinata group), at or a 
little below the PTB, the western and central Tethys has 
no gondolellid conodonts in the H. parvlls Zone, no t 
even in the slope fac ies favoured by Permian and Trias­
sic gondolell id conodonts. In the Isarcicella isarcica 
Zone, gondoleliids of the cool-water C. carinata group 
invaded the pelagic environments of the central and 
western Tethys, after they had adapted to warm-water 
conditions. In the Upper Permian , the C. carinata group 
is only present in the Arctic and in Perigondwana. 

H. parvlls begins in Perigondwana a few centime­
tres below the O. woodwardi Zone in the uppennost O. 
boreale Zone, and it occurs only in the uppermost part 
of the Boreal O. boreale Zone (KOZUR, 1995a, 1996b, 
1997c; HENDERSON & BAUD, 1996). In Greenland, 
it occurs above the Otoceras-bearing beds of the O. 
boreale Zone $.S., and below the ammonoid-dated beds 
of the Ophiceras commune Zone, in beds with small 
Hypophiceras, Tompophiceras gracile (SPATH) and T. 
pascoei (SPATH) that indicate the T. pascoei Zone. 
According to DAGYS & ERMAKOV (1996) this zone 
corresponds to the uppermost O. boreale Zone s.l. It 
may be used, however, as an independent zone. 



Kozur; Problems for Evaluation of the Scenario of lhe Penn ian-Triassic Boundary ... 

HENDERSON & BAUD (1996) reported two spec i­
mens of Hindeodus c f. parvus from the O. boreale 
Zo ne s.1. of Arctic Canada, without any indication of 
the exact level within this zonc. In the lecture at the 
30th IGCP in Be ijing, they presented photos of these 
specimens that are fragmented form s that cannot be 
exac tly determined because the cusp is broken away. It 
cannot be excluded that they belong to H. pm·vIIs. Their 
occurrence was shown in the uppermost part of the O. 
boreale Zone s.1. Thi s occurrence fit s we ll with the 
FAD of H. parv/.ls in Greenland and in Perigondwana. 

In Tethys, H. parVllS was found in a ll conodont­
bearing rocks of the lowermost Triassic, e.g., in Meis­
han and other localities of South Ch ina , in Malaysia , 
Iran , Azerbaidzhan, Annenia, Turkey, Hungary, in the 
Dinarides, Southern Alps, and in western Sic ily (Italy). 
It is al so present in the Circum-Pacific area (westcrn 
North America and Japan - PAULL & PA ULL, 1994; 
IGO , 1996; KOIKE , 1996). In con trast, gondo lellid 
conodonts have a very restricted distribution in the low­
ermost Triassic H. parvus Zone. They are not only mis­
s ing in the predominant shallow-watc r depos its of 
Tethys , Perigondwana and the Circum-Pac ific area, but 
a lso in pe lagic and slope deposit s of the western and 
central Te thys. They are also absent in the most 
ammonoid -beari ng deposits of NE-Siberia. Thus , the 
FAD of H. parvus is the only palaeontological datum 
that can be found in all the marine deposits of the 
world . Using thi s datum , the marine deposits around the 
PTB can be well correlated (Figs. la & b). As the FAD 
of H. par VIIS a lmost coincides wi th the base of the O. 
woodwardi Zone, the priority PTB , most authors regard 
the FAD of H. parVlfS as the most suitab le marker for 
the base of the Triass ie (YIN, 1985, 1993; KOTLYAR 
et aI. , 1993; KOZUR , 1994a, 1995a, b, 1996a, b, c, d, 
1997a, b, e, d ; PAULL & PAULL, 1994; WANG , 
1994, 1995a, b, c, 1996; Z HU et aI. , 1994; DING e t aI., 
1995, ZHANG e t aI., 1995, 1996; IGO, 1996; KOZUR 
et aI., 1996b; LAI e t aI., 1996a; WANG e t aI. , 1996; 
WIGNALL & HALLAM, 1996; WIGNALL e t aI., 
1996; YIN e t aI. , 1996a, b; YIN & ZHANG, 1996; 
HAL LAM & WIGNALL, J997; WANG & WANG, 
1997; ZHU & LIN , 1997). 

For evaluation o f the PTB biotic crisis it is impor­
tant that the FAD of H. parvlts (base of the Triassic) is 
situated in the middle part of Boundary Bed 2 (middle 
part of Bed 27) in Meishan , within the midd le Mazz in 
Member of the Southe rn Alps, within the E2 Member 
of the Khunamuh Formation of Kashmir, wit hin the 
middle Kathwai Member of the Mianwali Formation of 
the Salt Range, in red shales immediate ly be low large 
stromatolite bod ies in Transcaucasia and NW Iran, and 
within the uppermost O. boreale Zone s. 1. (= T. pascoei 
Zone) of the Arctic. In continental beds, this boundary 
is close to the disappearance of the typical Pe rmian 
Dieyl/odoll afte r an interval of co-occ urrence of 
Lystrosaurus and DieYllodofl. The direct correlation of 
the FAD o f H. parvus in marine beds and the indirect 
co rre lations (mainly wi th conchostracans and sporo-

139 

morphs) in important continental sections is shown in 
Figs. l a & b. 

3. PROBLEMS RELATED TO THE VARIOUS 
LEVELS OF THE PTB IN DIFFERENT FACIES 

AND FAUNAL REALMS 

The exact correlation of a s uitabl e marker leve l 
close to the PTB is more impo rtant than the actual posi­
tion of the PTB for the evaluation of the PTB biotic cri ­
sis . The FAD of H. parvus is such a marke r level, 
whether this bioevent is chosen as the base of the Trias­
sic or not. As the base of the Perigondwana O. wood­
wardi Zone, the priority base of the Triassic, is only a 
fe w em higher than the FAD of H. pm'vl/s, the fina lly 
approved PTB will be, in a ll cases either very close to, 
or at the FAD of H. parVI/S, which in the followin g dis­
cussions is used as the base of the Triassic. 

The fonner diachronou s corre lations o f th e PTB 
be tween the Perigondwana margin and Tethys, within 
the Tethyan realm and above all , be tween Tethys and 
the Boreal realm , had strong ly hindered the evaluat ion 
of the biotic c ri sis. For instance , the prev ious correla­
tion o r the Triassic base at the base of the O. woodwar­
di Zone with the base o f the Werfen Group in the 
Southern Alps and with base of the O. cOl/cavum Zone 
in the Arctic, had the obvious following consequences 
for the age of the mass occurrences of fung i: in the 
pe lag ic to s lope success ion of South China, the mass 
occurrences of fungi wcre in the uppermost Pe rmian, 
the pe rcentage of fungal spores dropped be low I % at 
the base of the Boundary Beds and fungal spores are 
practically absent in the Triass ic. In the Southern Alps 
the mass occulTence of fungi would begin in the uppe r­
most Pe rmian and reaches it s peak in the lowe rmost 
Tri ass ic T esero Oolite. In the Arc tic, the mass occur­
rences o f the fungi would be totally within the T riassic. 
Taking these dis tribu tion patterns, the mass occurrence 
of fung i around the PTB would not have any spec ial 
signi ficance. 

Takin g the FAD of H. parvus as an isochronous 
marker horizon and base of the Triassic, then the g lobal 
mass occurrences of fun gi, independent from the faunal 
and flora l realm , would be be fore the FAD of H. parvlls 
with in the uppermost Pe rmi an. The mass occurrences 
decrease everywhere drastically a little before the FAD 
of H. parvus and above the FAD of H. parVlIS, fungal 
sporcs are very rare. Thus, the extinction patte rn of fun ­
gi is totally different using previously accepted diachro­
nOliS PTB corre lat ions or the isochronous marke r hori ­
zon (FA D of H. parl'lIs). Si milar modifications o f the 
detailcd cx tinc tion patte rns can be observed for other 
fossil groups. 

The fomler ass ignment of the Borcal Otoceras fau ­
nas to th e Triassic has al so caused assignment of all 
sporomorph associations with a high percentage 01" tri­
le te cavale spores (e.g., Llllldbladispora obsoleta­
LUl1atisporifes l10viaulellsis associa tion) to the Tri ass ic 



140 

despi te the fac t that these associations begin in Tethys 
in the undo ubtedly latcs t Pe rmian deposits, c.g. in the 
lower Tesero Horizon o f the Southern Alps, with upper 
Dorasham ian conodonts (see below), fusu linids, Penni­
an small fo raminifers and Perm ian brachi opods. The 
rev ision of the conodont faunas in the O{oceras beds of 
G recnl and (S WEET , 1976) by re-s tudy of SWEET's 
collection allowed the fe-evaluation of the age of the 
palynological cvents published by BALME (1979). The 
following success ion of bioevents is present: Appear­
ance of "Triass ic" sporomorph s - end of the mass 
occurrences of fungal spores - FAD of 1-1 . parvlI s. T he 
first two events arc w ith in the Dorashami an as in the 
Southern Alps, and the second event is also recogniz­
able in the uppermost Dorashamian of South China. 
Erroneous correlation of the Perigondwana and Borea l 
Oroceras faunas caused erroneous determination of the 
PTB in cont inental beds, and erroneous circular conclLl ­
s ions, e.g., the "Triass ic" age of the Boreal Otoceras 
faunas and o f the lower Tescro Horizon of the Southern 
Alps duc to the presence o f "Triass ic" sporomorphs. 

Before the rev iew of the conodont and ammonoid 
data by KRYSTYN & ORC HARD ( 1996), the erro­
neous placement of the PTB in the Arctic was difficult 
10 recognize. T here, neither at the base of the O. coJ/­
cavum Zone nor at the FAD of H. parvus nor in any 
horizon between these biostratigraphic levels, could a 
disti nct drop in diversity be observed, because a very 
low-diversity fauna was alread y present before the O. 
COf/caVUIII Zone. Th is was because a success ive de­
crease in d iversity occurred by the success ive disap­
pearance or warm-water fau nas, beginning with the dis­
appearance of fusu lin ids at the base o f the Middle Per­
mi.an (base of Guadalupian Series). This example clear­
ly ind icates that the Permian-Triassic biotic crisis was 
mainly a cris is in the warm-water biota that were 
restric ted to Tcthys at the end of the Permian. 

Scveral other problems are re lated to the exaet cor­
rela tion of the PTE. Strong facies changes from tropical 
high-dive rsit y shallow-water env ironments to low­
diversity tida l flats a rc always accompanied by a drastic 
local drop in diversity. If such changes occ ur close to , 
but no t at the PTB, such fac ies-controlled local di versi­
ty drops have generally been ass igned to the PTB biotic 
crisis. A good example is the boundary between the 
Bellerophon Limestone Format ion, with a high-diversi­
ty shal low- wate r fauna , and the lowermost Werfcn 
Group (Tcsero Oolite), wi th a low-diversity intertida l 
fauna. T his boundary is related to a sea-level drop with­
in the Dorashamian. In the eastern part of the Southern 
Alps (Carn ic Alps), thi s sea-Ievcl drop caused a sudden 
shallowing withi n the Belle rophon Limestone Forma­
tion, but the high-diversity Permian sha llow-water fau­
na continued. In the wes tern part of the Southern Alps 
(Dolomites), the same sea- level drop caused in the orig­
inall y shallower depos it s a sudden change from high­
diversit y shallow-water fauna of the Bellerophon Lime­
stone Formation to very low-d iversity fauna of in ter­
tidal ooli tic bcds (Tesero Ooli te of basa l Werfen Gro-

Geologia Croatica 51/2 

up). Despite the fact that this drastic diversity drop has 
noth ing to do with the PTB biotic crisis, but is an int ra­
Upper Perm ian facies-controlled divers ity drop, it was 
used as a c lass ical example for the severe PTB exti nc­
tion event. 

The s it uation in Meishan (South Ch ina) is different 
although a ve ry dis tinct dive rs ity drop can al so be 
observed 18 cm below the FAD of 1-1 . parvus, at the 
base of Bed 25. This d iversi ty drop is a real extinction 
event. It is dist inctl y younger than the Be lle rophon 
Limestone Formation / Werfen Group boundary. Acco­
rding to the conodont fauna and the distribu tion of the 
fungal sporcs, this ext inction level somewhat below the 
PTB corresponds to a leve l approx im ately 2 m above 
the base of the Tesero Oolite in the Tesero section and 
within the Tesero Oolite in other secti ons (c.g., Sass de 
Puti a). At this level within the Tesero Ooli te, the mass 
occurrence of fungal spores ends (as in pelagic beds at 
the top of the Changxi ng LimeslOne in Meishan a t the 
top of Bed 24), but within a shallow-water upper Dora­
shami an conodont fauna wi th Hindeodus latidentGtus 
praeparvlIs KOZUR, Isarcicella ?prisca KOZUR and 
Slepalloviles cf. dobruskinae KOZUR & PJATAKO­
VA, d istinctly before the FAD of H. Po/·VlIS within the 
Mazzin Member. No distinct change in the low-diversi­
ty fauna can be observed at this leve l in the Dolomites 
(Southern Alps) because the rich Perm ian fa una had 
already d isappeared fo r facia l rcasons at the base of thc 
Tesero Oolitc, corresponding to a level w ithin the upper 
Changxing Limestone (w ith a diverse Dorashamian 
warm-water fau na) of South China. 

Particu larly in conti nental environments, st rong 
biot ic changes at the PTB are assumed in sections with 
a long time-gap between the youngest Permian and the 
oldest Triass ic faunas. For instance, between the Tatari­
an Stage and the lowerm ost Triass ic on the Russ ian 
Pl atform , there is a long gap that comprises nearly the 
entire Upper Pcrm ian Loping ian Series (KOZUR, 1989, 
1994b, 1998a). Desp itc the Fact that thc Tatarian is 
mos tly regarded as uppermost Permi an, on the Russian 
Platfoml (Iype Tatarian) it ends in different Capitan ian 
to lowermos t Dzhulfian levels. There fore , the st rong 
fau nal changes between the continental Tatari an (Per­
mian) and Vet lugian (T riassic) that were assigned to the 
exti nction event at the end of the Permian, are in reality 
faunal d ifferences between the Middl e Permian Cap i­
tani an and different leve ls within the lowermost Trias­
s ic. Therefo re, a summa ry e ffect of la te G uadalupi an 
and PTB biot ic changes is ass igned to the PTB biot ic 
cnSlS. 

In Dalongkoll (S inki ang), where a continuous, fos­
sil-ri ch seq uence is p resent in the Upper Permian and 
Lower Triassic, the change from the Permian to Trias­
sic biOla occurs in several steps of extinction and inno­
vation that are mai nl y s itu ated wel l below the oldest 
assumed PTB, the FAD of Lystrosaurus, at which level 
no exti nction event in any fa unal or floral group can be 
observed. Even the Upper Permian vertebrate g uide 
form , Dicynodon, cont inued. A certain extinction event 



Kozu r: Problems for Evaluation of the Scen<lrio of the Penn i,m-T riassic Boundary ... 

is indicat ed by the disappearance of Dicynodon , in 
time-correlation close to the FAD of H. pan/us, but this 
extinction is only the final replacement or the Permian 
Dicynodon by LysTrosaurus that appeared considerably 
earlier. Other Permian clements, such as Permian fresh­
water gas tropods di sappeared somewhat earlier, but 
also considerably above the FAD of Lystrosaurus. 

Rather distinc t changes can be observed consi der­
ably below the FAD of Lystrosalll'lls. The conchostra­
can genus Fa/sisco that straddles the PTB , begins about 
96 m below the FAD of Lystrosaurus. The typical Per­
mian conchostraca n genera Bipemphigus, Megasifll!1l 
and Tripemphigus disappear 65 m below the FAD or 
Lystrosaurus. Arou nd th is level, a di stinct increase in 
trile te cavate spores can be observed. 

IL is velY interesting that in the continental biota the 
"Triassic" elements (taxa that straddle the PTB and rep­
resent the lowermost Triassic faunas after the extinction 
of the Permian clement s) all beg in within the Upper 
Permian , long before the extinction of the Permian ele­
ments . Thus, the conchostracan Fa/sisca appear far 
below the PAD of Lys/rosaurus, and aft er the later dis­
appearance of typica l Permian genera, a lso dist inctl y 
below the FAD o f Lystrosaurus, the generic compos i­
tion of the conehostracan faunas is a lready identical 
with that of the lowermost Triassic. Simi lar extinct ion 
and innovati on pattern s are known among the verte­
brates, where the predominantly Triassic LysTrOSal/rus 
appeared with in a Permian Dicynodoll fauna , and the 
full T riassic character of the vertebrate fauna was estab­
lished by the d isappea rance of Dicyl/odoll close to the 
PTE (if deli ned wi th the FAD of H. par.,/ls). 

Only detail ed inves ti ga tions of such a co ntinuous 
rich faunal record across the PTB as in Oalongkou can 
help to understand the extinction and recovery pattcrns 
of the continen tal faunas. Compilations of Upper Per­
mian and Lower Triassic cominel1lal faunas with poor 
stratigraphic control hi nder the eval uat ion o f the biotic 
changes in the co nt inental Upper Permi an and Lower 
Triassic faunas rather than aid the progression of these 
studies. 

4. PROBLEMS WITH THE RECOGN ITION OF 
THE EXACT EXTINCTION AND RECOVERY 

PATTERNS OF MAJOR FOSSIL GROUPS 
CLOSE TO THE PTIl 

Interpolati on 0 [" the unknown Scythian or lower­
middle Scythian diversi ty of many major foss il groups 
from the known diversity in thc Upper Permian and 
Anisian in lite rature compilat ions (e.g., ERW1N, 1993) 
is one of the major problems for the eva luation of the 
causes of the PTB biotic c ri s is. 

The reco rd of many pelag ic, and also o f shall ow­
wate r marine fauna l g roups in the lower and middl e 
Scythian is vcry poor. A large percentage of taxa tha t 
di sappeared at the PTB , re-appearcd in the uppcr Scy­
thian (upper Olenekian) or, more frequently, in the 
Middle Triass ic. For several groups the percentage or 

141 

re-appearing genera (Lazarus taxa) is 90-100 %. Never­
theless , these form s have not yet been found in the 
Scyth ian or lower-middle Scythian, not even in favo ­
urable facies. Good examples are the scol ecodonts and 
the holot hurian sclcrites. Scol ecodonts are common in 
shallow-water, gray or black limestones and shales dur­
ing the Upper Permian and Middle Triassic. During the 
Lower Triassic, these sediments are widely di stributed , 
but the examination o f more than 1000 samples in 
facies favourable for the presence and preservation of 
scolecodonts has not yie lded any specimens. All Upper 
Permi an genera , bar one, re-appear during the Ani sian 
and Ladinian. The only genus, De/osites, that does not 
re-appea r in the Midd le Triassic, is represented by its 
immedi ate successor, Pa/urites. In the broade r defini ­
tion o f Delosiles by Z/\ WIDZKA (1971) and KOZUR 
( 1973), both genera are identical. Independent of th is 
special taxonomi c question , the number of Triassic 
scolecodont Lazarus genera is 100%, none of the Upper 
Permian genera that di sappeared at or somewhat below 
the PTB , really became extinct. 

Perm ian, Middle and Upper Triassic holothur ian 
sclerit es are common bot h in s hallow-water and in 
pelagic deposits. They are especially common in Hall ­
statt Limestones , mainly reddi sh limestones with a very 
low sed im entation rate that are o ften stratig raphi cally 
cond ensed. Several hundred Scy thian sampl es in the 
11105 t favourab le facies for the occurrence and preserva­
ti on o f holothurian sclerites, among them large samples 
from Hall statl Limestones, have not y ielded any ho lo­
thurian sclerites. However, in the Middle T riass ic, 9 out 
of 10 genera, which are present in the uppermost Per­
mi an, re-appeared in the Middle Triassic . The onl y 
Upper Permian genus, which docs not re-appea r in the 
Middle Triassic, is JII I/aealldill(f MOSTLER & RAI-Il ­
MI- Y AZD. However, thi s genus does not OCCUI" in the 
upper Paratiro/ires beds and , therefore, di sa ppeared 
d istinctly be!"ore the PTS (MOSTLER & RA HIMI ­
Y AZD, 1976). Holothurian sc leriles underwen t a ra ther 
rap id evolution of the form taxa that can be well rela ted 
to natural species, and have considerable st rati g raphic 
import ance in the Midd le and Upper Triass ic (e.g., 
MOSTLER , 1969, 1973; KOZU R & MOCK , 1974). 
Despite this fact , 6 Ollt o f 8 species, which are present 
in the uppermos t Paratiroliles beds, also occ ur in the 
Middle and/or Upper T riass ic (MOSTLER & R/\ HI MI­
Y AZO, 1976). Thus, the holo thurian sclc rit es a lso 
belong to those groups, 01" which 100% of the genera 
survived the PTB bioti c c ri sis. An interpolati o n of the 
unknown Lower Triassic generic diversity of the scolc­
codonts and holothurian sclerites to be constant from 
the Upper Perm ian to the base of the lower Middle T ri­
assic would be formall y, in a g lobal aspect, co rrect. 
However, such an in terpre tation wou ld mask the true 
picture tha t these fossils we re not fou nd in the Lowe r 
Triassic even in the most favourablc facies (g ray shal­
low-water limestones for sco lcc oc!onts and redd ish 
Tiall statl Limestones for holothurian sclerilcs), despite 
inves ti ga tion of a large number or samples in different 



142 

fac ies ancl areas. They have also not been reported by 
other specialists. 

Thc fact that all Eunicida/Phy ll odoc ida genera 
(their isolated jaws are the scolecodonts) and holothuri­
an genera must have survived the PTB does not mean 
th at they were not affected by the PTB biotic cri sis. 
They were strong ly affec ted and retreated to current ly 
unknow n re l ic arcas from where they fe-sett led the 
Middle Triassic seas. T hus, even in this case, where the 
interpolations are formally correct , th ey do not show 
the real picture of the PTE faunal crisis. 

Unfor tunately, in and prior to ERWIN (I993), the 
Scythian, or at least the lower to middle Scythian d iver­
sity patterns of most of the fossi l groups were interpo­
lated from the known Upper Pennian and Middle Trias­
sic d iversity. From thi s, a totally incorrect picture of the 
extinction and recovery patterns for many major fossil 
groups emerged. On ly in HALLAM & WIGNALL 
(I997 ) a correct pic ture o f the extinction and recovery 
patte rns of some major fossi l groups has been g iven, 
but no details (amount o f the genera in the different 
Upper Permian to Middle Triassic stages) were prescn­
ted and not all the major fossil groups were considered. 
Nevertheless, the exctinction - recovery patterns pre­
sented by HALLAM & WIGNALL ( 1997) can be used 
for evaluat ion of the charac ter of the PTB biotic c risis. 
The exctinction - recovery patterns shown by ERWIN 
( 1993) are mostly literature compilations and for most 
of the major fossil groups are so mi slead ing that they 
mask rather than highlight the true extinction and reco­
very patte rns. Thi s is mainly the result of literature 
compil ati on and incorrect interpolation of the Lower 
Triassic (or lower to middle Scythian) diversity. 

Lower Scythian divers ity interpolation from known 
Upper Permian and Middle Triassic diversities pro­
duces an espec ially mi sleading picture in those fo ssil 
groups that have a high Upper Pennian and Middle Tri­
ass ic divers ity, but were strong ly affec ted at the PTB 
(real or large ly real ex tinction, none, very few or a 
moderate amount of Lazarus taxa). In these groups the 
Middl e Triass ic high divers ity is not caused by re­
appearance o f Lazarus taxa as in the scolecodonts or 
holothurian sclerites, but by a strong radiation of a very 
low-diversity fauna which survived the PTB biot ic cri­
sis , or by the new development from skeleton-free rep­
resentatives. A Scythian diversity interpolation of these 
groups shows no pronounced diversity drop at the PTB 
and a h ig h d ivers ity th roughout the Scythian that was 
not present. 

Two typical examples for a totally incorrect picture 
of the exctinc ti on - recovery patterns of major fossi l 
groups are d iscussed below. 

The Radiolar ia were shown by ER WIN ( 1993) to 
have a s li ght d ivers ity drop from 4 to 3 families from 
the Capitanian 10 the Dzhulfian, and this level remains 
constan t unt il the Anisian (Fig. 2). Th is d iversity pat­
tcrn is not only totally outdated, but it is interpolated [or 
the Lower Triassic interval, because until recently no 
radio larians were known from the Brahmanian and low-

Geologia Croatica 51/2 

er Olenekian. On ly KOZUR et al. (1996a) described the 
first known radio larians from this interval. Two spec ies 
of two genera and two fam ilies we re discovered. As 
these are Palaeozoic types, they probably have survived 
the PTB , but only in the upper Olenekian does the 
diversity o f the radiolarians again become higher. Most 
o f the upper Olenekian form s may have evo lved from 
ske leton-free or simple spicu lar radio larians. T he real 
diversity pallern of the rad iolarians is shown in Fig. 2. 
There is a strong drop in diversity immed iate ly below 
the PTB , an extremely low-diversity fauna in the lower 
and middle Scythian (Brahmanian = "Induan", and in 
the lower O lenekian), a recovery to near Upper Permian 
d iversity in the upper Olenekian and lower Anisian, and 
an explosive radiat ion in the middle and upper Anisian 
with a diversity far higher than that of the Upper Permi ­
an. The picture would be more impressive at genus and 
species level, but for a comparison to hi ghlight the 
immense problems that were caused by interpolation of 
the Scythian diversity, the family level has to be used, 
as ERWIN ( 1993) used thi s taxonomic level. Whereas 
during the lowe r and middle Scythian the number o f' 
species, genera and fam ilies is the same (2), the number 
of the Dorashamian genera is about 2 times , the number 
of the upper Olenekian genera about 1.4 times, and the 
number o f the upper Anis ian genera about 2.5 times 
larger than the number of fami lies. Dorashamian genera 
have on average 2-3 species, upper O lenekian genera 
1- 2 spec ies and upper Anisian 2 spec ies. As I have 
investigated these rad iolarians by myself, the degree of 
splitting for the compared radiolarian faunas is the 
same. 

The in terpolated pic tu re presented by ERWIN 
( \993) indicates that nothing happened with the silice­
ous plankton at the PTB. In reality, the skeleton-bearing 
radiolarians nearly di ed o ut , and the production o f 
organic silica dropped close to zero. Even in the Pan­
thalassa Ocean the lower and middle Scyth ian has no 
radiolari tes, onl y shales that interrupt cont inuous Per­
mian to Jurassic radiolarite sequences. In this example 
the interpolation of the diversi ty in the Scythi an pre­
sents a totally incorrect picture. 

A simi lar inco rrect pict ure was presented by ER­
WIN (1993) for the non-fusulinid foram ini fers (Fig. 2). 
Also for thi s group, a constantly high divers ity was sho­
wn (l9 families) from the Dorashamian to the Anisian. 
In reality, only the Upper Permian and An isian forami ­
ni fe ral faunas show th is high dive rsity, whereas the 
Brahmani an and lower Olenekian foram iniferal faunas 
have a very low diversity . Even considering the fa ct 
that the Anis ian foraminiferal famili es have a high per­
centage of Lazarus taxa, there is a very distinct diversi­
ty drop at the PTB. 

A simila rl y incorrect, and for the Lower Triassic 
interpolated scenario, was shown by ERWIN ( \ 993) fo r 
the sili ceous sponges (Fig . 3). In thi s case, the recon­
st ruction a t family leve l is very diffi cult because the 
siliceous sponges are mostly not class ified at family 
level, but in species, genus and order levels. Moreover, 



Kozur: Problems for Evaluation of the Scenario of the Pennian-Tria~s ie Boundary ... 

30 

25-

20 

15-

10 

5-

y 
! 
! 
J 
! 
i 
i 
! 

••••••• J' -=., .................. . 

! 
! 

.. _.-.. -.-.. _ .. -: .j 
t ./ 
, ! 
t j 
! . 

! 
! 
! 

'.. ! ),.--4/ 
.- ----1- -- -7"···" 

I .... --4 

OJ---r--',--~--"---~,-,, 

c a 
'c 

:R 
8 

C c.-. c c 
o .Q~c 0 0 ·E Co 32 .Uj 

!2 ~-a :g ~ 
-t; ..c C Q) 

!2 0;- 0 o as ~ 
o 

Radiolaria 
Diversity lafter Erwin) ---.--. 
Uninterpolated 
d iversity _ ....... _ ... 
Non Fusulinid Foraminifera 
Diversity (after Erwin) ........... 
Uninterpolated 
diversity 

9 

143 

Fig. 2 Stage-level Capi tania n-
An isian fam ily di versit y pat­
te rn s o f Radi o laria and non­
fusuiinid fonlm inifera after 
ERWIN ( 1993) in comparison 
with not interpolat ed d iversity 
patterns. The Scy thian radio la­
rian famil y di ve rsity patterns 
by ERWI N ( 1993) is clearly 
int erpo lat ed . and shows no 
impact of the PTB biotic cr isis 
on th e dive rsit y o f Radio lari a 
in fami ly leve l. The not inter­
polated family diversity pattern 
o f Radiolaria shows a nearl y 
compl ete ex ti nction at the PTB, 
II beg in ning reco very in the 
upper Olenekian and a st rong 
rad iati on in the An isian. The 
di versity pallern of the non -fus­
ul inid foram inifers by ERWIN 
( 1993) fo r the Scyth ian part is 
al so interpolated from the kno­
wn DOrdsha mi an a nd An isian 
hig h di ve rsity faunas becau se 
the di s ti nc t lower and midd le 
Scy thian min imum is mi ss ing. 
In the lin interpolated div ersity 
eurve fo r fo ram inifers. the 
Dzhulrian and Dorashami an fa ­
m il y di versit y was ove rtaken 
from ER W IN ( 1993). because 
it li es within the error range 
caused by d ifferent taxonomic 
scope of the families. The Ani­
si an diversity at family level 
li es below th e Upper Permian 
d iversi ty. Lazarus taxa are do­
minant in famil y level. The 
diversity inc rease in fami ly lev­

el from the upper Olenekian to Anisian is low. but in genus and species level it is high. The strong incre.lse in fami ly level d iversit y from Ihe 
lower to upper Olenck ian can be only observed in eastern Tethys and open-sea pelagic deposi ts in western TClhys (C. g .• wcstern Sicily). In 
upper Olenekian shallow-water deposits of western Tethys foramin ife rs are common but have a low di versi lY. 

most of the taxa in the Dorashamian and Anisian have 
to be reconstructed from sponge spicules. 

Thc Demospongiae (Fig. 3) were shown by ERWIN 
( 1993) to have a very sl ight divers ity drop from the 
Capitan ian to the Dzhulfian (from 15 to 14 famili es), 
thcn a constant family diversity (14 famili es) until the 
uppermost Permian , and an increase to 15 fa milies in 
Ihe " Induan", a diversit y that remained constant until 
the end of the An isian. In reali ty , the Demospongiae 
have a strong d iversity drop from the Capitan ian to the 
Dzhu lfian (from 12 to 6 families) and thi s di versity 
remains constant unt il the top of the Dorashamian. 
They disappeared at the PTB and are not known from 
the Scythi an. They re-appeared in the Middle Triassic, 
where their diversity quickly became higher than in the 
Upper Permian. There are many Lazarus taxa, but sev­
eral groups became ext inct at the PTB. 

The Hexactin elli c1a (Fig. 3) are shown by ER WI N 
(1993) to havc a drop in family diversity (6 down to 4 
famili es) from the Capitanian to the Dzhulfian, and this 
diversity remai ned constant until the end of the Anisian. 

Also this diversity pattern is interpolatcd for thc Scyth i­
an because in 1993 only one Hexaclinellida family (one 
genus, one speeics - RIGBY & GOSNEY, 1983) was 
known from the upper Scythi an, and on ly KOZUR et 
a!. ( 1996a) reported the fi rst siliceous sponge spicules 
from the upper Brahmanian and lower Olenekian, 
which also belong to a single species, perhaps the same 
species as in the upper Olenekian. 

The real di stribu tion pattern of the Hexaeti nellida 
(based mainly on data of Pro f. H. MOSTLER, Inns­
bruck, pers . comm.) looks tota ll y d ifferent (Fig. 3). 
There was a drop in diversity from the Capitanian to the 
Dzhulfian from 6 to 3 fam ilies tha t continued until the 
end of the Dorashamian (2 fam ilies). There is a very 
distinct drop in species diversity from the Capitanian to 
the end of the Dorashamian (about 70% drop in diversi~ 
ty), nevertheless, Hexactincllida arc still common in the 
uppermost Dorashami an (e.g., in western Sic il y -
KOZUR & MOSTLER , in prep.). In thc uppcr " lndu­
an" and Olenekian , one genus with one spec ies is pre­
sent. In the Anisian, the diversity of the Hexactinellida 



144 Geologia Croal ica 51n 

20 

15 .................................................... 

Porifera 

Hexoctinellida 
Diversity (after Erwin) 
........ ---
Uninterpolated 
diversity 

10 

Demospongiae 
Diversity (after Erwin) 

Fig. 3 Stage-level Capitan ian to Anisian family di versi­
ty patterns of siliceous sponges (Demospongiae and 
Hexactinell ida) . Com pari son of the di vers ity pat ­
tern s wi th interpo lated Scythian dive rsi ty by 
ERWtN ( \993) that show no PTB ex tinction event, 
with the not intcrpolat cd divers ity pattern that 
shows the known Scythian diversity. Inte rrupti on 
of the curve means that in the Scythian no Demo­
spongiae and in the lower Brahmanian (lower Indu­
an) no Hexactincllida arc known. This curve shows 
that the si li ceous sponges have been st rong ly 
affected by the PTB biotic cr isis and recovered 
onl y in the Middle Triassic, wherc many Lazarus 
taxa appeared. 

" 5 .......•....... 

Uninterpolated 
d iversity _._.-

0 
c c c c c c 
0 0 .Q 0- 0 0 .- c 'c :g E c 0 :s2 'Vi 

.2 o ::J Q) ~ '" 0 ED c 
'0. N '" Q) 

0 '" c 0 '" 0= 0 Q () 

8 iO 

started with low diversity pioneer faunas, and the diver­
s ity rapidly increased within the Anisian ( 15 families). 
There are many Lazarus taxa of groups 1hal disappeared 
a t the end of the Permian or earli e r, but because the 
diversi ty is mostly reconstructed from sponge spicules, 
it cannot be excluded that some forms arc 1101 Lazarus 
taxa, but homeomorphic forms that newly developed in 
the Middle Triassic. 

In all these cases the diversity drop is far hi gher 
than indicatcd by ERWI N (1993). Howcvcr, cxcept for 
the radiola rians, the number of the Laza ru s taxa is 
rather high, for inslallee, in the siliccous sponges more 
than 50%. The impo rtan t question is, wh y do they re­
appear only in the uppe r Ol enekian , or mostly on ly in 
the Middle Triass ic. 

The above exampl es have shown that interpolation 
o f the Scythian dive rs ity from the Upper Pe rmian and 
Middle Triass ic diversities leads to completely incor­
rect divers ity patte rns across the PTB and in the Scyth i­
an. The true di versity pat te rns from the Upper Perm ian 
to the Middle Tri assic show a lot of de tail s of the 
ex tinc tion and recove ry processes in diffe rent fossil 
groups. But even true numeric diversity patte rn s are 
mos tly insuffi c ient to show the real ex tinc tion and 
recove ry patterns. As most fossil groups comprise a 
wide variety of taxa adapted to totall y diffe rent fac ies, 
it is important to s tud y what were the extinction and 
recovery patterns of different taxa within an investiga­
ted fossil group. Forms that li ved in diffe rent environ ­
ments must be separate ly investigated, warm-water ver­
Sll S co ld -water taxa, shallow- water versus deep-water 
taxa, fresh-water versus marine taxa, terrestri al ve rsus 
aq uatic taxa, light-dependent taxa versus light-indepen-

dent taxa, taxa that need hi gh oxygen content in the 
water versus taxa that could live under reduced oxygen 
content, taxa that lived in the northern hemisphere ver­
sus taxa that lived in the southe rn hemisphere etc. 

For instance, only warm-wale I' faunas were s trongly 
affected by the PTB biot ic c ri sis . In the low-diversity 
Boreal faunas no di stin ct ex tinction event can be 
observed, neither at the base o f the O. COl1caVUnI Zone 
nor at the much highe r l:;"AD of 1-1. pm'Vlts or at any lev­
e l in be tween. An exception is the disappearance of 
sponge spicules a lilli e below the FAD of 1-1. p arlil/s. 

The Boreal land floras and the fun gi were, however, 
rathe r st rongly affected , e.g., the end of the fun gal mass 
occurrences somewhat below the FAD of I-I. parlilfs. 

Deep-water, cold bOltom water, benthi c faun as 
(palaeopsychrospheric fau nas), investigated mainly 
among the ostracods (KOZ UR, 1991 ), arc not g reatly 
affected , but the upper Scythi an and Middle Triass ic 
palaeopsychrospheric faunas consis t main ly of Lazarus 
taxa. Howeve r, these may not be true Lazaru s taxa 
because no lower and middle Scyt hian paJaeopsychro­
spheric os tracod faunas are currently known. 

Li g ht -dependent taxa (coral s, green al gae) were 
strongly affected, but as they are also warm-water taxa, 
it is difficult to dccide which factor (light or tempera­
ture changes or both) was dec is ive for the st rong extinc­
tion event among these faunas and no ras. 

Fresh-water faunas with rreeze - and/or drought ­
res istant eggs were nol affec ted by the PTB bioti c crisis 
(e.g., Falsisca and Euesrheria among the conehos tra­
cans, both present in tcmporary fresh-water lakes of the 
tropical and Boreal real ms). Also other fresh-wat er fau ­
nal elements that occur in the Pemlian both in the Bore-



K07.ur: Problems for Evaluation of the Scenario of the Pcnnian-Triassic Bound;lry ... 

a l and tropica l realms, were not affected by the PTB 
(Danvil1ula among the ostracods). 

Different aspects of the investigat ion of the ex tinc­
tion-recovery patterns can be well studied in the ostra­
cods because this group has common representat ives in 
fresh-water and marine, shallow-water and deep-water 
deposits , warm-water and co ld-water biotopes, and 
among the ostracods there occur taxa that could li ve 
only under normal oxygen content and others that could 
live under reduced oxygcn contents in the sea water. 

If we compare Upper Permian with Lower to Mid­
dle T riassic ostracods as a who le, we cannot find many 
dilTe re nces. The Upper Permian ostracod faunas are 
dominated by smooth Bairdiacea, such as Bairdia , Cry­
ptobairdia, Bardiacypris, Fabalicypris, and in palaeo­
psyehrospheric deep-water ostracod faunas also Aca­
thoseapha. The same genera are predominant in the 
Upper Scythian and Middle Triassic ost racod faunas. 
Sculptured Ba irdiacea are common in the Middle and 
Upper Triassic, but some are also present during the 
Upper Permian. This minor difference in the bairdi a­
cean fauna is an evolutional)' change. 

Cavellinids (Cavel/ ina , Sulcel/o) are very common 
both in Upper Permian and in Triassic ostracod faunas. 
During the Middle Triassic transitional forms 10 Cythe­
reI/a occu r, but this difference is also a normal evo lu­
ti onary change. 

Kymatophobe ostracod faunas (ostracods that avoid 
environments with turbulent water movement s), are 
both in the Upper Permian and in the Middle and Upper 
Triassic rich in Healdiacea. 

The Permian and Lower-Middle Triassic Cyprido­
copina and closely related form s are s imil ar. Aeratia, 
Aeratino and Microcheilinella are common both in the 
Upper Pennian and in the Middle-Upper Triassic. How­
ever, whereas they occur in both deep-water and shal ­
low-water deposits dur ing the Late Permian , they are 
restricted to deep-water deposits during the Triassic. 
Triassocypris is present both in the Upper Permian and 
in the Triassic. BashkirinG and Haworfhino have close­
ly related successors in the Lower and Middle Triassic. 
The only di stinct difference is the disappearance of 
Praepifatina that is common lip to the top of the Penn­
ian. 

Cytherocopina are dominated during the Upper Per­
mian by Bythoey lheraeea and in the palaeopsyehros­
pheric deep-water faunas also by Tricorninacea. Most 
or the Upper Pemlian (and older) Bythoeytheraeea gen­
era are al so present in the Triassic, such as .Iollesia, 
Keijicylhere, Nemoceralina, Poraberounella and Trias­
sacytlle,.e. Other Upper Permian Cytheroeopina belong 
to the Youngiellidae, Cytherissinellinae and ludahelli­
nae. The Youngiellidae end at the Pff boundary. In 
cont rast, most of the Cytherissinellinae and ludahe lli ­
nac genera a lso occur in the Triassic, such as Calfi ­
cythere, .Iudahella and Gruelldelicythere with the sub­
genus Trodoeylhere. Only Visnyoefla is restricted to the 
Pennian. Conseq ucnt ly, the Scythian Cylherocopina 
cons ists nearly of the same genera as the Upper Permi -

145 

an ones. Beginning in the upper Scythian and above all 
in thc Middle and Upper Triass ic, numerous new Cyt­
herocopina genera evolved , but this is a normal evolu­
tionary process. 

Except for the above mentioned ostracods, Hollinel­
laeea of Paleocopida, Kloedenell aeea of Platyeopida 
and Kirkbyacea of Reticulocopida arc common in 
Upper Pennian shallow-water deposits. The commonly 
expressed view that the Palaeozoic and Triass ic ostra­
cods are very different because Paleocopida are present 
to the top of the Permian but absent in the Triassic, is 
not true. Firstly, the Paleocopida in the Upper Permian 
shallow-water deposits are onl y represcnted by the 
genus /-/ollinella and secondly, this genus is dom inant 
in lower Scyth ian shallow-water deposits. 

Kloedenellacea are vel)' common in the Upper Per­
mian, but malnly represented by 3 genera of Perprim ili­
idae: /-Iullgarogeisino, Ila logeisina and Indivisia . The 
last two genera are also present in the Lower Triassic. 
Other Kloedenellacea, like Pselldobeyrichiopsis, are 
very rare even in the ex tremely rich Upper Pe rmian 
ostracod faunas of Hungary. 

The Upper Permian Kirkbyacea are common and 
diverse in shallow-water environments. Several genera, 
especially Carinaknighfina, continued in the Early Tri­
assic of Peri gondwana and of eastern Tethys. Within 
the Triassic, they have becn replaced by lypical Punci­
acea that evolved from small Kirkbyacea, but this tran­
sition had already begun wi th in the Late Carboniferous­
Latc Permian time interva l, where such characteristic 
punci id features evolved, such as the bracket teeth. and 
nearly all Kirkbyacea acquired a calcified inner lamella 
during the Late Permian. 

No distinct changes can be observed within the 
Cladocopida and Myodocopida. Polycope is common in 
the Upper Permian and in the Triassic. On ly some, 
rather rare specialized form s, such as Nodopolycope, 
are restricted to the Upper Perm ian. 

Even such ostracods that are very rare or not yet 
known in the Permian survived the P(f boundary. The 
myodocopid Cypridinidae that are very rare in the Per­
mian became a little more frequent in the Triass ic, but 
no distinct differences betwecn thc Permian and Trias­
sic form s can be observed. True and defi nitely not 
reworked "entomozoids" occur in the Triassic (KOZ­
UR, in prep.). 

Paraparchitacea and Binodicop ina di sappea red at 
the Permian-Triassic boundary, but the Upper Permian 
Binodicopina are only represented by the rare Neoul­
richia . 

The Dorashami ~lI1 and Lower Triass ic fresh water 
ostracod faunas consist of Danvinula. 

As a whole, the faunal changes between the Upper 
Permian and Triassic ost racod faunas are insignificant. 
Most of the Permian ostracod families and genera sur­
vived into the Triassic. However, as shown below, this 
picture is oversimplified. 

The Upper Permian Tethyan shallow , warm-water 
ostracod faunas are very dive rse and cons ist both of 



146 

" modern forms", like Bairdiacea including sculptured 
Bairdiacea, Cylherocopina, Cypridocopina, and " Pala­
eozo ic form s", like paJeocopids, kirkbyaceans, kloe­
dene llids, and cavellinids. In the Middle-Upper Triassic 
shallow-water ostracod faunas, the "Palaeozoic" forms 
arc no longer present except for com mon transitional 
forms from cave llinids to cythe rell ids and very rare 
Punc iacca that evo lved from Kirkbyacea (KOZUR, 
1998b). However, th is does not mean that the extinc tion 
of the Pa laeozoic forms occurred at the P(f boundary. 
On the contrary, in the Tethyan lower Scythian ostracod 
fauna s the " modern [ofms" a rc missing. These faunas 
consist mainly of Hollillella tillRi (PATTE), somctimes 
accompanied by a Caveltilla or the cavcllinid Lallgdaia 
species and lor an If/divisia species of Kloedenellacea. 
Thus, it appea rs that the m ixed Palaeozoic-Mesozoic 
Tethyan Upper Pe rm ian sha llow, warm-water fauna is 
fo llowed by a 100 % Palaeozoic fauna. These forms, the 
cavelli nids, the klocdene llids, but a lso the pa leocopids 
a re filte r feeders (ADAMCZAK, 1969), ab le to live 
und e r dysaerobic conditions as has been shown for 
Meso-Cenozoic fi lter feeder faunas (BOOMER & 
WHATLEY, 1992; LETl-IIERS & W HATLEY, 1994, 
1995; WHATLEY, 1995). 

Th us, if we do not compare the Upper Permian and 
the Triassic faunas as a whole, but examine in de tail 
what happened at the P / T boundary, then we can sta te 
that in the lowermost Triassic dysaerobic conditio ns 
a lso prevai led in shallow-water deposits, as in the Wer­
fen fac ies. The re was a kind of superanoxia (ISOZAKI, 
1994, 1997), because at this time there were widesprcad 
anoxic conditions in ocean ic deposi ts tha t rcached to 
unusually shallow levels. These superanoxia were also 
de tcJl11ined by evaluation of sedimentological or micro­
fac ial and geoche mi cal criteria (HALLAM , 1994; 
HA LLAM & W IGNALL, 1997; LAI e t a I. , 1996b; 
WIGNALL & HALLAM , 1992, 1993; WIGNALL e t 
aI., 1995, 1996, 1998). They lasted for an unusually 
long time, in many places throughout the entire Lower 
and Midd le Scythian (Brahmani an = " Induan" and low­
er Olenekian), in other places only for one or two cono­
dont zones (J-/. parvus or/and I. isarcica zoncs), as in 
the deep-water deposits in Sicily. 

In the upper Scythian and Middle Triassic, the typi­
cal Palaeozoic, low-diversity fauna recovered first , with 
the re -a ppea rance of Ilumerous Lazarus taxa in the 
upper Scythian. Nearl y all taxa that disappeared at the 
PTB, re-appeared in this levcl (scc above). At the same 
time, the J-Iollinacea and Kloedenellacea became extinct 
in s hallow mari ne fauna s. Only a few Kloedenellacea 
survived in upper Scyth ian brackish environments, but 
became extinct in thi s fac ies at the end of the Scyth ian. 

This ex tinction-recovery pattern can be found in all 
shal low marine, warm-water fauna s of Te thys, from 
westernmost Tethys (KOZUR, 1985) to easte rnm os t 
Tet hys (c.g., WANG & WANG, 1997). However, the 
Borea l and Pcrigondwana ostracod fauna s show a dif­
ferent ex tinction pattern at the PTB. In the Boreal realm 
bo th the Upper Permian and Lower Triassic ostracod 

Geologia Croatica 51/2 

fa unas have a very low divers it y, and no obviou s 
changes occur a t the PTB , wherever it is placed. In 
Pcrigondwana, there is also no d istinct extinction event 
in the os tracod faunas at the PTB. Both in the upper­
most Permian and in the Lower T riass ic a moderate ly 
diverse temperate-water ostracod fauna is present. It 
contains common, but low-divers ity Kirkbyacea (main­
ly Carinaknighfina and other sma ll form s, bu t mainly 
with othe r spec ies as in Tethys), ve ry low-di vers ity 
Bairdiacea without the tropica l scu lptured Ba irdiacea, 
ve ry low-d ive rsity Cypridocopin a (Microche itill ella), 
low divcrs ity Cythe rocopin a, and a few Cavell inidae 
(SOHN, 1970). The Hollinella-eave llini d-k loedene llid 
boom of the lowermost T riassic of Tethys is miss ing. If 
we look the furthe r differences to the tropical T e thys 
both in the uppemlOst Perm ian and in the Lower Trias­
sic, then we can state that the uppermost Permian fauna 
is a cool-temperate fau na o f moderate diversit y, in 
which all the tropical forms, such as sculptured Bair­
d iacea, strongly sculptured representati ves o f Kirkby­
acea and Kloedene ll acea a re missing. Moreover, the 
s trong anoxic event in the I-I. par VIIS and t. i.wrcica 
zoncs is missing. Instead, the anoxia began immed iately 
above the I. ism'ciea Zone (WIGNALL e t aI., 1996). 
The differences in th e faunas be tween Peri gondwana 
and the Tethys (cool-temperate versus tropica l) and the 
dist inctly latc r beg inning of the s trong anox ia in Peri­
go ndwana compared with the tropical T et hys a ll ow 
testing of whether the anoxia were e ither d ircctly 
respons ib le fo r the PTB ex tinct ion (HALLAM , 1994; 
HALLAM & WIGNALL, 1997; WIGNALL & HAL­
LAM , 1992, 1993; WIGNALL ct a l. , 1995, 1996, 1998) 
or only indirectly (by preventing the rapid recovery of 
the Tet hyan warm -watcr fauna), and the assumed vol­
canic winte r had the main ki lli ng effect on the Tethyan 
warm-watcr faunas (KOZUR, 1994a, I 996b, c, d , 
1997b, c). 

T he moderate diverse Peri gondwana cool-tcmperatc 
ostracod fauna straddles the PTB wit hout distinct 
changes. Thi s could be due to the fac t that the non-trop­
ical ostracod fauna was unharmed by thc short-last ing 
volcanic win ter (the expected response of a cool-tem­
perate fauna to a three - six month pe ri od of coo ling). 
An other explanation may be the absencc of anoxia in 
the Peri gondwana H. parvlIS and t. isarc ica zones. 
I Iowcver, th is ostracod fauna also straddles the onset of 
thc anoxia above the f. isarcica Zonc. For example, the 
same Kirkbyacea as in the uppermost Permian are com­
mon in the lower Mittiwali Membe r of the Mianwal i 
Format ion (SOHN, 1970), whereas the change to dys­
acrobic cond itions had a lrcady occurred wit hin thc 
upper part of the underlying Kathwai Member (W IG ­
NALL et al., 1996). There is some ext inction connected 
wi th the begi nning of the anoxia (ma in ext inct ion hori ­
zon in WIGNALL et aI., 1996), but the divers ity drop 
in the macrofauna at thc tran siti on from highly oxy­
genated sha llow-watcr to more basinal, poor oxygena­
tcd dcposits is a normal rcaction to such a facies change 
independent of the strat igraph ic level in which thi s 



Kozur: Problems for Evatu:lIion of the Scenario of the Pcnnian~Trias.~ ic Boundary ... 

faci es change occurred, and unrelated to a mass ex tinc­
tion even t. This is best proven by the fac t that the same 
react ion to this facies change is found in Perigondwana 
at diffcrent levels (W IGNALL et aI. , 1996). It occu rs 
sooner, where the anoxia began earlier (Kashmir) and 
later, where the anoxia began later (Sail Range). This 
may produce a local or regional, but not a global low­
divers ity fauna and flora , and no world-wide mass 
extinction. Therefore, even the sllpe ranoxia does not 
have a global killing cffeet on the tropical warm-water 
fauna, and it cannot affect the fauna and flora of the 
upper 10-20 m of the water column of the entire tropi­
cal Tethyan realm. However, this fauna and flora (green 
algae, reef community and other warm-water, shallow­
wate r faunas) were the most strongly affected by the 
PTB biotic crisis. 

The third type of change in the ostracod faunas was 
discovercd by HAO ( 1992) in Guizhou, in the central 
part of eastern Tethys. As in the entire Tethyan realm , 
the Upper Permian ostracod faun a is a highly diverse 
fauna, consisting of " modern" and Palaeozoic types 
(see above). The southern part of the inner eastern 
Tethys should be thc least influenced by a killing effect 
of the volcan ic winter because it was further away from 
the huge volcanic emption center close to the northeast­
ern end of eastern Tethys (at the transition to Panthalas­
sa), and it was close to the tropical Panthalassa, where 
obviously most of thc Lazarus taxa of the Uppcr Pemli­
an shallow, warm-water fauna survi ved the PTB biotic 
crisis. As expected, this is the case despite the fact that 
the anoxic event in the H. pm·vlls Zone is very pro­
nounced. The latter is indicated by the booming of 
Hollillella and Langdaia. However, in the Guizhou fau­
na some of those ostracods are also present which dis­
appear in most Tethyan warm-water faunas at the PTB, 
including ACI·aria, Faba/icypris, "Paraeypris" and 8a­
shkirillo (t he first three forms re-appear in the Upper 
Scyt hian or Middle Triassic, whereas instead of Bashki­
rilla the closely related successor Spinocypris appears 
in thc lIpper Scythian). Also the kirkbyid Carinaknig/rl­
ina is common in the H. parvus Zone. The inner eastern 
Tethyan area was therefore either close to or a part of 
the refuge for the Upper Permian shallow, warm-water 
benth ic ostracods. 

The ex tinction - recovery patterns of the ostracods 
yield many important data, including: the presence of 
pronounced anoxia in the Tethyan lower Scythian 
which reached to an unusually high level in the water 
col umn ; the clear evidence that the killing effect at the 
PTB was caused by a temperature drop and not by the 
beginning of the anoxia; and sugges tions, that the refu­
ge of the numerous Lazarus taxa that re-appeared in the 
upper Scythian and Middle Triassic may have been sit­
uated in shallow-water areas in the tropical part of large 
oceans, such as Panthalassa and perhaps also in the 
southern part of eastern Tethys. To obtain these results 
however, it was necessary not to make any interpola­
tions of the Scythian diversity, and in contras t, the 
divers ity - recovery patterns in different areas, and 

\47 

above all climatic zones, must be regarded separately. 
Another, not so serious problem for most groups, is 

the c laborat ion of thc diversit y patterns at a too high 
taxonomic category. Often the diversity pattenlS of dif­
ferent groups are show n for the family leve l (e.g ., 
ERWIN, 1993) because most authors work exclusively 
with data compiled from the literature and not with 
their own results from the study of a major fossil group. 
For many groups, the diversi ty patterns at famil y level 
show a fai rly good picture of the extinct ion and recov­
ery patterns around the PTB, but generally at genus lev­
el the result s are more reliable. However, there are 
some groups, e .g., the conodont s, for which only the 
species level shows the impact of the PTB biotic crisis. 

The conodonts show no diversity drop at genus lev­
el around the PTB. This lead to thc rcpcatedly exp­
ressed assumption "that conodonts were almost unaf­
fec ted by the P-T exti nction" (HOFFMANN ct aI., 
1998). This, howevcr, is not correct. At species level, 
there is a distinct low diversity interval in the latest Per­
mian and in the lower fi ve Triassic conodont zones with 
two minima in the H. parvlls Zone and in the S. kum­
meli and lower N. di ener; Zones. However. even the 
study of the conodont diversity at species level around 
the PTB gives an incorrect picture because among the 
conodonts the warm-water species (in the Dorashamian 
restricted to the tropical Tethyan area) and cool-water 
species (in the Boreal realm and at the Peri gondwana 
shelf as well as in cold bottom-water in the Tethys) 
were affccted in different manner by the PTB biotic cri­
sis. Whereas the warm-water restricted Clarkina sub­
carinara group disappeared at the end of the Permian , 
the cold-water adaptcd Hindeodlls Iypicalis and Clarki­
na caril/ara lineages nourished , with distinct diversifi­
cation and occupation of the Tethyan biotopes after the 
di sappearance of the warm-water forms. Therefore, a 
total turnove r of the conodont faun as occurred at the 
end of the Permian , but because the diversification of 
the cool-water elements (s tarted at the base of the I. 
isO/dea Zone) occurred only a little after the extinction 
of the warm-water form s (mainly at thc base and part ly 
at the top of the las t Permian conodont Zone, thc C. 
meishal1ellsis - I-I . la tidelltaflls praeparvf{s Zone), the 
di vers ity drop in species level was not very significant. 

At the top of thc Gangetian Substage (top of the H. 
postparvus - H. sosioensis Zone;::; top of the C. carina!a 
interv al Zone), all hindeodid conodonts disappcarcd 
and the C. carinala group became very rare_ At this 
second pronounced ex tinction event in the conodont 
fauna , on ly the cool-water conodonts that survi ved the 
mass ex tinction in the uppermost Pe rmi an and flour­
ished in the lower three Triassic conodont zones were 
affected. Somewhat later a strong diversification of 
Tethyan warm-water conodonts began that also invaded 
the Boreal rcalm. The disappearancc of the hindeodid 
conodonts especially indicates an important change in 
the conodont fauna , as this group had , in the lowermost 
Triassic, its strongest diversification and widest regio­
nal and facial distribution of its Late Palaeozoic to ear-



148 

lies t Triassic history . With the disappearance of this 
group, the mixed Palaeozoic-Triassic conodont fauna of 
the earliest Triassic was replaced by a low-diversity 
Triassic conodont fauna. 

Thus, detailed conodont studies show that the con­
odonts were strong ly affected by the PTB biotic crisis. 
At first the Late Penniao wann-water conodonts totally 
disappeared in the lates t Permian, and three conodont 
zones later the cool-water conodonts disappeared 
almost totally. This extinction pattern yie lds important 
data for the causes of the PTB biotic crisis : A drastic 
drop in the temperature in low latitudes during the 
uppermost Pennian that coincided with a huge volcanic 
fallout in eastern Tethys (4- 6 cm dust tuff over an area 
of 2 million km' ) and a strong global warming three 
conodont zones later. 

S. SOME REMARKS ON THE ABIOTIC 
INDICATORS OF THE PTB BIOTIC CRISIS 

There are no indications of an impact of a large 
extraterrestrial body (no iridium peak) close to the PTB 
(Y IN & ZHANG, 1996). However, a lillIe below the 
PTB an enrichment of microspherules can be fou nd 
(Japan, China , Hungary). In Mei shan , South China, 
they occur in Boundary Beds I, at the level of a sharp 
drop in fau nal diversity. According to YIN & ZHANG 
( 1996), they are e ither of extraterrestrial or of volcanic 
orig in , and the si liceous microspherules are s imilar to 
Ihose found in the plume of the Ml. Etna volcano. As 
these microspherules occur both in an al tered volcanic 
du st layer (Bed 25) and in an overlying anoxic layer 
(Bed 26), they may be of both volcanic and extraterres­
trial origin. In the BUkk Mts . of Hungary , a few cen­
timetre thick microspheruie layer occurs about one 
metre above the top of the Nagyv isny6 Formation 
(equivalent of the Bellerophon Limestone Formation of 
Ihe Southern Alps), in the basal Werfen Group with a 
low diversity lates t Pennian fauna, a few meters below 
Ihe FAD of H. parvLls. The big faunal drop occurs at the 
top of the Nagyvi sny6 Formation , but may be facies­
coni rolled. According to DETRE et al. ( 1998), the 
microspherules of this horizon are of ex trate rrestrial 
origi n. This horizon may be contemporaneous wi th the 
Boundary Bed I , because the sedimentat ion rate in the 
BUkk Mts. was high, whereas the Boundary Beds of 
Mei shan are strongly condensed. Both horizons are 
above the LAD of fu sulinids and a diverse Permian fau ­
na and below th e FAD of H. parvlI s. Accordi ng to 
DETRE et al. ( 1998), these interstellar microspherules 
arc related to a supernova explos ion close to the Solar 
System (wi thin a d iSiance of 20 pc). Although this 
assumption is not proven, some aspects of the calcula­
ted effects of a supernova explosion c lose to the Solar 
System (depletion of Ihe ozone layer, cooling of the tro­
posphere) were probably present with in the uppermost 
Permi an , but thi s can a lso be explai ned by huge vol­
canic eruptions that caused a volcanic winter (KOZUR, 

Geologia Croot ica 51(1. 

1998a). The explanation of the anoxia and increase in 
CO, by the high amount of dead biomass due to the 
mass extinction (DETRE e t aI., 1998) is sure ly incor­
reel. Nevertheless, the possible effects of a supernova 
explosion on the earth's biota should be taken into seri­
ous consideration, especially from the astronomy point 
of view: Can the gamma and roentgen radiation and lat­
er the corpuscular radiation and much later expanding 
gas and dust (as the assumed source of the microsphe­
rul es) from a supernova exp losion close to the Sun 
(within a distance of 20 or even of 10 pc) harm the 
earth' s biota despite the protection by solar wind, 
Earth 's atmosphere and magnetic field? 

Regardless of the inte rste llar or volcanic source, a 
thin horizon of strong enrichment of microspherules a 
linle be low the PTB could be a good auxilliary marker 
for the base of the Triassic , if it wi ll be di scovered in 
the same level in other and distant well datable sec tions 
(e.g. in NW and Central Iran). 

Terres trial causes for the PTB biotic crisis are pre­
fe rred. They may be a lso indicated by geochemica l 
changes. Geochemical evidence, mainly changes in the 
ratios of stable isotopes are commonly used as indica­
tors for the PTB biotic crisis (013C) or for environmen­
tal or climatic changes (8"0, 8" S, " Sr/" Sr). WANG et 
al. ( 1994) allributed the drop in 8 " C to a catastrophic 
coll apse of the marine primary productivity at the base 
of the Triassic. A produc tivity drop may contribute to 
the drop in 8" C, but there a re several other factors (d ia­
genesis, dolomitization, sed iment alteration by subaeri ­
a l exposure connected with a gap, oceanic anoxia) that 
influence the 0 13C curve as discussed in KOZUR 
(I 998a). For instance , in Ih e Se long section (Tibe t) , 
there is a strong negative shift of the ODC curve at a 
caliche bed (YIN et aI., I 996b) that is under- and over­
lain by beds with Gudadalupian cool-water conodonts, 
whereas no minimum in the OIlC occurs in the basal 
T riassic. For this reason, the caliche bed was regarded 
as an equivalent of the Boundary Clay immediatcely 
below the PTB in South Chin a (W ANG et a I. , 1989; 
M El , 1996). The strong drop of B"C reported by 
WANG ef al. (1994) from Brit ish Columbia may also 
be caused by sediment altera ti on during a long gap. 
Nevertheless, in many sections a primary minimum in 
the OUC curve is present at the very base of the Triass ic. 
However, it is not certain that this drop depends on the 
drop in bioproductivity a lo ne, or on other factors as 
well (or sometimes excl usive ly on the above menti oned 
other factors - FOSTER, 1997; KOZUR, [998a). At lhe 
GuadaJu pian - Lopingian boundary, where there is a 
strong drop in bioproducti vity, the 013e curve does not 
d rop but it may even rise s lig htly (HOLSER e l a I. , 
1991). The possi bility for slrat igraphic mis inte rpreta ­
ti on is much higher [or the onset of the drop in the 013C 
curve, or for its minimum, than for the biostratigraphi­
cally defined base of the Triassic (shortly discussed in 
secti on 2). Therefore, the proposal to use th e carbon 
isotope shift fo r the exact defin ition of the base of the 
Triass ic (NEWELL, 1994: minimum of the 8"C curve 



Kozur: Problems for Evaluation of the Scenario of the Pennian-Triassic Boundary ... 

as base of the Triassic; HOFFMANN et aI. , 1998: onset 
of the drop in the 8"C curve near the PTB as base of 
the Triassic) cannot be supported. Moreover, detailed 
investigations have shown that there are often two min­
ima of sim ilar magnitude of the ol3e curve in somewhat 
different stratigraphic levels, which excludes the use of 
the minimum of the oDe curve for definit ion of the 
base of the Triassic. The lower minimum lies in differ­
ent sections somewhat below, at or somewhat above the 
FAD of H. parvus. The onset of the drop in the 8 " C 
curve lies in the undoubtedly Permian Clarkina chang­
xing ensis - C. de/leela Zone. This was also stated by 
HOFFMANN et al. (1998), but explained that the con­
odonts are almost unaffected by the PTB ext inct ion 
event, which is not the case because the warm-water 
conodont fa unas disappeared. However, in the leve l, 
where the onset of the drop in the ODC curve occurs, 
there is not only a typical Permian conodont fauna, in 
Tethys dom inated by warm-water species of Clarkina , 
but also a typ ical Permian Pseudoliro/iles ammonoid 
fauna, a typical Perm ian foraminiferal fauna with latest 
fusulinids, typical Permian brachiopod, radiolarian and 
sponge faunas. The carbon isotope shift yields only 
auxiliary data for the definition of the base of the Trias­
sic which are neither as precise and invariably fixed to 
a precise time level nor situated at the level of the mass 
extinction or at the level of the appearance of the first 
Triassic foss ils after the mass extinction. 

A pronounced negati ve shift of 8" C in the lower­
most Triassic lies distinctly above the strong divers ity 
drop close to the PTB, and was therefore not connected 
to the fac tors that caused this diversity drop (KOZUR, 
1998a). Also the strong increase in 8" S during the Scy­
th ian is obviously not re lated to any environmental 
change in connection with the PTB biotic crisis. 

6. DATING AND COMPLEX EVALUATION OF 
THE EFFECTS OF THE EXTREMELY STRONG 

VOLCANIC ACTIVITY IN THE UPPER 
PERMIAN AND LOWERMOST TRIASSIC 

There is a perfect time correlation between the PTB 
biotic crisis and the strongest volcanism in Phanerozoic 
history. As shown by KOZUR ( 1998a), this volcanism 
had both direct effects, such as acid rain and a short 
volcani c wi nter, and indirect effects, including strong 
UV radiation as a result of the destruction of the ozone 
layer by an extremely strong eruption, and the onset of 
superanoxia, as well as combined direct and indirect 
effects, such as climatic changes. The extremely strong 
volcanism was obviously the most im portant factor of 
the PTB biot ic crisis. 

6.1. DATING OFTH E VOLCANISM AND ITS 
EFFECTS DURING THE VOLCANIC ACTIVITY 

The effects of the volcanic activi ty on the biotic 
divers ity around the PTB can only be estimated by very 
complex studies. First of all , the very exact dating of all 

\49 

occurrences is necessary to show whether volcanics, 
especially tuffs, are exactly contemporaneous over a 
large area and fit into the time interval of the biotic 
changes. This dating is easy and undi sputed for the 
tuffs that belong to a volcanic centre s ituated at the 
northeastern margin of the eastern Tethys adjacent to 
Panthalassa. In South China, very fine -grained altered 
tuffs of felsic- intermediate composition, with a constant 
thickness of around 6 cm can be found in the uppermost 
Dorashamian in all sections, where the deposition was 
below the storm-wave base. They are best investigated 
in the Meishan section (Zhejiang Province) and in the 
Shangsi section (Sichuan Province), about 1500 km to 
the west of Meishan (for details and complete refe­
rences see YIN et aI., 1996 and LAI et aI. , 1996). Fur­
ther tuff layers of the same chemical composition are 
present within the upper Dorashamian and in the lower­
most Triassic. The tuff layer a few centimetres below 
the FAD of H. parv"s is connected with the stronges t 
exti nction event, but some of the other tuff layers are 
also connected with extinctions. The northernmost kno­
wn occurrence of tuffs of an upper Dorashamian explo­
s ive fel sic-intermediate volcanism is in SE Siberia, 
about 2000 km NE of Meishan (ZAKHAROV et aI. , 
1995). There, about 65 m of tuffitic layers is present, 
but with sedimentary intercalations; nevertheless the 
thickness of the upper Dorasham ian volcanics is there 
much larger than in South China. The SE-S iberian 
occurrences were obviously closer to the eruption cen­
tres that were situated at the margin of Panthalassa, 
close to the northeastern margin of eastern Tethys. The 
South Chi nese altered tu ff layers are so fine-grained 
and thei r thickness is so constant over huge distances 
(about 2 million krn') that they may be part ly related to 
a fall -out of aerosol du st. This huge explosive fe lsie­
intermediate volcanism probably caused a volcanic 
winter in the uppermost Permian. The palaeolatitude of 
the eruption centre was in low northern latitudes. The­
refore, the effects of the volcanic winter and of the 
reduction of sunlight should be strongest in the low 
northern latitudes that correspond to a large part of the 
Tethys , to which the lates t Permian shallow warm­
water benthos was restricted (except for insular occur­
rences in the tropical part of Panthalassa). Only the 
southern part of eastern Tethys (with the Perigondwana 
margin) was situated in low to middl e southern lati ­
tudes. Thi s part of southern Tethys , and above all the 
insular areas within tropical Panthalassa, had the great­
est potential as a refuge for the shallow warm-water 
benthos. 

The age of the Siberian Trap was disputed for a long 
time. Regarding its post-Tatarian age, DOBRUSKINA 
& MOGUTCHEVA ( 1987) assigned it to the Triassic. 
In this case, the Siberian Trap would be without any 
importance for the PTB biotic crisis. SADOVNIKOV 
& ORLOVA (1994) and SADOVNIKOV (1997) ass i­
gned the larges t part of the Siberian Trap to the post­
Tatarian , bu t Late Permian Taimyrian Stage. The con­
chostracans and the new radiometric data fu lly confinn 



150 

the posI-Tatarian Late Permian age [or mos t of the 
Siberian Trap. The predominantly tuffitic Hungtukun­
skian Format ion of the Tungusska Basin conta ins Fa/­
sisco species (post-Tatarian conchostracan genus) that 
arc present in the Dalongkou sect ion cons iderable 
be low thc FAD of Lystrosaurus , and disappear 54 m 
bclow the FAD of Lystrosaurus in undoubtedly Upper, 
but not thc uppermost Permian beds. The followin g 
Puluranian basalt and related intrusives have. according 
to RENNE et al. (1995), an age of 250 (± 1.6) Ma. Bed 
25 in the Meishan section, 14-18 cm below the base of 
the Triassic detined by the FAD of H. parvus was dated 
by thc samc authors as 249.98 (± 0.20) Ma. Thc PUIll ­
fanian basalt started, therefore, somewhat before the 
PTB and straddled thi s boundary. The S iberian Trap 
covers 2.5 million km:'! , However, it is probably that in 
the subsurface of western Siberia, under a thick Meso­
Cenozoic cover, large areas arc also covered by the 
Siberian Trap, as the westernmost occurrence of the 
trap basalts is in the Urals. Thus, the area covered by 
the Siberian Trap may be fa r larger than 2.5 millio n 
km 2

, but a lready this area covered by thi ck tu ff layers 
followed by Oood basalt indicates the greatest vol canic 
activity in the Phanerozoic. 

The int ra-basalt ic layers of the Urals as the western­
most ext ension of the S iberian Trap volcanism were 
dated by TUZHIKOVA (1985) as lowermost Triass ic 
and would there fore post-date the PTB bioli c c ri s is. 
KOZUR ( 1989) agreed with TUZHIKOV A ( 1985) that 
the intra-basaltic layers of the Urals are post-Tatarian , 
but he pointed out that they are Upper Permian. A large 
part of the Zechstein pal ynodemes di scrimi nated by 
V1SSHER ( 197 1) occur in the intra-basaltic layers that 
correspond therefore to parl of the undoubtedly Pemli­
an Zechstein . Immediately below the lower volcanics, 
and in the lower part of the intra-basalti c sediment s, 
Lueckisporites virkkiae POTONIE & KLAUS , mainly 
norm Ae, is common (up to 16% of the sporomo rphs). 
Thi s part of the sequence is not younger than the asso­
ciation with dominating L. virkkiae norm Ac scnsu 
V1SSH ER that corresponds to the upper Zechstein 3. In 
the younger part of the intra-basaltic sediments Luecki­
spar/res cr. parvll s KLAUS (:::: L. virkkiae, norm Bc 
according to VISS HER, 1971) becomes dominant and 
then GUl!lIllapollenites sp. (L. virkkiae, norm C sensu 
VISS I-IER , 197 1) becomes increasingly frequent. Acco­
rd ing to the corre lation of the Zechstein sporomorph 
assoc ia tions with the international scale (KOZUR, 
1994b), the post-Tatarian intra-basaltic beds are upper 
Dzhulfi an to lower Dorashamian. The followi ng mai n 
phase of the volcanism began in the upper Dorashamian 
and las ted until the lowermost Triassic (Gangetian Sub­
stage). It straddles, therefore, the PTB. 

The two, close to the PTB contemporaneously acti ­
ve volcanic centres (Siberian Trap volcani sm and huge 
expl os ive volcanism at the northern Tethys/Panthalassa 
transition) , had surely a strong inJluencc on the world 
clim ate. Howeve r, there arc also other areas with tuffs 
and lavas close to the PTB. Dr. Spencer LUCAS , Albu-

Geolog ia Croatica 5 1/2 

querque, found altered tuff layers c lose to the PTB at 
the Dalongkou section in Sinkiang. Unfortunately, the 
material was confiscated and there fore neither radio­
metric nor geochemical investigations cou ld be carried 
out. If these volcanics are re lated either to the Siberian 
Trap or to the volcan ic centre at the transition between 
the northeastern Tethys and Panthalassa , thi s wou ld 
very much enlarge the areas with volcanic ashes or dust 
fall -out of one of these two volcanic centres. But even 
if they would belong to an independent volcanic centre, 
thi s would further enlarge th e areas a ffec ted in the 
uppermost Dorashamian by volcanic fall -out. 

Accord ing to KOZUR (1998a) , the long-lasting, ini­
tially mainly explosive Siberi an Trap volcanism (very 
intense from the uppermost Dzhulfian to lowermost 
Triass ic) caused some cli matic changes that harmed 
especially the terrestrial biola (severe climate, cooling 
in high and medium lat itudes, ac id rain). During this 
time, the tropical warm-wate r fau nas re trea ted to the 
tropical Tethys. Thus, in the med ium-lati tude Perigond­
wan a Sa lt Range, the Dzhul fian is charac terized by 
Tethyan wann-water conodonts. In the upperm ost Dzh­
ulfian and lowermost Dorashamian they were replaced 
by cool-water conodonts. The area with tropi cal warm ­
water faunas became in the Dorashami an very narrow 
and was restricted to the central and nort hern Tethys, 
where they remained highly diverse, and insular regions 
in the equatorial Panthalassa. 

The huge explosive felsic-intennediatc vo lcanism at 
the northeastern margin of Tethys a little be low the 
PTB caused according to KOZUR ( 1998a), a 3 - 6 
month volcanic winter in low lati tudes. T his period was 
long enough 10 kill the trop ica l warm-water faun as on 
the Tethyan shelves, but not long enough to bring the 
water temperature below the critical water-temperature 
for tropical warm -water faunas on the shelves of insular 
regions in the tropical part of Panthal ass a. T here, a 
large part of the warm-water faun as survived the PTB 
biotic crisis, and re-appeared on the Tethyan shelves in 
the upper Olenekian and in the Middle Triass ic as 
Lazarus taxa. 

A "side effect" of the huge volcani c eruption in the 
uppermost Permian that caused the volcanic winter, 
Ill ay be the destruction of the ozone layer by an espe­
ci a ll y violent e ruption. Aeroso ls and gases o f a huge 
explos ive e ruption could reach the ozone layer and 
deplete it. The consequence would be strong UV rad ia­
tion. The sudden di sappearance of the world- wide mass 
occurrences of fun g i cxactl y at the level of the huge 
volcanic erupt ion at the northeastern marg in o r Tethys 
is best explained by strong U V radi at ion that is lethal 
for fungi. S trong ly reduced sun light would favour rat­
her than harm the growth of fungi and also the cooling 
in a volcanic winter would not hann the Tympallocysta 
fun gal ass ociation becau se it is comm on both in th e 
tropi cal Tethyan and in the cold Bo rea l rea lm, and 
therefore adapted to both warm and cold climates. 

The biot ic express ions for a cooling event arc obvi­
ous (KOZ UR , 1998a). Mainl y the tro pi cal shall ow, 



Kozur; Problems for Evaluation oflhe Scenario of fhe Pennian-Triassic Boundary .. . 

warm-water fauna and flora as well as the plankton 
were affected by Ihe PTB biotic cri s is. The plankl on 
mass ext inction may also be re lated to a time of redu­
ced sunlight that would accompany a volcanic winter, 
and the radiolarian ext inct ion is probably partly related 
to oceani c anoxia. The mass extinct ion of tropical shal­
low-water biota could have been caused by a strong low 
latitude cooling or warming (the latte r is favoured by 
HALLAM & WIGNALL, 1997, for the lropical areas), 
bUI accord ing to KOZUR (l998a) a strong warming in 
low la titudes during the uppermost Permian can be 
excluded (st rong extinct ion of warm-water fa unas, but 
no pronounced extinction of marine cold!cool-water 
faunas and no cont inental extinction event in that strat i­
graphic level, contemporaneous equator-ward migrat ion 
of high latitude cool/cold-water faunas). Moreover, the 
strong g lobal warming al Ihe base of the Gandarian (= 
base of Dienerian) post-dates the PTB extinction event 
except the delayed extinct ion event of cool-water con· 
odonts. This global warming is directly related to the 
volcanic winter and the foregoing long· lasting Siberian 
Trap volcanism (see below). 

The important question is why the warm-water fau ­
nas from the tropical Panthalassa cou ld not return to 

Tethys earl ier. A vo lcanic winter, accompanied by a 
strong reduct ion of sunli ght, and the beg inning of the 
long- lasting, strong and violent Siberian Trap vo lca­
nism within the Dzhult1an (with the culmina tion of the 
volcanic activity in the upper Dorashamian and lower­
most Triassic) perfectly explain the observed extinction 
pattern affecting mainly the terrestrial communit ies 
(earlier than the marine faunas), the plankton, and the 
trop ical shallow, warm-water faunas. However, this 
event alone can not explain that the recovery occurred 
only in Ihe upper Scythian (upper Olenckian) and Mid­
dle T riass ic, several million years after the PTB biotic 
crisis. After the end of the volcanic winter, the tropical 
shelf communities wou ld recovt?r very fast by migration 
of warm-water faunas that had survived on the shelves 
of intra-oceanic islands (see above). Both the extinction 
on the tropical shelves and the recovery of the tropical 
warm-water biota would happen in geologically a very 
short time. In the geological record on ly a modera te 
ex tinction event and innovations of new faunal cle­
ments would be observed. This can be, for instance, 
observed after the midd le Carnian disappearance of the 
Tet hyan reef communi ties. 

6.2. DELAYED EFFECTS OF THE VERY INTENSE 
VOLCANISM AFTER THE END OF THE VOL­

CANIC WINTER AND AFTER THE END OFTH E 
SIB ERIAN TRAP VOLCANISM 

The reason for the long delay in the recovery of the 
wann·water benthos on the Tethyan shelves was the 
oceanic superanox ia which reached an unusually high 
level in the water column (e.g., as shown by dysaerobic 
conditions in the Mazzin Member and similar shallow­
water depos its above the storm -wave base, and black 

lSI 

shales in all oceans). The recovery of the Tethyan 
warm-water faunas coincides with the end of the long­
lasting lower-middle Scyth ian oceani c superanoxia in 
the sense of ISOZAKI ( 1994, 1997). 

As these superanoxia reached a leve l above the 
storm-wave base, they were an effect ive barrier against 
the migration of the warm -water benthos that had sur­
vived on the shelves around oceanic islands in the tropi­
cal Panthalassa (and perhaps partly also within eastern 
Tethys) to the tropical Tcthyan shelves. Moreover, such 
superanox ia also prevented the recovery of those radio­
larians (plankton) that lived benealh the uppermost, 
oxygenated water column . Thus, only the phytoplank­
ton (e.g. , acritarchs), whi ch occur in the uppermos t 
oceanic layer, recovered quickly after the volcanic win­
tcr (and the accompanyi ng slrongly reduced sunlight). 

The superanoxia were probably tr iggered by the 
unique volcanic activity in the Dzhulfian to lowermost 
Scythian in terval. The huge amounts of dust and sul­
phate aerosols caused strong precipitat ion in areas that 
were normally dry, both in the low and high latitude dry 
belts. As a result large inputs of fresh-water occurred in 
the high latitude cold seas, and this causcd a decrease in 
densi ty of the heavy cold surface water. The si nking of 
heavy cold surface water strongly dec reased or even 
ceased. T his down-s inking of heavy, cold surface water 
in the high latitudes is, however, the "motor" for the 
cold bottom water currents that bring highly oxygena­
ted co ld surface wate r v ia deep-water currents in the 
tropica l oceans, from where warm surface currents 
transport warm-water into high latitudes. If this oceanic 
current system di sappeared or became very weak, oce­
anic anoxia were established. 

T he lengthy dura tion of the oceanic anox ia was 
caused by a strong g lobal warming at the base of Ihe 
Gandarian (= Dicnerian) indicated by Ihe appearance of 
Tethyan warm-water biota in unusual high latitudes , 
such as Spitsbergen (WIGNALL et a I. , 1998; KOZUR, 
1998a). This caused a globally rather uniform cl imale 
during the upper Brahmanian (Gandarian Substage ;;;; 
Dienerian) , indicated by world-wide rather unifonn fau­
nas (e.g., Claraia faunas), and a low temperature gradi­
ent in the Tethyan and Boreal oceans, that for a lon g 
period prevented Ihe re-establishment of the cold bot ­
tom water currents. The temperature g radient between 
the Telhyan and Boreal rea lm became higher again dur­
ing the lower Oleneki an as indicated by increasing fau­
nal differences between these realms. The upper bound­
ary of the oceanic anox ia became lower during that 
time, but at least Pan tha lassa remained anoxic. In the 
upper Olenekian the co ld bottom-water currents were 
re-estab lished as indicated by the re-appearance of cold 
bottom-water palaeopsychrospheri c ostracod fauna s in 
Tethys. Contemporaneous ly, numerous Lazarus taxa 
among the shallow-water warm-water benthos migrated 
from their insular shelf relic areas withi n Panthal assa 
in to Tethys. 

The strong global warming at the base of the GaI1-
darian (= Dienerian) was also caused by the volcan ic 



152 

winter and the lengthy period of Siberian Trap volcan­
ism. The very strong explosive volcanism that caused 
the volcanic winter, and the foregoing as well as con­
temporaneous Siberian Trap produced huge amounts of 
the greenhouse gas CO2 • As mentioned above, the huge 
amounts of dust and sulphate aerosols that caused a vol­
canic winter favoured strong precipitation also in the 
dry hi gh latitude and in the arid low latitude girdles. 
The strong precipitations in the normally arid low lati­
tude gi rdles caused a strong increase in the total amount 
of water vapour in the earth's atmosphere. As water 
vapour is an effective greenhouse gas, this caused an 
additional strong greenhouse effect. As long as the 
Siberian Trap volcanism continued, this greenhouse 
effect was counterbalanced by dust and sulphate aero­
sols. However, the Siberian Trap volcanism ended dur­
ing the upper Gangetian, or at the latest by the top of 
the Gangetian because overlying sediments both in the 
Tungusska Basin and in the Urals yielded Cornia Rer­
mari (BEYRICH) and other vertexiids that are guide 
forms of the Gandarian. After the end of the Siberian 
Trap volcanism the greenhouse effect resulted in a 
strong global warming that may have been as high as 
6°C on average. as assumed by HALLAM & WIG­
NALL (1997). 

The high precipitation, also in the formerly dry low 
and high latitude girdle, is an assumption (based on 
knowledge about the huge explosive volcanic activity 
in the Upper Permian and especially around the PTB) 
that needs to be verified by geological and geochemical 
data. The strong increase in precipitation in the upper 
Dorashamian and lower Scythian may have caused (at 
least partly) the significant increase in the 87Sr/86Sr 
ratio that indicates a large increase in chemical weath­
ering triggered by increased humidity and atmospheric 
CO2 levels. It is striking that in the uppermost Dora­
sham ian and in the H. parvus and 1. isareiea zones of 
the lowermost Scythian, no signs of hypersaline seas or 
continental arid climate can be found globally, not even 
in areas that were previously very arid, as in the Ger­
mani c Basin or the Alps. In the Germanic Basin, the 
hypersaline sedimentation and salt precipitation in the 
Zechstein ended in the central basin and large fre sh 
water lakes with charophytes, Darwinula and conchos­
tracans developed, whereas in the marginal part arid 
desert or sabkha cond itions were replaced by fluviatile 
conditi ons. Thus, the predicted time interval of high 
precipitation in the normally arid low and high latitude 
girdles was really present during the uppermost 
Dorashamian C. meishanensis - H. latidentatus prae­
parvus Zone (starting with the very intense explosive 
eruption at the northeastern margin of the Tethys) and 
lowermost Triassk H. parVllS and 1. isarciea zones. 

Above the 1. isareica zone the climate fluctuated 
rapidly. In the red upper Sandy Claystone Member of 
the Calvorde Formation and in the contemporaneous 
Andraz Hori zon of the Southern Alps, the climate again 
bccame ar id in the low latitude dry girdles. In the upper 
Calvo rde Formation and Bernburg Formation (except 

Geologia Croatica 51!2 

for its uppermost part), and in the contemporaneous 
Seis Member of the Alps and Hungary, a rapid fluctua­
tion of predominantly humid to semi-humid with semi­
arid to arid climate can be observed. In the Bernburg 
Formation again a large fresh-water lake (or several 
large lakes) covered the central Germanic Basin, but 
periodically, the lake(s) dried out. The Seis Member 
was studied in detail for saIt-content f1uctuations in the 
northern Balaton Highland (Hungary), where deposi­
tion occurred in the marginal parts of the Seis shallow­
water sea. The shallow-water deposits are in general 
normally marine, wi th a rich Claraia fauna and con­
odonts. However, in some parts the fresh-water influx 
was so strong that on some bedding planes the marine 
fauna was replaced by a rich fresh- to brackish-water 
fauna with mass occurrences of in situ conchostracans 
(KOZUR, 1993; KOZUR & MOCK. 1993). In other 
beds hypersaline rocks with anhydrite nodules occur. 

Thus, the combination of climatic changes (princi­
pally the short cooli ng in the low latitudes due to a vol­
canic winter) and lower to middle Scythian superanoxia 
as the two main causes for the PTB biotic crisis were 
both caused by the unique large scale and violent explo­
sive volcanism in the uppermost Permian and lower­
most Triassic. 

7. GENERAL EXTINCTION AND RECOVERY 
PATTERNS CONNECTED TO THE PTB BIOTIC 

CRISIS 

Detailed knowledge of the exact extinction and re­
covery patterns in the Upper Permian and in the Lower 
Triassic (which can only be recognized by considera­
tion of the data and problems presented in sections 2-4) 
is most important for the reconstruction of a scenario of 
the PTB biotic crisis and the recognit ion of its causes. 
KOZUR (1998a) reported the following extinction and 
recovery patterns related to the PTB biotic crisis: 

The (siliceous) plankton (radiolarians). and the 
warm-water benthos (highly diverse Upper Permian 
warm-water benthos was restricted to the Tethys), 
nektobenthos and nekton were the most strongly 
affected. The production of organic silica dropped so 
far that there is a lengthy, global radiolarite gap in 
oceans from a little below the PTB to the base of the 
upper Olenekian. 

The cold-water faunas were either not, or slightly 
affected by the PTB biotic crisis. 

Faunas of temperate zones with seasonal climate 
were slightly to moderately affected. 

There was a delayed ext inction event in cold-water 
adapted faunas that survived the PTB without ext inc­
tion, tlourished and diversified in the lowermost Tri* 
assic after the extinction of the warm-water fauna in 
the Tethyan realm. 



Kozur: Problems fo r Evaluat ion of the Scenario of the Pennian-Triass ic Boundary ... 

The recovery time for the warm-water benthos and 
siliceous plankton was unusually delayed (about 5 
Ma) as this recovery occurred only in the upper 
Olenekian to Middle Triassic interval. 

The recovery of the nekton and nektobenthos was 
mostly rapid, afte r one conodont zone (H. parvus 
Zone that had a short duration <0.1 my). 

The productivity of the terrestrial plants dropped 
strongly and the recovery occurred mainly in the 
upper Olenekian and in thc Middle Triassic. 

Several extinction events occurred in the terrestrial 
faunas within the Upper Permian, considerably be­
low the marine PTB, and for different fo ss il groups 
at different stratigraphic levels. At the marine PTB, 
only a very slight extinction event can be observed in 
vertebrates, when "remnant" Permian form s (Dicyno­
don) disappeared. At, or close to, the often used con­
tinental PTB (FAD of Lystrosaurus) no extinction 
event of any terrestrial faunal element can be obser­
ved. 

Such terrestrial faunal elements mainly survived the 
PTB biotic crisis, which were able to survive some 
months of extrem e climatic conditions , including 
severe drought, cold or even freezing conditions in 
low latitudes by hibernation-type live stages (verte­
brates) or by drought- and freeze-resistant eggs (con­
chostracans). Good examples are the vertebrate Lys­
trosaurus which is known both from low latitudes 
and from high southern latitude areas with polar 
night, the conchostracan Fa/sisca which occurred 
both in low latitudes and in high northern latitudes 
within the Permo-Triassic polar circle, and the ostra­
cod Darwinu/a which lived in tropical areas and high 
latitudcs. 

Distinct terrestrial fl oral changes (that were not of 
local character) occurred during the upper Dora­
sham ian , when in most parts of the world the trilete 
cavate spores of lycopodiales became dominant, 
whereas several species of gymnosperme pollen dis­
appeared. Until the end of the Permian a low diversi­
ty terrestrial flora was establi shed and the terrestrial 
plant production became low. 

During the lower and middle Scythian the terrestrial 
plant production remained low (global coal gap). 

About 50 % of the genera that disappeared at the 
PTB re-appeared in the Olenekian - Middle Triassic 
interval (Lazarus taxa). Some of them had changed in 
generic level but had undoubtedly evolvcd from gen­
era that had disappeared at the PTB. In some groups 
the percentage of Lazarus genera is 90-100 % (e.g. , 
holothurians, scolecodonts). 

Only very few major fossil groups totally disap­
peared at the PTB (without Lazarus taxa). Most of 
these groups had a very low diversity and/or a regi­
onal restriction at the end of the Permian to Tethys or 

153 

even to eastern Tethys (trilobites, rugose corals, fusu­
linids). 

The PTB is preceded by mass occurrences of marine 
(and continental?) fun gi and the fungal spike ended 
abruptly a little before the PTB, in eastern Tethys at 
the base of the volcanic dust fall -out a littl e below 
the biochronologic PTB. 

The extinction was more severe in the northern than 
the southern hemisphere. 

8. CONCLUSION - A POSSIBLE SCENARIO 
FOR THE BIOTIC CRISIS AT THE PTB 

This scenario for the PTB biotic crisis originated by 
consideration of the data and probl ems presented in 
sections 2-7 and from earlier works (KOZUR, 1997c, 
1998a). It incorporates facts such as the severe Dzhul­
fian - Dorashamian climate in many parts of the world 
caused by the continent-ocean configuration and by the 
Siberian Trap volcanism; the extinction event at the 
Guadalupian -Lopingian boundary that restricted most 
of the affected warm -water faunas to Tethys; and the 
Permian northward drift of Pangaea leading to a Middle 
and Upper Permian cooling of the Boreal area which 
caused a successive Middle Permian extinction of 
warm-water benthos and an interruption of the ex­
change of warm-water benthos between the Tethys and 
western North America during the Guadalupian. 

The Permian northward drift brought large parts of 
Pangaea into the tropical -subtropical belt during the 
Middle -Late Permian resulting in rather severe climatic 
conditions over large parts of Pangaea during the Upper 
Permian, such as aridity and strong daily and seasonal 
temperature variations. Part of the fauna adapted to sur­
vive several months of very severe climate (long drou­
ght, low winter temperatures below freezing point in 
areas with hot or warm summers). At the same time, 
northern Pangaea reached the Boreal realm and the 
Middle-Upper Permian climate became colder and 
colder. Thi s lead to extinction of major warm-water 
fo ssil groups in the Arctic long before the PTB , as 
shown by the disappearance of the fusulinids at the base 
of the Guadalupian. The faunal exchange of warm­
water benthos between Tethys and the westem shelf of 
America was interrupted. Therefore, a strong provin ­
cialism developed with different shallow, warm-water 
faunas on the western shelf of America and in Tethys. 
A very rapid and extensive regression at the Guadalupi­
an-Lopingian boundary destroyed the habi tats of large 
shelf areas (e.g., the Delaware Basin of southwestern 
North America changed into a hypersaline bas in) , In 
other basins, like the Phosphoria Basin, the warm-water 
fauna was additionally harmed by wide-spread upwel­
ling of cold boltom water. Connected regional extinc­
tions led to the disappearance of fusulinids on the west­
ern America warm -water she lf during the lowermost 



154 

Loping ian. As benthi c warm-water faunas could no 
longer mi grate between Tethys and western North 
America through the southern margin of the Boreal sea, 
major groups such as the fu sulinids were restricted to 
the Tethys in the upper Dzhulfian and Dorashamian. 
This is a lso the case for the warm-water Clarkina sub­
carinala conodont lineage and for most groups of the 
reef communit ies. 

Beginning in the middl e Dzhulfian , the climate 
became periodically morc severe by the intluence of the 
( in that time) largely explosive Siberi an Trap volcan ­
ism. The eruptions became stronger and stronger during 
the Dorashamian. The reduecd strength of sunlight due 
to the presence of dust and sulphate aerosols favoured 
the development of marine (and continental?) fungi that 
became more and more common during the late Dora­
shamian (Tympanicys/a associat ion). Acid rain hanned 
the gymnosperm forests and most other plants, but did 
not influence swamp fl oras with Lycopodiales that were 
adapted to acid soi l. Therefore in many parts of the 
world lycopod ialcs noras, as indicated by increasing 
amounts of trile te cavatc spores became common and in 
many places dominant , whereas the amount of gym­
nosperms decreased in the uppennost Permian. Repeti­
tive very short periods of cooling in low latitudes, COI1-

nected with dust and sulphate aerosols from the S iber­
ian Trap vo lcanism, led to a drop in the diversity of ter­
restr ial vertebrates and fresh water faunas to the upper­
most Permian. The larger te rres trial te trapods were 
affe c ted first whil e the conchostracans with drought ­
and freeze-res istant eggs were affected last. By these 
stepwise extinctions of different terres trial faunal gro­
ups, in the upper Dorasham ian a low diversity terrestri ­
a l and fresh-water fauna was present, in which form s 
prevailed that could survive severe climat ic conditions, 
including short cooler periods in low latitude areas 
(Lys trosaurus among the te rrestrial vertebrates, con­
chost racans, Danvillula among the freshwater ostra­
cods) . Forms adapted to a permanentl y warm climate 
become rarc (Dicynodon). The cold climate in the Bore­
al realm and a regress ion followed by a transgress ion 
lead to the es tablishment of a very low-diversity fauna 
during the upper Dorashamian O/ocems COllcaVl/In and 
O. boreale zoncs (the uppermost part o[ thc latter zone 
s .1. be longs to the earlies t Triass ic H. parvlls Zone). 
Highly diverse marine warm-water faunas were at that 
time res tri c ted to Tethys, moderately diverse marine 
faunas occurred on the temperate Perigondwana 
shelves. 

During the latest Dorashamian and earliest Triassic, 
around 252-250 Ma ago, the effusion of the Siberian 
Trap basaliS covered an area of at least 2.5 million km 2

, 

possi bly eve n 4~5 milli on km 2
• Furthe rmore in the 

northern hemisphere a huge highly explosive fe lsic to 
intermediate volcan ism occurred at the no rtheastern 
Tethys - Panthalassa margin. Huge amounts of dust and 
sulphat e ae rosols were re leased into the atmosphere, 
and in the eastern Tethys a fall -o Llt of volcanic dust 
over an area of a t least 2 million km2 occ urred. Dust 

Geologia Croalica 51/2 

and sulphate aerosols lead to a drastic drop in tempera­
ture especially in low lat itudes (Tethys!), which lasted 
about 3-6 months (volcanic winter w ith conditions s i­
milar to those calculated for a thermo-nuclear winter). 
Drastically reduced sunlig ht at the earth 's surface and 
also a drop in water temperature on the Tethyan shelves 
strongly affected the phytoplankton , the basic e lement 
of the marine food-chain. Skeleton-bearing p lankton 
(Radiolari a) that li ved in different watcr depths was 
additionally affected by the onset of the oceanic anoxia. 
The Tethyan shelves, the rcfuge for most of the latest 
Permian warm-water benthos were coo led below the 
temperatures critical fo r reef communiti es, and the 
entire warm -water benthos, but in many places al so 
most of the wam,-water nekton or nektobenthonic fau ­
nas (e.g. , wann-water conodonts) became extinct on the 
shelves. Thi s climatic catastrophe was more severe in 
the northern hemisphere, where the two huge volcani c 
centres were situated , and especially severe in low 
northern latitudes, where the centre of the huge explo­
sive felsic-intermediate volcanism was located. 

The cold-water adapted fauna of the Boreal realm 
was not affected by thi s cl imat ic catastrophe. The tem­
perate to coo l-water Peri gondwana fauna was moder­
ately affected because there was no tropical warm ­
water benthos, and the climatic catastrophe was not as 
severe as in the northern hem isphere. A bipolar fauna 
was es tablished , as O/oceras from the Boreal realm 
invaded thi s area close to the PTB , probably in connec­
tion with the volcanic wi nter. 

A global warming within the lower Scythian (indi­
rectly re lated to the strong volcanism), which occurred 
a t the base of the Gandarian (= Dienerian), caused the 
extinction o f those co l d~water adapted taxa that were 
not affec ted by the vol cani c winter and flouri shed 
therefore during the uppermost Dorashamian and low­
ermost Tri ass ic in Tethys, where they occupied all 
those biotopes, from which the Te thyan warm-water 
fauna had disappeared. 

Continuing acid rain in the Gangeti an (in connec­
tion with the continuing S iberian Trap volcanism) and 
the subsequent Gandarian g lobal warming may be thc 
reasons fo r the delayed recovery o f the low latitude 
continental flora , especiall y in areas with a hot seasonal 
climate. 

The low diversity uppermost Dorashamian terrestri ­
al and fresh water fauna , to a large extent a lready adapt­
ed to shorter periods of sevcre climate (freezing tem­
peratures or drought) surv ived to a large degree, afte r 
those faunal e lement s thai were adapt ed to a perma­
nent ly warm climate had died out earli e r during the 
Dzhulfian and Dorashamian. Only rare las t representa~ 

tives of the latter fauna , like Dicynodoll , became exti nct 
close to the PTB. 

The oppo rtunistic swamp Dora was no t greatl y 
affected by a short- lasting temperature drop in low lati ­
tudes and acid rain, but many Permian gymnosperm s 
di sappeared. In the eastern Tethyan humid-tropical 
Cathays ia province , rather distinct abrupt changes in 



Kozur: Problems for Evaluation of the Scenario of the Pennian-Triassic Boundary ... 

the flora can be observed. The tropical Filicales-Pteri­
dospermophyta "rain forest" flora largely disappeared 
and the tropical highland nora with dominating gym­
nospenns survived. Therefore, the Cathaysia flora beca­
me rich in gymnosperms (sudden increase in bisaccate 
pollen) during the biotic crisis in connection with the 
volcanic dust fall-out, whereas in other floral realms the 
spores (especially of the Lycopodiales swamp flora) 
became dominant against the bisaccate pollen . As a 
whole, both in the terrestrial plant diversity and terres­
trial plant bioproduction a minimum began with the 
volcan ic winter within the latest Dorashamian (begin­
ning of the world-wide coal gap) and the terrestrial 
plant diversity /bioproduct ivity remained very low dur­
ing the lower and middle Scythian (coal gap). Only in 
the upper Scythian (upper Olenekian) the terrestrial 
land plant diversity recovered, but the first "post-crisis" 
coals are known only from Middle Triassic beds. 

The explosive eruptions at the northeastern Tethyan 
volcanic centre were so strong that even the ozone layer 
was depleted. Duc to the resulting strong UV radiation, 
the booming of marine (and continental?) fungi sudden­
ly ends at the base of the volcanic dust fall-out in eas t­
ern Tethys and in contemporaneous levels in other parts 
of the world. 

The drop in waler temperature in the central tropical 
Panthalassa was not severe enough to kill the warm­
wate r benthos on the narrow shelves of insular areas, 
where many warm-water taxa survived . However, these 
forms could not migrate to the faunistically depleted 
Tethyan shelves because of the wide-spread oceanic 
anoxia that reached in an unusually shallow level above 
the storm-wave base. Therefore, the recovery of the 
warm-water benthos on the Tethyan shelves was dela­
yed [or about 5 my until the end of the superanoxi a in 
thc upper Olenekian and Middle Triassic. As the sha[· 
low-water shelves around oceanic islands are unstable 
biotopes, many relic biotopes were destroyed during 
this period. Thus, finally, the strongly dclayed recovcry 
led to a delayed extinction, but many taxa survived this 
lengthy interval of relative isolation. After the end of 
the oceanic anoxia about 50 % of the genera that disap­
peared at the PTB re-appeared unchanged or slightly 
changed during the upper Olcnekian and Middle Trias­
sic. This reappearance of Lazarus taxa is followed by a 
radiation of the warm-water benthos during the Middle 
and Upper Triassic. 

This sccnario exp lain s nearly all the details of the 
cxtinction patterns in continental and marine biotopes 
as well as the delayed recovery and the high percentage 
or Lazarus taxa that re-appeared during the upper Ole­
nekian and Middle Triassic. Only two facts arc difficult 
to explain. One is the strongly delayed recovery of the 
siliceolls plankton (radiolarians) that began only in the 
uppcr Olenekian. This delayed recovery can partly be 
explained by the oceanic superanoxia because not all 
Palaeozoic-Mesozoic radiolarians lived in the upper­
most, anoxia-free water column. However, those radio­
larians that lived near the surface of the oceans should 

155 

have recovered very quickly as an anoxic ocean is espe­
cially nu trient-r ich (HALLAM & WIGNALL, 1997). 
However, these radiolarians, to which the Oertlispongi­
dae and a part of the Entactinaria belong, did also not 
recover before the late Olenekian or the Middle Trias­
sic. A possible explanation for this is that nearly all 
skeleton-bearing Radiolaria became ext inct ncar the 
PTB, and the Triassic radiolarian fauna developed anew 
from skeleton-less or spicular radiolarians (KOZUR et 
aI., [996a). 

Superanoxia cannot explain the delayed recovery of 
the high productivity of terrestrial plants that also 
occurred in the upper Olenekian. In low latitudes with a 
hot seasonal climate this may be explained by a strong 
warming within the Gandarian (= Dienerian). However, 
such a global climate would favour the terrcstrial pl ant 
productivity at high latitudes, but there the productivity 
also remained low. Thus, the high latitude Gondwana 
areas with Permian coals have no Lower Triassic coals, 
which do not exist anywhere else either. In the Gange­
tian, the terrestrial plant community may have been 
harmed by acid rain triggered by the conti nuing Siber­
ian Trap volcanism, but in the Gandarian and lower 
Olenekian this volcanism was finished, and no distinct 
recovery of the terrestrial plant productivity can be 
observed in that time. 

A possible explan ation for the delayed recovery of 
the terrestrial plants is the strong ext inction event of the 
fungi in the uppermost Permian, most probably caused 
by strong UV radiat ion due to destruction of the ozone 
layer. For dense vegetation comparable with tropical 
rain forest, the activity of microscopic fung i is decisive 
important. Without or with strongly reduced activities 
of these fungi such dense vegetation cou ld not sUfvivc 
for longer time because the recycling of the organic 
matter would be very much disturbed, and the soil 
would become too POOf for a dense vegetation. 

As the recovery of the terrestrial plants, the plank­
tonic radiolaria ns and of the warm-water benthos 
occurred contempo raneously in the upper Olenekian 
and Middle Triassic, there may sti ll be some unknown 
factors that prevented the lower and middle Scythian 
recovery of the biota additional to the marine anoxia. 

Some of the factors that lead to the PTB biotic crisis 
are today caused by man-made destructions of the envi­
ronment, such as increase of atmospheric CO2, air pol­
lution, begi nning destruction of the ozone layer, pollu­
tion of the sea, and destruction of the tropical rain 
forests. As the study of the Phanerozoic biodiversity 
has shown, the biosphere recovers vcry fast, if the 
harmful factors disappeared. This, however, is possible 
only until a certain level of environmental and bios­
phere destruction. Beyond this level, self-strengthen ing 
effects of the environmcntal and biosphere destruction 
come into existence that can lead to an environmental 
catastroph and biotic crisis (mass extinction etc.). The 
recent extinction rate, which is caused mainly by envi­
ronmental and biotic destruction by negative effects of 
human activities, is very high. The estimations are 



156 

between a daily extinction rate of74 species (SEPKOS­
KI , 1997) and 150 species (EHRLICH & WILSON, 
199 1). According to BRIGGS (1994) the extinction rate 
is today highest in the Phanerozoic. Even at the lower 
est im ation , the present extinction rate is close to the 
ex tinc tion rate around the PTB. Deci sive important 
parts of the biosphere, such as marine plankton as the 
prim ary source of the food chain, are not yet affected in 
a g lo bal scale. However, this may happen in nea r 
future, if the destruction of environment and biosphere 
co ntinue in the present level or even grow. Then the 
leve l wi ll be reached, at wh ich the self-strengthening 
and back feeding processes of a biotic crisis will domi­
nate . Thus, protection o f the environment and of the 
biosphere diversity may become soon a question of sur­
vival for the mankind. 

Acknowledgements 

Prof. Dr. I-lei fried MOSTLER, Innsbruck and Pro f. 
Dr. lasenka SREM AC, Zagreb, improved this paper by 
very care ful reviewing . I am also very gratefu l to Dr. 
Julie ROBSON, Southminster, for her language ed iting 
and very usefu l comments. 

9. REFERENCES 

ADAMCZAK, F. (1969): On the question of whether 
the palaeocope ostracods werc filter-feeders .- In: 
NEA LE, l.W. (cd. ): The taxonomy, morphology 
and ecology of Recent Ostracoda. Oliver & Boyd, 
93-98, Edinbu rgh. 

ALBERTI, von, F. ( 1834): Bei trag zu einer Mono­
graphc dcs Bunt en Sandste ins, Musche lkalks und 
Keupers und die Verbindung dieser Gebilde zu ein­
er Formation.- Verlag der J.G. COTTA 'schen Buch­
handlung, Stuttgart and TUbingen, 366 p. 

BALME, B.E. ( 1979): Palynology of Permian-Triass ic 
boundary beds at Kap Stosch, East Greenland. ­
Medd. Gr0n l. , 200/6, 1-37. 

BAUD, A., ATUDOREI, V. & SHARP, Z. (1996): Late 
Permian and Early Triassic evo lution of the north­
ern Indi an margin: carbon isotope and seq uence 
stratigraphy.- Geodinamiea Acta, 9/2, 57-77. 

BOOMER, l. & WHATLEY, R. (1992): Ostracoda and 
dysacrobia in the Lower Jurass ic of Wales : The 
reconstruct ion of past oxygen levels.- Palaeogeogr. , 
Palaeoelimatol. , Palaeoecol. , 99, 373-379. 

BRIGGS , J.C. (1994): Mass extinctions: faelor falla­
ey?- In: GLEN, W. (ed.): The mass exti nction deba­
tes: How science works in a crisis. Stanford Univer­
sity Press, 230-236, Stanford. 

CHENG , Z., HAN , Y. , HOU , J., LI, J. , LT, P. , LT, Y. , 
LTU, S., LIU, Y. , QU, L., SHEN, B., SUN, S., WU , 

Geologia Croatica 5 1/2 

S. , XIAO, S., YANG, J. & ZHANG, Z. (1989): 
Research on the boundary between Permian and 
Triassic strata in Tianshan Mountain of China.- Chi­
na Ocean Press, Beijing, 176 p. 

DAGYS, A. (1994): Correlation of the lowermost Tri­
assie.- Albertiana, 14,38-44. 

DAGYS, A. & ERMAKOV, S. ( 1996): Induan (Trias­
sic) ammonoids from north -eastern As ia.- Rev. 
Paleobiol., 15/2,401-447. 

DETRE, Cs., TOTH, I., DON, Gy. , SOLT, P., GUC­
SIK, A. , KISS, A.Z., UZONYI , I. & BERCZI, Sz. 
(1998): A nearby supernova explosion at the Permo­
Triass ic boundary.- 23rd Symposium on Antarctic 
Meteorites, Juni 10-1 2, 1998, Nationa l Institute 
Polar Research, 23-24, Tokyo. 

DIENER, C. (19 12): The Triass ic of the Himal ayas.­
Mem. Geol. Surv. India, 36/3, 176 p. 

DING, M., ZHANG, K. & LAI , X. ( 1995): Discussion 
on lsarcicella parva of the Early Triassic.- Palae­
oworld , 6, 56-63. 

DOBRUSKINA, LA. & MOGUTCHEVA N.K. (1987): 
About the age of the Tungusska Basin volcanics. ­
Geol. Geophys., 1987/1 ,29-36 (in Russian). 

EHRLICH, P.R. & WILSON, E.O. (1991): Biodiversity 
studies: science and poliey.- Science, 253, 58-62. 

ERWIN, D.H. (1993): The great Palaeozoic crisis. Life 
and death in the Permian.- Columbia Univers ity 
Press, New York, 327 p. 

FOSTER, e.B. (1997): The Permian-Triassic boundary 
in Aus tralia: where is it and how is it exprcssed?­
In: SHI, G.R. (cd. ): The Pemlian of eastern Tethys: 
biostratigraphy, palaeogeog raphy and resources. 
Abstracts, Deakin University, Technica l paper, 3, 
51-52, Melbourne. 

GR IESBACH, e.L. (1880): Pal eontological notes on 
the Lower Trias on the Himalayas.- Rec. Geol. 
Surv. India, 13/2, 94-113. 

HALLAM, A. (1994): The earliest Triass ic as an anox­
ic event , and its relationship to the e nd-Palaeozoic 
mass extinction.- Canadian Soc. Petrol. Geo !. , 
Mem. , 17, 797-804. 

HALLAM, A. & WIGNALL, P.B. ( 1997): Mass exti­
nctions and their aftermath.- Oxford Univers ity 
Press, Oxford-New York-Tokyo, 320 p. 

HAO, W.e. ( 1992): Early Triass ic marine ostracods 
from Guizhou.- Acta Mieropaleon!. Siniea, 9/1 , 37-
44. 

HENDERSON, e.M. (1993): Arc Permian-Tri assic 
boundary events diachronous? Ev idence from the 
Canad ian Arctic.- Carboniferous to Jurass ic Pangea, 
Program and Abstracts, 136, Calgary. 

HENDERSON, e.M. & BAUD, A. (1996): Correlation 
of the Pennian-Triassic boundary in Arctic Canada 



Kozur: Problems for Evaluation of the Scenario of the Pemlian-Triassic Boundary ... 

on the basis of molluscan and conodont distribu­
tion.- 30th International Geological Congress, Abs­
tracts, 2, 63, Beijing. 

HOFFMANN, A., GRUSZCZYNSKI, M., MALKO­
WSKI, K. & SZANIAWSKI, H: (1998): Should the 
PermianfTriassic boundary be defined by the carbon 
isotope shift?- Acta Geol. Polonica, 48/2,141-148. 

HOLSER, W.T., SCHONLAUB, H.P., BOECKEL­
MANN, K., MARGARITZ, M. & ORTH, C.L 
(1991): The Permian-Triassic of the Gartnerkogel-l 
core (Carnic Alps, Austria): synthesis and conclu­
sions.- Abh. Geol. B.-A., 45, 213-232. 

IGO, H. (1996): Silurian to Triassic conodont biostra­
tigraphy in Japan.- In: First Asian Conodont Sym­
posium. Acta Micropaleont. Sinica, 13/2, 143- 160. 

ISOZAKI, Y. (1994): Superanoxia across the Permo­
Triassic boundary: Record in accreted deep-sea 
pelagic chert in Japan.- Canadian Soc. Petrol. Geol., 
Mem. 17,805-812. 

ISOZAKI, Y. (1997): Permo-Triassic boundary supera­
noxia and stratified superocean: Records from lost 
deep-sea.- Science, 276, 235-238. 

JIN, Y., SHEN, S., ZHU, Z., MEl, S. & WANG, W. 
(1996): The Selong section, candidate of the global 
stratotype section and point of the Permian-Triassic 
boundary.- In YIN, H. (ed.): The Palaeozoic-Meso­
zoic boundary. Candidates of global stratotype sec­
lion and point of the Permian-Triassic boundary. 
China Un ivers ity of Geosciences Press, 127-137, 
Wuhan. 

KOIKE, T. (1996): The first occurrence of Griesbachi­
an conodonts in Japan.- Trans. Proc. Palaeont. Soc. 
Japan, N.S. 181,337-346. 

KOTLY AR, G.V., KOZUR, H. & ZAKHAROV, Yu.D. 
(1993): The Transcaucasian sections Dorasham 2 
(Azerbaidzhan) and Sovetashen (Armenia), two ca­
nd idates for prr boundary reference seclions.- Afbe­
rtiana, 12,36-38. 

KOZUR, H. (1973): Die Bedeutung der triassischen 
Scolecodonten insbesondere fiir die Taxonomic und 
Phylogenie del' fossilen Eunicida. Hat sich die Syn­
these von "ort hotaxonomischen" und "parataxono­
mischen" System in del' Praxis bewahrt?- Mitt. Ges. 
Geol. Bergbaustud., 21, 745-776. 

KOZUR, I-I. (1985): Biostratigraphic evaluation of the 
Upper Palaeozoic conodonts, ostracods, and holo­
thurian sclerites of the BUkk Mrs., Part II: Upper 
Palaeozoic ostraeods.- Aeta Geo!. Hungar., 28/3-4, 
225-256. 

KOZUR, H. (1989): Thc Pcrmian-Triass ic boundary in 
marine and continental sediments.- Zentralblatt fijr 
Geologie und Palaontologie, 1988/11-12, 1245-
1277. 

157 

KOZUR, H. (1991): Permian deep-water ostracods 
from Sicily (Italy). Part 2: Biofacial evaluation and 
remarks to the Silurian to Triassic paleopsychros­
pheric ostracods.- Geol. Palaont. Mitt. Innsbruck, 
Sonderbd., 3, 25-38. 

KOZUR, H. (1993): Range charts of conchostracans in 
the Germanic Buntsandstein.- In: LUCAS, S.G. & 
MORALES, M. (eds .): The nonmarine Triassic. 
New Mexico Mus. Nat. Hist. & Sci., Bull., 3, 249-
253. 

KOZUR, H. (1994a): The PermianfTriassic boundary 
and possible causes of the faunal change ncar the 
PfT boundary.- Permophiles, 24, 51-54. 

KOZUR, H. (1994b): The correlati on of the Zechstein 
with the marine Standard.- Jb. Geol. B.-A., 137, 85-
103. 

KOZUR, H. (1995a): Permian conodont zonation and 
its importance for the Permian stratigraphic standard 
scale.- Geol. Palaont. Mitt. Innsbruck, 20, Festsch­
rift zum 60. Geburtstag von Helfried MOSTLER, 
165-205. 

KOZUR, H. (1995b): Some remarks to the conodonts 
Hindeodus and Isarcicella in the latest Permian and 
earliest Triassic. - Palaeoworld, 6, 64-77. 

KOZUR, H. (1996a): Some remarks to the Permian 
standard scale.- Guadalupian II, Alpine, Texas, 
April 10-13 , 1996, Abstracts, 7-11, 13, 14, Wash­
ington. 

KOZUR, H. (1996b): The conodonts Hindeodus, Isar­
cieella and Sweetohindeodus in the uppermost Per­
mian and lowermost Triassic. - Geol. Croatica, 49/1, 
53-96. 

KOZUR, H. (1996c): The Permian-Triassic boundary 
(PTB) in marine and continental beds - possible ca­
uses for the PTB biotic crisis.- 30th IGC, Abstracts, 
2,55, Beijing. 

KOZUR, H. (1996d) : Changes in marine ostracod fau ­
nas at the Permian-Triassic boundary.- 3eme Con­
gres Europeen des Ostracodologislcs - Paris - Bier­
ville, 8-12 July 1996,40, Paris. 

KOZUR, H. (1997a): Pelagic Permian and Triassic of 
the Western Tethys and its paleogeographic and 
stratigraphic sign ificance.- 48. Berg- und Hiitlcn­
mannischer Tag, Abstract, 21-25, Freiberg. 

KOZUR, I-I. (1997b): The effects of the Permo-Triassic 
boundary biotic crisis on different faunal groups and 
its possi ble causes.- 13th International Symposium 
on Ostracoda IS097 , Abstract Vol., 31, London. 

KOZUR, H. (1997c): Possible scenario for the biotic 
crisis of the Pennianffriassic boundary.- UNESCO­
IOCP Proj ect #335 "Biotic recoveries from mass 
extinctions", final conference "Recoveries '97", 18-
22, Praha. 



158 

KOZUR , H. (1997d): The Permian conodont biochro­
noloy: Progress and problems.- In: S HI , G.R. (cd.): 
The Permi an of eastern Tethys: Bios tratigraphy, 
Palaeogeography and Resources. Abstracts, Deakin 
Univ., Technical paper, 3, 79-82, Melboumc. 

KOZUR, 1-I.W. (l998a): Some aspects of the Pcrm ian­
Triassic boundary (PTB) and of the possible causes 
for the biot ic cri sis around this boundary. - Palaeo­
geogr. , Palacocl imatol. , Palaeoeeol. , 143 , 227-272. 

KOZUR ( 1998b): Upper Triassic Punciacca , the con­
necting link between the Palaeozo ic to Lower Trias­
sic Kirkbyacea and the Cretaceous to Cenozoic Pun­
ciacca.- Bu ll. Cent re Rech. , Elf Explor. Prod. Mem., 
20,257-269. 

KOZUR, H.W., KAYA , O. & MOSTLER, H. (1996a): 
Firs t ev idencc of Lower to Middle Scythi an (Die­
nc ri an - Lower Olenekian) radi o larians from the 
Karakaya Zone of north western Turkey.- Geo!. 
Palliont. Mit t. Innsbruck, Sonderbd ., 4, 271-285. 

KOZUR , H. & MOCK, R. (1974): Holothurien-Sklerite 
aus de f Trias def Siowakei und ihre stratigraphische 
Bedeutu ng. - Geol. Zborn. , Geol. Carpathica, 25/1, 
11 5- 145. 

KOZUR , H. & MOCK, R. (1993): Thc importance of 
conchostracans for the correlation of continental and 
marinc bcds.- In : LUCAS , S.G. & MORALES , M. 
(cds.) : The nonmarine Triass ic . New Mexico Mus. 
Nat. I-list. & Sci., Bull. , 3, 261 -266. 

KOZU R, 1-1., RAMOYS , A. , WANG, c.Y. & ZAKHA­
ROY , Y. (1996b): The im portance of Hindeodus 
parvu s (Conodonta) fo r the de fini tio n o f the 
Permian - Triassic boundary and evaluation o f the 
proposed sections for a g lobal stratotype section and 
poin t (GSSP) for the base of thc Tri assic_- Geolo­
gija, 37/38, 173-213, LjUbljana. 

KOZU R, J-1 . & SEIDEL, G. (1983) : Die Biostrati gra­
phie des unteren und mittleren Buntsandsteins unter 
besonderer Berlicks ichtigung der Conchostracen. ­
Z. gcol. Wiss., 11 /4, 429-464. 

KRYSTYN , L. & ORCHARD, M.J. (1996): Lower­
most Triass ic ammonoid and conodont biostratigra­
phy of Spit i, India.- Albertiana, 17, 10-21. 

LAI, X. , DING, M. & ZHANG, K. (l 996a): The signif­
icance of the discovery of Isarcicella isw·cica at the 
Meishan Pe rm ian-Triassic boundary stratotype sec­
tion in Changx ing, Zhejiang Provincc.- Exploration 
of Geoscicnces, 11 ,7- 11. 

LAI, X. , YANG , F. , HALLAM, A. & WIGNALL, P.B. 
(1996b): The Shangsi section, candidate of the Glo­
bal Stratotype Section and Point of Permian-Triass ic 
Boundary.- In : YIN, H. (ed.): The Palacozoic-Meso­
zoic boundary. Candidates of global stratotype sec­
ti on and point of the Permian-Triass ic bound ary . 
China Un iversit y of Geosc iencs Press, 11 3-124 , 
Wuhan. 

Geologia Croatica5 1/2 

LET HI ERS, F. & WHATLEY, R. ( 1994): The use of 
Ostracoda to reconstruct the oxygcn Icvcls of Late 
Palaeozoic oceans.- Marine M icropa leont. , 24, 57-
69. 

LETHIERS, F. & WHATLEY, R. (1995): Oxygenat ion 
des caux et ostracodes filt reurs : appl icati on au 
Devonien-Dinantien.- Geobios, 28/2, 199-207. 

LOZOYSKY, Y.R. (1993): The most comp lcte and fos­
sili fe rous Lower Triass ic sec ti on of the Moscow 
Syneclise: The best candidate fo r a nonmarine g lob­
al timc seale.- In: LUCAS, S.G. & MORALES , M. 
(cds.) : The nonmarine Tri ass ic . Ncw Mex ico Mus. 
Nat. Hist. & Sci., Bull. , 3, 293-295. 

LUCAS, S.G. (1 993): Vertebrate biochronology of the 
Triassic of China.- In : LUCAS, S.G. & MORALES , 
M. (cds.): The non marinc Triass ic. New Mex ico 
Mus. Nat. Hist. & Sci., Bull. , 3, 30 1-306. 

MATSUDA, T. (1 98 1): Early Triassic conodonts from 
Kashmir, India. Part I: Hindeodus and Isarcicella.­
l ournal o f Geosciences, Osaka C it y University, 
24/3,75 -108. 

MEl, S. (1996): Restudy of conodonts from the Penni­
an-Triass ic boundary beds at Se long and Meishan 
and the natural Permian-Tri ass ic bo undary .- In: 
WANG, H. & WANG , X. (eds.): Centennial Memo­
ri al Yolume of Pro f. Sun Yunshu: Palaeontology 
and Stratigraphy . China Uni versity of Geosc iences 
Press, 14 1-148, Beijing. 

MOSTLER, H. (1969): Entwicklungsreihen triass ischer 
Holothurien-Sklerite.- Alpenkundl ichc Stud ien, 7, 
53 p. 

MOSTLER, H. (1973): Holothuriensklerite der alpinen 
Trias und ihrc strati graphische Bedeutung. - Mitt. 
Ges. Geol. Begbaustud ., 2 1,729-743. 

MOST LER, H. & RAHIMI-Y AZD, A. ( 1976): Ncue 
Holothuricnskleritc aus dem Oberpcrm von Julfa in 
Nordiran.- Geol. PaJaont. Mitt. Innsbruck, 5/7, 1-35. 

NEWELL, N. D. (1994): Is therc a prccisc Permian-Tri­
assic boundary?- Pennophi les, 24, 46-48. 

PAULL, R.K. & PAULL, R.A. (1 994): H indeodlls par­
vus - proposed index foss il for the Permian-Triassic 
boundary.- Lethaia, 27,27 1-272. 

PERCH-NIELSEN, K., BIRKENMAJER, K., BIRKE­
LUND, T. & AELLEN, M. (1974): Revision of Tri­
assic stratigraphy of the Scoresby Land and Jamc­
son Land region, east Grcenl and. - Gr0nlands geo!. 
Unders., Bull. , 109, I -51. 

POSENATO, R. (1 991 ): Endcmic to cosmopoli tan bra­
chiopods across the P(fr Boundary in the Southern 
Alps (It aly).- In : Proeeedings of Shall ow Tethys, 
Saito Ho-on Kai Special Publi cati on, 3, 125 -1 39, 
Sendai. 

RENN E, P.R. , ZHAN, Z., RICHARDS, M. A., BLA­
CK, M.T. & BAS U, A.R. (1995) : Synchrony and 



Kozur: Problems for Evaluation of the Scenario oflhe Pennian-Tri,lssic Boundary ... 

causal relations 'between Permian-Triassic boundary 
crises and S iberian flood volcanism.- Science, 269, 
1413- 1415. 

RIGBY, J.K. & GOSNEY, T.C. (1983): First reported 
Triassic lyssakid sponges from North America.- J. 
Paleonl. , 57/4, 787-796. 

SADOVNIKOV G.N. (1997): Taimyrian Stage of the 
terminal non-marine Permian. - In: PODEMSKI, M.; 
DYBOVA-JACHOWICZ, S., JAWOROWSKI, K. , 
JURECZKA, K. & WAGNER, R. (cds.): Proceed­
ings of the XIII Internat ional Congress on the Car­
boniferous and Permian. Prace panstw. Inst. Geol. , 
157,133- 136. 

SADOVNIKOV, G.N. & OR LOVA, E.F. (1993): The 
lower boundary and biostratigraphy o f the nonma­
rine Triassic in Siberia.- In: LUCAS, S.G. & MOR­
ALES, M. (eds.): The nonmarine Triassie. New Me­
xico Mus. Nal. Hisl. & Sci., Bull. , 3, 421-422. 

SADOVNIKOV, G.N. & ORLOVA, E.F. ( 1994): Tai­
myrian Stage - the terminal stage of the continental 
Permian.- Dok!. AN Russia, 338/5, 658-661 (in 
Russian). 

SEPKOSKI, J.J . (1997): Biodiversity: Past, present, and 
future.- J. Paleonl. , 71/4, 533-539. 

SO HN , I.G. (1970) : Early Triassic marine ostracodes 
from the Salt Range and Surghar Range, West Pak­
istan.- In : KUMMEL, B. & TEICHERT, C. (eds.): 
Stratigraphic boundary problems: Permian and Tri­
assic of Western Pak istan. Uni vers ity Press, 193-
206, Kansas. 

SWEET, W.c. (1976) : Conodonts from the Permian­
Tri assic boundary beds at Kap Stosch, East Green­
land.- Medd. Gr~n land, 197/5,51-54. 

TEICHERT, C. & KUMMEL, B. (1976): Permian-Tri­
assic boundary in the Kap Stosch area, East Green­
land.- Medd. Gr~nland, 197/5,3-49. 

TOZER, E.T. ( 1967): A standard for Triass ic time.­
Bull. Geol. Surv. Canada, 156, 1-103. 

TOZER, E.T. ( 1988): Defi nition of the Permian-Trias­
sic (P-T) boundary : The ques tion of the age of the 
OlOceras beds.- Mem. Soc. Geol. It., 34, 291-301. 

TUZHIKOVA, V.1. (1985): Miospory i strat igra fij a 
opornych razrezov triasa Urala. Nizhnij trias, pogra­
nichnaja verchnaja perm.- Akademia Nauk SSSR, 
Uralskij Nauchnij Centr, Sverdlovsk, 23 1 p. 

VISSHER, H. ( 1971): The Permian and Triassic of the 
Kingscourt outli er, Ireland. - Geo !. Surv. Ire land , 
Spec. paper, I , 114 p. 

WANG, c.Y. ( 1994): A conodont-based hi gh-resolu­
tion eventostratigraphy and biostratigraphy for the 
Permian-Triassic boundaries in South China.- Palac­
oworld, 4, 234-248. 

159 

WANG, C.Y. (1995a): Conodonts from the Permian­
Triass ic Boundary Beds and biostratigraphic bound­
ary in the Zhongxin Dad ui section at Meishan, 
Changx ing County, Zejiang Province, China.- Albe­
rtiana., 15, 13-19. 

WANG , c.Y. (1995b): Conodonts of the Permian-Tri ­
assic boundary beds and biostrat igraphic boundary. ­
Acta Palaeontologica Sinica, 34/2, 130-151. 

WANG, c.Y. (1995c): Upper Permian conodont stan ­
dard zonation.- Permophiles, 26, 20-23. 

WANG , C.Y. (1996): Conodont evolutionary lineage 
and zonation for the latest Pcnn ian and earliest Tri­
assic.- Permophiles, 29, 30-37. 

WANG, C.Y., KOZUR , H. , ISHIGA, H., KOTLYAR , 
G.V., RAMOVS, A., WANG Z.H. & ZAKHAROV, 
Y. (1996): Permian-Triassic boundary at Meishan of 
Changx ing County, Zhcj iang Province, China - A 
proposal on the global stratotype section and poin t 
(GSS P) for the base of the Triassic.- In: First Asian 
Conodont Symposium. Acta Micropaleonl. S inica, 
13/2, 109-124. 

WANG, c.y. & WANG, S.Q. (1997): Conodonts from 
Permian-Triassic boundary beds and evolutionary 
lineage of Hindeodus - Isarcicella .- Acta Palaeon to­
logica Sinica., 36/2, 15 1-169. 

WANG, K., GELDSETZER, H.H.J. & KROUSE, H.R. 
(1994): Permian-Triassic ex tinction : organic 813C 
evidence from British Columbia, Canada.- Geology, 
22, 580-584. 

WANG, Y., CHEN, c., RUI, L., WANG, Z., L1AO, Z. 
& HE, J. (1989): A potential global stratot ype of 
Permian-Triassic boundary.- Development in Geo­
science, Contribution to 28th International Geologi­
cal Congress, 1989, Washington D.C. USA, Science 
Press, 22 1-229, Beijing. 

WHATLEY, R. (1 995): Ostracoda and oceanic palaeo­
oxygen leve ls.- Mitl. hamb. zool. Mus. Insl. , 92 
(Ergbd.),337-353. 

WIGNALL, P.B. & HALLAM, A. (1992): Anoxia as a 
cause of the Pennianrrriassic mass extinction: faci ­
es ev idence from northern It aly and the western 
United States.- Palaeogeogr. , Palaeoclimal. , Palaeo­
ecol. , 93, 2 1-46. 

WIGNALL, P.B. & HALLAM, A. (1993): Griesbachi­
an (earliest Triassic) palaeoenvironmental changes 
in the Salt Range, Pakistan and southeast China and 
the ir bearing on the Permo-Triassic mass extinc­
ti on.- Palaeogeogr. , Palaeoclimato!., Palaeoeco l. , 
102,215-237. 

WIGNALL, P.B. & HALLAM, A. (1996): Facies cha­
nge and the end-Permi an mass ex tinct ion in S.E. 
Sichuan, China. - Palaios, 11 , 587-596. 

WIGNALL, P.B., HALLAM, A., LAI, X. & YANG, F. 
(1995): Palaeoenvironmental changes across the 



160 Geolog ia Croatica 5 [/2 

PLATE I 

Hilldeodus lalidenloills praeparvlIs KOZUR, x275, sample 68 KC 33, East Greenland, Lac. 2.1 after 
TEICHERT & KUMMEL (1976), corresponds about beds 8 and 9 in River 1 section after TEICHERT & 
KUMMEL (1976). This level is situated in the river 1 section 1-15 m above the last occurrence of Oloeeras, 
and Claraia occurs in the upper part of this level. Probably T. pascoei Zone. Lower part of H. parvus Zone. 

2 Hindeodus lafidenfafus praeparvus KOZUR with very large, but broad cusp, but denticulation similar to H. 
Iypicalis (SWEET), x92, sample 68 KC 33 (see Fig. I). 

3 Very primitive Hilldeodus parvus (KOZUR & PJATAKOVA), cusp still very broad as in H. latidentatlls 
praeparvus, but this is seemingly partly caused by fusion with the following denticle in the lower half of the 
cusp, transitional form to H. latidelltows praeparvlIs KOZUR, x92, sample 68 KC 33 (see Fig. I). 

4 Primitive Hindeodlls pm'vlls (KOZUR & PJATAKOVA), x92, sample 68 KC 33 (see Fig. 1). 

5 Hilldeodus latidelltatlls praeparvlIs KOZUR, x92, sample 68 KB 8 b, River I section after TEICHERT & 
KUMMEL (1976), 1-7 m above the last Otoceras, somewhat below the first occurrence of Claraia. Probably 
T. pascoei Zone. Basal part of H. parvus Zone. 

6 Transitional form between Hilldeodus parvlIs (KOZUR & PJATAKOVA) and H. latidelltaills praepa,-vus 
KOZUR, x92, sample 68 KB 8 b (see fig. 5). 

7 Very primitive Hilldeodlls parvlIs (KOZUR & PJATAKOVA), x92, sample 68 KB 16 B, River I section after 
TEICHERT & KUMMEL (1976), beds with Claraia, >30 m above the last Otoceras. Probably Ophieeras 
commune Zone. H. parVllS Zone. 

8 Hilldeodlls par VIIS anterodelltallls (DAI & ZHANG), x 128, sample 68 KC 42 A, East Greenland, Lac. 2.1 
after TEICHERT & KUMMEL (1976), 54 m above sample KC 33. Isareicella isarcica Zone. 

9 Hindeodlls lalidelllallls praeparvlIs KOZUR, x92, sample 63 TA- 122 (for sample position see SWEET, 1970), 
Pakistan, Chhidru West A, basal Kathwai Member, upper Dorashamian (uppermost Permian). 

10 Hilldeodlls lalidelllallls (KOZUR, MOSTLER & RAHIMI-Y AZD), x92, sample 63 TA-122 (see Fig. 9). 

11 Hilldcadus latidentatus praeparvus KOZUR, x92, sample 63 TA- 122 (sec Fig. 9), 

12 Hilldeodlls parvlIs (KOZUR& PJATAKOVA), x64, sample 63 K 3-5 (for sample position see SWEET, 1970), 
Pakistan, Chhidru West A, lower Kathwai Member, clay bed ca. 1.3 m above sample 63 TA-122. H. parvlts 
Zone of lowermost Triassic. 



Kozur PLATE! 161 



162 

Permian(Triassic boundary at Shangsi (N. Sichuan, 
China).- Hi storical Biology, 10, 175 -1 89. 

WIGNALL, P. B., KOZUR , H. & HALLAM, A. 
(1996) : On the tim ing of palaeoenvironmental 
changes at the Permo-Triassic (prrR) bo undary 
using conodOnl biostratigraphy.- Historical Biology, 
12,39-62. 

WIGNALL, P.B., MORANTE, R. & NEWTON, R. 
( J 998) : The Permo-Triassic trans ition in Spitsber­
gen: 813Corg chemostrat igraphy, Fe and S geochem­
istry, facies, fau na and trace foss ils.- Geo!. Mag., 
135/1,47-62. 

XIA, F. & ZHANG , B. ( 1992): Age of the Sc10ng G ro­
up, Selong of Xizang (Tibet) and the Permian-Trias­
sic boundary.- Joum. Strat., 16/4,256-263. 

YIN, H. (1985): On the transitional beds and the Pcrmi ­
an-Triassic boundary in South China.- News!. StraL, 
15/1, 13-27. 

YIN, H. (J 993) : A proposal for the g lobal stra lotype 
section and point (GSS P) of the Permian -Tri assic 
boundary.- Albertiana, 11,4-30. 

YIN, H., SWEET, W.e., GLENISTER, B.F., KOTL­
Y AR, G., KOZUR, R. , NEWELL, N.D., SHENG, 
J. , YANG, Z. & ZA KHAROV, Y.D. (I 996a): Reco­
mmendation or the Meishan section as Glob,\J Stra­
totype Section and Point for basal boundary of Tri­
assic System.- News!. Stratigr., 34/2, 8 1-1 08. 

YIN, H. , ZHANG , K. , WU , S. & PENG, Y. (l996b): 
Global correlation and definition of the Permian­
Triassic boundary.- In: YIN, I-I. (ed .): The Palaeo­
zoic- Mesozoic boundary. Candidates of global stra­
totype section and point of the Permian -Triassic 
boundary. China Univers ity of Geosc iences Press, 
3-28, Wuhan. 

YIN , 1-1. & Z HANG, K. (1996): Eventostratigraphy of 
the Permian-Triassic boundary at Mei shan section, 

Geologia Croat ica 51/2 

South Chi na. In : YIN, H. (ed. ): The Palaeozoic­
Mesozoic boundary. Cand idates of global stratotype 
section and point of the Permian-Triassic boundary. 
China Univers ity of Geoseienes Press, 84-96, Wu ­
han. 

ZAKHAROY, Yu.D., KOTLYAR , G.V. & OLEN 1-
KOY, A.V. (1995): Late Dorashamian (late Chang­
x ing ian) invertebrates of the Far East and Permi an 
to Triassic volcanism in the western Circumpacific.­
Geo!. Pac. Ocean, 12,47-60. 

ZA WIDZKA, K. (1971 ): A polychae te jaw appara tus 
and some seoleeodonts from the Pol ish Middle Tri­
ass ie.- Actageo!. Polonica, 2 1/3, 36 1-377. 

Z HANG, K. , DING , M. , LA I, X. & Ll U, 1. ( 1996): 
Conodont sequences of the Permian-Triassic bound­
ary strata at Mei shan sectio n, South Chi na. - In: 
YIN, I-I. (ed.): The Palaeozo ic-Mesozoic boundary. 
Candidates of global stratotype section and point of 
the Permian-Triassic boundary. China University of 
Geosciencs Press, 57-64, Wuhan. 

Z HANG, K., LAI, X., DING , M. & LlU, J. (1995 ): 
Conodont sequence and it s g lobal correlati on of 
Permian-Tri assic boundary in Meishan sect ion , 
Changx ing, Zhejiang Provin ce.- Earth Science, 
Journal of Ch ina University of Geosc iences, 20/6, 
669-676. 

Z HU, X. & LIN, L. (1997): Typical Hindeodus parvus 
and it s s ig nificance and discussion on P{f bound­
ary.- Joum. Jiangxi Normal Univ., 21/1 , 88-95. 

ZHU, X.S., WANG, C.Y., LU, 1-1. , MU, X.N. , ZHANG, 
L.X. , QIN, Z.S., LUO, I-I. , YANG , W.R. & DENG , 
Z.Q. ( 1994): Permian-Tri ass ic boundaries in Jiang­
x i, China.- Acta Micropa laeonl. Sinica, 11 /4,439-
453. 

Manuscript received June 25 , 1998. 
Rev ised manuscript accepted November 23, L998.