ltaliana di Paleontologia e Stratigrafia NOTA BREVE - SHORT NOTE DITRUPA BREYIS N. NEOGENE \TITH SP., A NE\T SERPULID COMMENTS ON THE FROM THE MEDITERRANEAN ECOLOGY OF THE GENUS ROSSANA SANFILIPPO Received April 24, 1999; accepted October 24, 1999 Key u,ords: Ditrupa, new species, Neogene, southern Italy, bio- mer.-. -i"r^"r"""r".o Riasswnto. Viene descritta la nuova specje Ditrupa brnis (Poly- chaera, Serpulidae) riscontrata in sedimenri siltosi del Pliocene medio di Tufara (Italia meridionale). D. br*-ìs è stata anche segnalara per il Miocene superiore della Calabria. Il paleoambiente, in base alle faune associate, corrisponderebbe ad un fondale infralitorale o circalitorale suPeriore. Rispetto t D. arietina la specie ha un tubo piìr piccolo, meno affusolato verso I'apice e presenta frecluenti inspessirnenri circolari della parete ("annuli") in prossimità dell'apertura. Osseruazioni al microscopio elettronico a scansione su fratture trasversali del tubo hanno evidenziato una microstruttura, comune anclre al genere, caretterizz.ttt dalla presenza di due strati: uno esrerno trasparente con grossr cristalli isoorientati ortogona.Lmente al tubo, ed uno interno bianco opaco, più sottile, con cristalli prisnatici di piccole Jirncn:ioni, .ì strutturx incrocirtr. I tubi di Ditrupa cosrituiscono il subsrrato per numerosi orgr- nisn-ri epifaunali; la loro elevata densità. rn un fondale può influenzare composizione e diversità delle comunità di fondo mobile associate. Sono ipotizzrre differenti posizioni di vita di Ditrupa rn rap- porto al substrato, dovuti alla sua capacità di risposta alla dinamica del fondo r-nobile in cui vive. Abstract. The new species Ditupa brnis (Pol1,chaeta, Serpuli- dae) is described from Middle Pliocene silts of southern Italy. It is also reported from Upper Miocene sediments of southern Italy. The asso- ciated faunas sugg,est an infralittoral or upper-circalittoral distribution. A r-norphometrical and microstructural analysis of tube was carried out. D. brnis closely resembles Ditrupa arietina brt severzl norphometrical differences allow ro discriminate the two specres. The Ditrwpa tubes provide a substrate for a diversified epifau- na. 'l'heir high density grearly affecrs species composition and diversr- tv Òf soft-bottorn cornmunitie'. It is concluded tht Di*upa can live in various positions with respect to the sediment surface, depending on local sedimenrxrion rare and dynamics. lntroduction. Ditrupa Berkeley, 1835 is the only serpulid genus characterised by an unattached tusk-shaped rube. It has a long history of taxonomic confusion, early descrip- tions being poor, ofren based on empry tubes, which are rather featureless. This often led to rnisidenti[y Ditrupa as scaphopod rnolluscs and vice versa. Ditupa has been associared with many serpulid genera in identification keys (Placostegws, Vermiliopsis s.1., Bonhowrella, Sclerostyla, Dasynema and Marfugia) but it really seems to ser srell apart sysrematically. In some cases, even the genus has been misinterpreted. In the palaeontological literature rhe raxonomic confusion has been greaferi represenratives of rhe genus Di*upa often were placed erroneously wirh other serpulids and vice versa. An example is given by the serpulid Serpula libera Sars, 1835 later placed into the synonymy of D. arietina. Ditrupa is known since the Tertiary: Paleocene- Eocene of Spain (Gaemers, 1978), Miocene of Taiwan and Australia (Cheng, 1,974; ten Hove & Smith, 1990). It is common in Mediterranean Plio-Pleistocene sedi- ments. Ditrwpa arietina O. F. Miiller, 7776 occurs in the eastern Atiantic (f rom Iceland to Azores, Canary Islands and Senegal) and the Mediterranean. Ten Flove & Smith (1990) re-described a distinct species, Ditrupa gracillima Grube, 1828, from the Indo-Pacific and on this occasion gave a rhorough review on Ditrupa taxon- omy, morphology and ecology. F{ere, a new species ol Ditrwpa from the Neogene of southern Italy is described. Materials and methods. The examined material of the new species Ditrupa brez,is originates f rom Miocene and Pliocene silty deposits, in southern Italy: - Diparrimento di Scienze Geologiche, Sezione di Oceanologia e Paleoecologia, Università di Catania - Corso Italir 55, 95129 Cetenir e-rrrril:'.rnIiror@mbox.unict.it 456 315 R. Sanfilippo Fig. 1 - Location of Tufara and Ben- e\t.lre section:. Arrons point lavers containingto D. brnìs. BENESTARE Some populations of gypstrrÌ :;;..",,. Ditrupa drietina lronr Pliocene.sands Pleistocene and Recent sedi- menrs, were also studied: M I D D L- E P L I o C E N E m0 Tufara. This section is ca. 300 m thick and crops out along the eastern edge of the Caudina Valley, S\l of Benevento (Fig. 1). It consists of alternating ciayey silts and sands Middle Pliocene in age (MPL5 Zone) (De Casrro Coppa et al., 1969; Violanri, unpubl. data). Fau- nas testify an upper-circalittoral palaeoenvironmenr in the basal part of the section, evolving to infralittoral upwards (Barbera et al., 1995). Near the contact with the sandy levels, some silty layers with Corbwla gibba and Ditrwpa breais occur, corresponding to the present-day Heterogeneous Communities. These layers contain species of different biocoenoses and are characterised by quasi-permanent instabiiity of qualitative and quantita- tive faunal composition (Picard, 1965). The type materi- al of the new species is from these silty beds. The tubes are often broken (more than 1,000 tube fragments). Benestare. This secrion is located ca. 1 km NV of Benestare (Fig. 1). It is a classic locality, originally reported on by Seguenza (1879-80) Late Miocene and probably Tortonian in age. The sequence is made of clays, 100 m thick, with silty-sandy layers on its upper part and a fossiliferous level of siliceous sands and Messinian gypsum. Ditrwpa brevis comes from two silty layers (Ben- estare I and Benestare II) at the top of the clayey bed. Fragmented tubes largely prevail. Samples also contain abundant Corbula gibba and lunulitiform bryozoans, indicating Heterogeneous Communities (Di Geronimo et al.. 1.992\. sjlty sands clays Diolo. Along the Stra- monte River in Vestern Emilia, northern ltaly. Material comes from .r silty-sendy layer 2 m rhick, wirhin a clayey-silty sequence of Middle Pliocene age. It contains circalittoral fau- nas referable to a Coastal Detri- tic Assemblage (Di Geronimo et al., 1992). The presence of sedinrentary insrability indica- tors among molluscs and l:ryozoans, rogether with the dominance of Corbwla gibba and D. arìetina, suggesrs an incipient rurbidity (see Di Geronimo & Robba, 1989). lonian Sea dredges. Gulf of Noto (off SE Sicily): Stn. PS/S1 5B (- 47 m),36"52.98'N, 15'10.48'E; Stn. PS/81 5C (- 34 m), 36'53.30' N, 15'09.82' E. Srmples consist of biogenic sands containing faunas referable ro the Coastal Detritic Assemblage. Catania Gulf dredges, Stn. CT/11 (-110 m), 3Z'29.15'N, 15'09.05'8. Sandy gravels containing wùr- mian faunas (Di Geronimo & Li Gioi, 1980) including several tubes of D. arietina; Acitrezza, Srn. AC/50 (- 50 m) dredged ca. 1 km off the coasrline. Volcanic sands containing circalittoral faunas referable to a Coastal Detritic Assemblage swept by bottom currenrs. Tyrrhenian Sea dredges. Off Patti, Stn. PD4 (- 50 m), 38'09.40'N, 15"02.19'E. Muddy sands with faunas belonging to the Coastai Detritic Assernblage subject to an incipient turbidity. Measurements were taken from Recent and fossil specimens of Ditrupa, mainly following the method pro- posed by ten Hove & Smith (1990) (Fig. 2). Only whole tubes were measured. Values and standard deviation of each morphome- tric character have been compiled (Tab. 1). Pearson cor- relation coefficients between data were cluster analysed (Figs. 3, 4), using the average linkage method (Sokal & Sneath, 1963; Sneath sc Sokal, tlzl;. PLATE 1 Scale bar = Fig. 1-3: 0.6 mm; Fig. 4: 150 prn; Fig. 5, /, 8: 1 mm; Fig. 6: 200 pm; Fig. 9: 3 mm. Fig. 1,) Ditrupa breois,holotype (on the right) and parat)'pes. Tufara, Middle Pliocene. Fig.2) Ditrupa 1zre,--2.s. Benestare, Miocene. Ì.-ig. 3) Small- sized Ditrupa arietina. PS/81 58, Recent. Fig. 4) Apex of D. brnis. The rirn consists only of the outer hyaline layer. Tufara, Middle Pliocene. Ii5. 5) D. arietina. Diolo, Middle Pliocene. Fig.6) D. arietina. PS/81 5C, Recent. Fig. 7) D. arietina. PD 4, Recent. Fig. 8) Large D. arietina. CT/1.1, Wùrmian. Fig. 9) D. arietina wìth Hydroides norvegicus coiling around the anterior ends of rubes. CTl11, Wirrmian. Pl. 1 A new serpulid from Mediterrdnedn Neogene 457 458 R. Sanfilippo Chord (m!) Height mean D. D. mouth D. apex Arcuation (mm) (%) 0-4.48-8 (sD : 1.8) .02-0.1 3-0.50 0.29-0.60-0.95 0.34-0.53-0.75 0.28-0.37-0.56 1-2.A2-7 (sD = 0.11) r (sD = 0.15) (SD = 0.11) (SD = 0.07) (SD = 1.58) Tufara 10 Benestarel 2.70-4.68-9'80 (sD = 1 63) 2.60-3.'t 6-3.80 0.05-0.1 1-0.20 0.40-0.55-0.75 0.40-0.49-0.58 0.30-0.36-0.44 1 .70-3.26-5.20 nIn t^^ àriaiinà cT/1 1 .199 , 0.55-0.79- 1 .1 0 I (SD = 0.14) i (SD : 0.1!L ' o.oo-0.64-1 .50 (sD = 0.27) , t?i.?strs 0.45-0.65-0.85 0.25-0.79j1 .40 0.30-0.71-1 .70 = o.24) 0.23-O.47-0.68 0.30-o.70-0.80 (sp = 0.1) 0.30-0.73-1 .20 (sD = 0.16) (sD : o.oe) (sD : 2.49) 0.21-0.34-0.38 3.2-4.21-13 €D=005) 1SD=235) 0.20-0.36-0.57 3-6.01-14 (sD=013) (SD=1.2) o.À-o.zo-r 7.so1s-22.s1 , 0.32-O.63-0.97 (SD = 7.1e) (SD = 1.a6) (sD = 0.42) r (SP : o.l1 (sD = 0 71) 0.30-0.62-1 .30 0.20-0.36-0.70 10-10.69-15.13 =n21\ 0.5-1 .59-2 (sD = 0.38) (sD=021) (SD=2.83) 5.50-24.01-40 0.8-3.73-7 PS/81 58 2.90-4.80-10.80 j 0.10-0.32-1 .30 2.60-8.Os-'t6 0.10-0.s1-2.30 88 i (S?= 0.291 1 (Sq - !.1!L Diof o 2 ", 2.70-6.24-21 .10 0.27-0.71-9.10 72 (SD = 3.23) (SD = 0. Tab. 1 - Morphometric parameters measured on tubes of D. brnis and D. arietina populations. For each semple rmximum, nrinimum, rne rn val- ues (bold) and standard deviation are reported. The total number of measured tubes for each sample is reported on the left. Systematics. Genus Ditrupa Berkeley, 1835 Ditrupa brevis sp. nov. (Pl. 1, Figs. L-9 PL.2, Figs. 1-5) Derivatio nominis: from latin brevis (= 5[611; Type material deposited in the Palaeontological Museum of the Catania University, collections of the Departn-rent of Geological Sci- ence. Labelled PMC.S1.20-10-99. Description. Tube nor encrusting. circular in cross-section, scarcely bent and smal1 (mean length 4 mm, mean diam- eter 0.6 mm). Tube opened at both ends, slightly rr^r- rowing to apex (almost cylindrical). Mean diameter at mouth 0.5 mm, diameter of apex ranging from 0.3 to 0.5 mm. Just before mouth, tube narrows forming conical shoulder. Rim of both mouth and apex circular and smooth. Distal ends often with irregularly spaced annu- lar thickenings ("annu1i" sensu ten Hove & Smith, 1990) (Fig. 5; Pl. 1, Fig. 1). Outer tube surface smooth, except for occasional transversal lines and/or constrictions mainly near the mouth. Holotype: (PMC.S1.20-10-1999) length 3.2 mm, diameter of apex 0.4 mm, diameter ar mouth 0.5 mm. Miorostructure. Transverse fractures of the wal1 show two layers (Pl. 2, Fig. 3): an inner white one, thick ca. 1/4 of the entire wall and an outer somewhat transparent one rhicker just before mouth, showing still some trans- parency despite fossilisation. Under SEM magnification the outer hyaline layer is composed of needle-like crys- tals arranged in lamellae, perpendicular to the tube sur- face. The inner opaque layer shows small prismatic crys- tals, crossiy arranged. The apex is made only of the outer hyaline layer, the inner opaque layer starting at some dis- tance from the apex (Pl. 1, Fig. 4). At higher magnifica- tions, the outer surface does no longer appear smooth but is faintly dotted, due to the tips of crystals perpen- dicular to the surface (Pl. 2, Fig. 5). A discontinuous thin layer with an amorphous cryptocrystalline structure is randomlv Dresent on the outer surface. PLATE 2 Scale bar: Fig. 1: 200 pm; Figs.2,4: 100 pm; Fig.3: 40 pm; Fig.5:4 pLm. Fig. I) Ditrupa breris; a) anterior end; b) detail of a transversal line corresponding to a beginning of the tube growth. Tufara, Middìe Pliocene. Fig. 3) Ditrupa bretis, rra.nsverse section of the tube wall showing an inner opaque layer with criss-cross arranged crystals and an outer glossy layer, q.ith needle-like crystaÌs, perpendicular to the outer surface. Benestare, Miocene. Fig. 2) D. arietinawith a cylindrical bore-hole by a rnuricid ges- rropod. Mecanical abrasion trrÌces are visible on the outer surface. PS/81 5C, Recent. Fig. 4) Bore-hole due to a naticid gastropod wrth bevelled edge. D. arietina. PS/81 5C, Recent. Fig. 5) Detail of the outer surface of D. brnis, fa.intly dotted. Tufara, Middle Pliocene. 459Pl. 2 A new serpulid from MediterrLrnedn Neogene +60 R. Sanfilippo Biometry. The measured tubes of Ditrupa are easily classed in two groups (Tab. 1): in the first group (D. breais: samples Tufara, Benestare I and Benestare II) tubes have notably low mean values of chord (3.t0 - 4.68 mm) and height (0.11 - 0.22 mm); in the second group (D. arieri- na.'samples AC/50, PD 4, PS/81 5B, PS/81 5C, Diolo 2, CT/1,1) tubes have mean values of chord of +.so - 24.01 mm and of heighr of 0.32 - 3.73 mm. In the first group apices show mean diameters (0.36 - 0.38 mm) similar to those of the second group, despite in the latter the tubes are generally much larger in size (Tab. 1) . In both species the apex evidently remains unchanged from juvenile to adult stage (as showed also by the low values of SD). Even between specimens of D. arietinahaving different sizes, the apex diameter seems to be the only parameter morphometrically unchanged, tube accretion being pos- sible only at the mouth. The mean values of the arcuation index 2.82 - 4.48% also differ in the first group, versus 4.21 - l5'h in the second group (Tab. 1). Arcuation varies considerably within a population, ranging from almost straight (juveniles) to stròngly curved (adults). It may also vary between populations from different sites. For instance, in the D. arietina pop- ulation from the Gulf of Catania (Pl. 1, Figs. 8, 9) the arcuation index is greater than in other Recent popula- tions here examined (PS/81 58 and 5C) (Pl. 1, Figs.3,5, 6, 7). The other examined size-shape parameters of Ditrupa also increase notably with growth and can vary considerably between different Recent and fossil popu- lations. The differences between the two species are also shown by cluster analysis (Fig. 3) where samples of D. breztis (Benestare I, Benestare II and Tufara) are grouped rogerher. SD values (Tab. 1) of the two species are nor markedly different. Remarks. D. breois tube is much shorter than those of the other two Ditrupa species. Compared rc D. arietina and D. gracillima, tube of the new species is aiso scarcely bent and almost cylindrical, slightly narrowing to the apex. Both D. arietina and D. brevis show transversal lines and consrrictions on the outer surface, mainly near the opening (Pl. 1, Fig. 8; PI.2, Fig. 1). These are due to a thinning of the external wall layer, as occurring at the mouth rim, and were interpreted by Gambi (1986) as markers of previous tube openings. Conversely, the so- called "annuli", described for Ditrwpa arietina and D. gracillima by ten Hove & Smith (1990) as irregularities in the tube wall thickness, may occur in D. breois (PI. 1., Fìg.2 - Morphometrics of D. brnis trbe. D=diameter of tube n-routh, d:diameter of lpex, rlD=mean wrdth, c:chord (length measured in straight line betr.een orifice ro rpex), h:height (wiclest perpendicular disrance between rnner cur-ve of tube and chord). Fig. 1). However, these "annuli" are more frequent and elevated than in D. arietina but less abrupt than in the "monilifera" form of D. gracillima. A Ditrwpa tube resembles a scaphopod shell, par- ticularly the curved and smooth shell of Gadila. How- ever, microstructural analysis reveals a distinctive two- layered pattern ol Ditrupa tube (P1. 2,Fig.3): an outer layer somewhat transparent (which may become opaque by abrasion or fossilisation), and an inner bright white layer, of more randomly arranged crystals (ten Hove & Zibrowius, 1986;Ziltrowius Er ten FIove, 1982). The dis- tinction between the. two layers is generally evident, although in fossils the tube is entirely opaque, due to recrys tallisation. The outer tube surface is also peculiar. At higher magnification, the seemingly smooth surface can appear faintly dotted (P1.2, Fig. 5), similar to the fine honey- comb structure described by ten Hove & Smith 1t9lo; for D. gracillima, bv. less pronounced. Ecology and dlstribution. Ditrupa lives with its tube free on muddy sedi- ments on the continental sheif, in areas with high sedi- PS/81 58 PS/81 5C PD4 AC/50 Diolo 2 CT/l1 Tulara Benestare 2 Benestare 1 mentation rate and a quasi-permanent turbidity. In such environmental conditions, populations can be very dense (Di Geronimo et a1., 1989) and tubes ofren con- stitute a conspicuous component (over 5O%) of the bio- genic carbonate sediments (Vilson, 1976).It also occurs in circalittoral detritic bottoms with scarce muddy com- ponent, although never abundanr. Empty rubes, after the death of the animal, are easily preserved in the sedi, ment. Numerous dead tubes occur with the living ani- nrals and may constitute nearly 100"k ol the total num- ber of tubes (Light, 1999). Forming dense assemblages of live and dead tubes, Ditrupa may control the sediment texture. It also provides a substrate for epibionts and rheophile taxa (Di Geronimo et al., 1989; Gambi, 1986; Gambi 8c Jerace, 1997 Ligfu, 1999) and thereby affects species composition and diversity of soft-bottom com- munities. Observations on r. arietina assemblages from 60 to 300 m deep soft-bottoms of lceland reveal that tubes can be densely colonised by brachiopods, solitary scieractinians, barnacles, serpulids, bryozoans, sponges, and foraminiferans. Opercula lre ofren encrusted by foraminiferans, hydrozoans and erect flexible colonies of bryozoans. Most of dead specimens tubes are inhab- ited by sipunculids. Ditrupa is common in Recent Mediterranean sed- iments. In fossil sediments, it can be abundant, often occurring in banks, due to the combined action of gre- gariousness and selective hydrodynamic transport (ten Hove & van den Hurk, 1993). It has been used as an indic;rtor of sedimentary instability (Di Geronimo & Robba, 1 D. arietina from Pliocene and Pleistocene sedi- ments is found together with Hydroid.es noruegicus. Although common in the Recent Mediterranean, borh serpulid species are more abundant in Pleistocene deposits, where they usually are larger than in the Recent. A fine example is given by the \fùrmian CT/1,1 station, where F1. noroegicus and even more D. arietina A new serpulid from Mediterrd.rredn Neogene DISTANCE IV]ETRIC IS I-PEARSON CORRELATION COEFFICIENT AVERAGE LINKAGE I\IETHOD 0 000 DISTANCES 2.000 461 Fig. 3 - Dendrogram of samples of Ditrupa based on all five fac- tors (C/H, C/Arc., max D of apex, rnx C, Arc.), express- ing morphomctric charac- ters, specimens have a markedly large size (P1. 1, Figs. 8, 9). It seems that both species bene- fied of the lower water rcrrpcr- ature. For both localities with Ditrupa brevis an upper circalir- toral palaeoenvironrnenr can be hypothesised. Like other mem- bers of the genus, D. brer,,is can be considered as a species indicating an unstable envi- ronment with low diversity and be used to recognise F{eterogeneous Communities. Comparing sediments containing D. bre.r,ts to Recent ones conraining D. ari etina, a similar ecological niche, at least fron-r Miocene onwards, can be hypothesised. D. brevis seems ro have been replaced by D. arieti- na durrng the Pliocene. In both studied localities, D. breztis co-occurs with warm water taxa, particularly some bryozoan species extinct in the present-day Mediterranean, but still living in tropical Atlantic and Pacific regions (Di Geronimo er aI., 1992; Rosso, pers. comm.). According to the present data, D. brer.,is ts restrict- ed to the Neogene. Conversely, D. arietina continues all through the Pleistocene till the Recent and was especial- ly abund;rnt during cold Quaternary phases of the Mediterranean. Behaviour. Many tubes oÎ D. breois and D, arietina show a cir- cular hole bored by gastropod predators. Two types can be distinguished: distinctive countersunk holes vrith ber'- elled edges due to naticids, and smaller holes with nearly straight edges, made by mr-rricids (P1. 2, Figs. 2, 4). Records of borer-attachs upon serpuloidean tubes (due to nudibranch, muricid and thaidid gastropods) are frequent (ten Hove. 199,1;. In the examined marerial, drillings mainly occur near the mid point of the rubes, most commonly on its concave side. Similarly, the solitary coral Caryopbyllia smithi encrusting D. arietina (Wilson, 1.976) matnly occurs on the concave side, between the mid point and the anterior end of the tube. These data suggesr that the Dttrupa tube lies horizontally on rhe sediment. This is in agreemenr with ten F{ove E Smith (1990) observations r.hat D. arietina, when placed on the sediment surface, is 462 R. Sanfilippo able to turn over its tube from lying on the right or left sides to lying on the convex side. Thus, only the concave side is always available for colonisators andlor preda- tors. Notwithstanding this, the same aurhors also observed that Ditrupa can be partially buried, with the two tube ends emerging from the sediment. Conversely, Gambi (1986) assumed that Ditrwpa lives vertically buried in the sediment, with only the anterior end of its tube protruding above the surface. Wilson (1976) observed that tubes had the apex slight buried and the convex side turned upwards. These latter models do not explain that on live Ditrwpa the corals are attached, generally, near the mid point of the tube (settling on the concave side) and that bore-hole by muricids (preying only on epifauna, Rey- ment, 1966; Taylor, 1970) occur in the same posirion. The presence of Hydroìcles noraegicus, matnly coiled around the anterior end of the tube, suggests that the posterior end of rhe tube was buried within the sed- iment (obliquely or almost horizontally). Observations in aquarium reveal that Ditrupa ís a filter-feeder (ten Hove & Smith, 1975) although observed life position have implied that deposit-feeding might occur (Hong, 198a). The worm is able to burrow in fine sediments using the branchial crown, thus vary- ing its posture (Lighq 1999). lmm Fig. 4 - Different positions of Drtru- p.r orr rhc.oIr borronr. r, tube n'ith only the anterior end exposed; b) tube hori- zontally buried with the two end5 expo5ed: c.1 rubc lying horizontally above the sedr- Ítenl. To summarise, it can be assumed that Ditrupa can live in different postures: tube with only the anterior end exposed, at more or less steep angle (Fig. 4:r) ; tube buried horizontally in the sediment, with the two ends above the surface (Fig. ab); tube lying horizontally above the sediment (Fig. ac) . The actual position probably reflects the sedimen- tation rate, suggesting rhe Ditrupa's capability of react- ing to sediment dynamics. Acknooledgements. I am indebted to C. Barbera (Dipartimenro di Paleontologia, Napoìi) for loaning toporypic material. I also thank H.A. ten Hor.e (Instituut voor Taxononische Zoologre, Amsterdam) and H. 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