Rivist;r italian;r di Paleontologra e Stratisrafia Key uords; Anornoepus ichnogenus, Lower Jurassic, Hettan- girn, Sinenrurian, l-avini di Marco tracksite. RiassLnúo. 11 sito p;rleontologico dci Lavini di M:rrco, presso Rovereto (Trcnto) riìppresenta un yasto tida/ flat fossile di età Giur;ls- sico infcriore (Formezione dci Calcari Grigi Membro jnferiore; Het- t:rngiano - Sinemuriano inf.). Un larso insieme di improntc riferibili a dìnos;ruri, vi ò steto scoperto pochi anni fa cd esso è attualmente oggetto di estensivi studi icnologici e paleobiologici. Lc inrpronte oggetto di questa nota sono riferibili al piede dcstro e sinistro di un medesimo individuo posti jn posiz-ionc affiancat:r e subparallela in ur.r attessiarnento di erresto e accucciamcnto. Le orme sono attribuibili ad Attometepus Hitchcock 1848. Tra le orme finora docunrentrte le mrg- giori effinìtà corrispondono t Moyenisauropus tlodai Ellenbcrger 197'1 (.recte Anontoepus detdai Olsen & Gelton 198'1) del Lcsotho mentre diffenscono dalle forme attribujte ad Anontoepus identificate nell'emi- sfero settentrionale. Questo potrebbe confcrnr.rre la p:rcntcla gond- wanica per l'icnofeuna clì Rovereto già supposta nello studio di altri titxf,. Abstract. The palaeontologic site at Lavini di Ìúarco, near to Rovereto (Trento), reveals a wjde fossil tidal flat of Early Jur:rssic :rge (Calcarì Grigi Formations - lorver Member; He ttangiln to lol.er Sjne- murian ). An extensive sct of dinosaur prints were discovered a few vears ago and are non the subject of ichnologrcal and paleobiological stucljes. The prints rvhich arc dcscribed ìn present short note are believed to represent the right and Ìett foot of thc same individual, set in a side-by-side, sub-parallel, sirting posrur.. Thc prints can be clas- sified. as AnomoepLts Hitchcock 1848. Ar-nongst recogniscd ich- nospecies, most of thc chrrrchterìsric' of the prints here describecl poìnt to ùloyenìsauropus tÌodai Elenberger 1974 (recte Artotnoepus dodai Olsen & Gelton 198a) oi l.esotho. 81' contr:rst, the prints found rt Lavini dì Marco diffcr {rom the Anornoepus for-rnd in the Northcrn Emisphere. These characters would seem to confirm the Gonclr.anic origìns of the Rovcreto ichnofauna as previouslr- sup- posed from thc studl- of other tax:r. lntroduction. The Lower Jurassic tracksite at Lavini di Marco, near Ro\rcreto (Northern Italy) is a large , fossil tidal flat Aprile 2001 (Lanzinger & Leonardi 7992; Leonardi & Lanzinger 1992;Leonardi & Avanzini 1994; Avanzini er ^1.1997). The dinosaur footprints were discovered a few years ago and have been the subiect of extensive ichnological and paleobiological studies (Lanzinger & Leonardi 1992; Leonardi Ec Avanzini 1994; Dalla Vecchia 1994; Leonar- di Ec Mietto in press). The paleoenvironment at Lavini di Marco, as deduced from sedimentology and geochemistry, is a rel- atively arid coastal zone lacking perennial freshwater reservoirs (Avanzini et à1. 1997). There is evidence of fluctuations in vegetation density and difference o\rer time documented by the occurrence of paiynomorphs, among them Corollina sp. and Porcellispora sp., (Avanzi- nl et al. luuu). Regional scale stratigraphic and sedimentological characteristics allow reconstruction of the Early Jurassic settinF, of a coastal environment that probably stretched southwàrds. The coastal belt was à tongue of tidal flats lTrento Platform). bordered to the west and to the east by basins developed as a consequence of the foundering of the Lombardy Basin to the west and the Belluno tough to the east. Trackways and footprints nost commonly occur on six layers within one inter-to supratidal interval char- ecterized by vlriable lateral thickncss and facies (Lower Member of Calcari Grigi Formation, Hettxngian to Lower Sinen-rurian in age). Detailed studies of the tracks are ongoing. With the present state of knowledge. tri- dactyl footprints are represented by theropod of Gralla- tor Hitchcock, 1858 and Ewbrontr:s Hitchcock, 1845 ich- notaxa. Other tracks are attributed to primitive sauropods (Parabrontopodus Lock\ey, Farlow & Meyer, 1994 and Breztiparopus Dutuit & Ouazzou, 1980, ichno- NOTA BREVE - SHORT NOTF FIRST REPORT OF SITTING ANOMOEPUS TRACKS IN EUROPEAN LO\íER JURASSIC (LAVINI DI MARCO SITE - NORTHERN ITALY) MARCO AVANZINI'i, GERARD GIERLINSKI':'!E{ GIUSEPPE LEONARDI)t':r'' Recei.':ed Scprember 23, 2Aa0: acceptetl January 1 5, 2AAl 'i Museo Tridentino di Scienze Naturalì, r.ia Calcpìna 1'+, 38100 Trento, Itaìv - avanzini(rr-ìmtsn.tn.it ':': Panstwory Instvtut Geologicznr'-, ul. Rakon'iecka '+, PL 00-9/5 -Warszawa, Poland )ijiji Museo Trìclentino di Scienze Nrturali, via Calepina 14, 18100 Trento, Italy; present address: via Modiglìani 2,E00/0 lv{onterusciello 1\A7. Irr'r gi.leorrrJi,,ìibcro.ir t32 M. Artanzinì, G. Gierlinski & G. Leonardi genera) and small ornithischian dinosaurs (Leonardi & Mietto, in press). This association is similar ro orhers found in the Lower Li.rssic. Systematic lchnology. The footprinrs rhat are the subject of the present report are imprinted on the surface of stromatolitic bindstone level (layer 106). This layer was dolomitized in the earll' stages of diagenesis under semi-arid climatic conditions, where evaporation exeeded precipitation. In particular the trampled layer was characterized by a suc- cession of plastic semiliquid mud and partially lithified sediments, capped by elastic cyanobacterial laminites (Avanzini 1998). The footprints are poorly preserved, as commonly occurs for footprints impressed in carbonate sediments. Poor prese rvation is also due to karst corro- sion of the surface. Order Ornithischia Seeley, 1888 Ichnofamily Anomoepodida Lull, tSO+ Ichnogenus Anomoepus Hitchock, 1848 Description. The prints belong to the right :rnd lcft foot of the same individual, and are arranged in a side by side, and diverging slightly distally. Unfortunately the left footprint is partly eroded, but three digit impres- sions and the outline of the heei are visibie. The right footprint, which is better preserved, is clearly trid.rctl-Ì, and there is marked elongation close to the axis of the third digit, which can be interpreted as the impression of the metatarsal area (Fig. 1). Pes: tridactyl with digits II-IV impressed. Low val- ues of projection of digit III beyond II and IV(2.5 cm). rÌ'Ihe pes is longer thrn wide. Digit IV is longest. Footprint length, 12.3 cm; with the metapodium, 24.9 cm. Footprint width, 1 1.i cm. Divarication of digits II-III, 34'; III-I! 23"; II- IV 55'. Ler-igth of digit II,7.5 cm; of III, 9.5 cm; of I! 10.0 cm. Phalangeal pads are not well defined. Metatarsal- phalangeal pads of digits III and IV made rwo isolated posterior impressions. On the distal end of digits are preserved impressions of stumpy and rounded claws. The metapodium print js 12.6 cm in length and 4.5 cnr in width. The proximal end shows a marked asymmerry with the lateral part being larger than the medial. Manus; Close to the right foot, the impression of three parallel furrows set in front of an elongated depres- sion can be recognised and in a cenrral position between the rear limbs there is another print in which two proba- ble short, and robust digits are visible. These incomplete prints are ,1.5-5 cm long and 4-5 cm wide. It ls not corrì- pletely clear whether or not these tracks can be attrib- uted to the front limbs. However, some of these (i.e. the central print) show characteristics which indicate that the prints may have been left by the hands, when the sub- ject was exploring the ground before stopping. Comparison. The size and general morphology of these foot- prints assign thern to ichnotaxon,4nomoepus Hitchcock, 1848. The n-rain features of ichnogenus Anomoepus àrei broad pes with toes tending to be broadly splayed (divarication II-IV - ZO'), relatively large width of dig- its, lon' values of projection of digit III beyond the other toes, digit II, III and IV subequal in length but the pedal digit IV is always slightly longer than others (Olsen & Galton 1984; Demathieu 1990; Thulborn 1990; Farlow & Lockle;. 1993). The manus impression r'hen present, has four or five subequal toes.and is sometimes rot:lred outrvards (Olsen & Galton 1984). Anomoepus trackwàys are usually bipedal. Some tracks shows that the animal sometimes switched from bipedal to quadrupedal pro- gression and even ro a stationarv crouching position. In resting tracks all four feet, along with the metatarsal and sometimes the rschiadic callositv and the belly x1. impressed. The size of the feet, the relative length of the dig- its and the metatarsal lengths of the specimen described, are similar those of some African specimens as i.e. Moyenisauropus dodai Ellenberge r 1.974 (recte Anomoe, pus dodai Olsen 8r G:rlton, 1984) : L:14 cm, 24cm with heel, \f = 05-115 cm, digit I (non functional), digit II : Z.O (with metatarsal-phalangeal pad : 1O cm), digit III : 9 cm (u.ith rnetatarsal-ph:rlangeal pad :1O.5cm), IV: 10 cm. Projection of digit III: 4.5 cm (Ellenbcrgcr 1971).The total angle of divarication II-IV is similar to that described by Ellenberger (1 971) for the typc of this ichnospecies; in track 70", in resting pose 55", (II-III, 30', III-IV 4O') . Typical North American rnaterial dif- fers from our specimen in having shorter digits end gen- Fig l -Anomoepussp.{ootprintsatLavinidiMarcorcvealevidenceofcrouching(A).Specificallvnotethemetatiìrsal printsarranecdinaside b1' side, and dìverging slightly distallv (B). The right footprint (D), shows the main features of ichnogcnus,4 nontoepus: broad pcs *,ith digit lI' III and IV subequal in length and broadll'splaved, relativclv large r-idth of digits end iowvalues ofprojection of.1;gi, rtt beyond the other toes. IntcrPretetive drawing shows other prints on the same surface (C). Somc of tL.r. r.r-,,"t h".-. b.", left ùy the hands. Scale bar : 10 cm. S ittìng Anomoepus tracÌes ùa: i' | .r / ,--\-\cd,é ) i .-l iaIJ"C '.--l \ \/ \ t'1.-J' ,.1 lz\ / t --/ \j \ i-j\J' ' ,\,Y I\J ... ,'{,r ._r_ \ \'-ll.. tu I'- t,,, c; O , -,.-...(] ? i_ \\{ * \!\:\.. ..1J 131 M. Avanzini, G. Gíerlinslei €: G. Leonardi Fig. 2 - Ncrv spccimen of Anontoepus pìenleot-skii Gicrljnski, 1991 (Nluz. PIG 1662.1L1) from the Hettansian of Gili;rnr- Las (Poland), which q'as ìeft during a plantier;rde gait. Scale b:rr -5cm. erally smaller dimensions, but divarication angles II-III and III-IV are sin'rilar ro rhose of Anomoepus scambus Hitchock, 18,+8 (35',23'). Among the Northern Hemi- sphere anomoepodicls, the most similar form is Anomoe- pus pienkow,s,èii Gierlinski, 1991from the Lower Jurassic of Poland. FIowever, Polish Anomoepus rracks have a more robust ge neral structure u.ith the shorter metatarsal imprints, which appared in the new discov- ered specimen Muz. PIG 1662.II.t (Fig. 2). Discussion. Anomoepus is a distìnctive classic Earlv Jurassic track type first reported from the Connecticut Valley (Hitchcock 1848; Lull 19a4, D53; Olsen 1980a; Olsen & Galton 1984) but now also known from Europe, Africa and Australia (Olsen & Galton 1984; Thulborn 1994; Lockley 8c Hunt 1995; Lockley 8c Meyer 2OOO). The Early Jurassic assemblage from the Newark Supergroup and Glen Canyon Group of North America is predominantly composed of Late Triassic survivors (mainly large sized Grallator, and exrremely. rare Rhyn- cbosauroides), with the addition of AnomctEzzs (Welles 1921; Olsen 1978, 1980 a-c; Clark & Fastovsky 1986; Olsen & Padian 1986; Olsen Ec Baird 1986, Silvestri 1ee6). The ichnoge n:us Anomoepzs is an abundant ichnite in the Lower Jurassic Stormberg Group of Lesot}ro (Ellenberger 1972,1971; Olsen Er Galton 1984; Colbert 1986; Haubold 1986) and Early Jurassic prints, attrib- uted to small ornithischian dinosaurs (Anomoepus gracil lintus) have been reported in the Carnarvon Gorge, Quecnsland (Thulborn 1994). Anomoepus is :rlso present in Central Europe. The Polish ichnofauna described by Gierlinski (1991, 1994, 1995, 1,996a-b, 1.997), Gierlinski & Sawicki (1998) and Gierlinski & Pienkowski (1999), comes from the norrh- ern slopes of the Holv Cross Mountain, located about 150 km sourh of \fars:rvi from the Zagtje Formation, Skoloy Formation and Przl,sucha Ore-Bearing Form;- tìon. Floristìc remains and sequencc strarigraphy corre- lation indicate a Hettangian age of all these formations. Thel' represcnr various continental and marginal-marine environmenrs. Fluvial and lacustrine scdiments domi- nate in the contincnt:rl Los'er Ztga,je Form:rtion, n,hile the ncarshore and deltaic facies arc present in the Sholoy Formation, Uppcr Zagale Formation and Przl-such.r Orc-Bearing Formation. Various ornithischi;rn) s.ìuro- pod and the ropod rracks occur in these sediments (Gicr- Ìir-rski Er Pienkon'ski 1999; Lockley Et Meyer 2OOO). The presence of early ornitischians in Europe of is particu- larll' significant ro inrerpretation of the Lavini di Marco ichnoassociation. Gierlinski (1991, 1999) contends that the Polish ichnospecies of Anomoepus pienkctvsleiì differs fron'r the classic Connecticut forms in beine lrrger .rnd having a larger manlÌs print. However, Anomoepus pienko.usleii, Gierlinski, 1991, differs also from thc prints described in this reporr. Taking inro accounr the distribution of Anomoe- pus, and considering the concept that Early Jur:lssic fau- nas are cosmopolitan (Hunt et al. 1996), it is interesting to note that the Anc.tmoepus obse rved at Lavini di Marco is the most similar to the forms documented in Lesotho, slightly different from thc Polish specimens and subs- tiantialiy distinctive among the other Northern Hemi- sphere anomoepodids. This fact could suggest that the ichnofauna of Rovereto may have Gondwaniln origins, as previously postulated by Leonardi and Mietto (in press) from the study of other taxa. It is also note$/or- thy that the Hettangian tracks of Poland, robust anomoepodids and sauropod tracks (Gierlinski 1992; Gierlinski & Pienkowski 1999; Gierlinski & Sawichi 1998), remain stronger similarities ro rhe distinctive Italian assemblage than to other Laurasian ichnofaunas. Ackno.o/edgements. \We are very srateful to J. O. Farloq H. Frey and H. G. Lock- ley for the scientific and linguistic revision of the manuscript and usc- ful suggestions thar have improved substantially this paper. 1: Sitting Anomoepus tracks RE,FERE,NCES r35 Avanzini M. (199S) - Anatomy of a Footprint. Bioturbation as a key to r.rnterstand dinosaur walk dynamics. Ichnos, 6 (3): 129-139, Chur, New York. 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