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J. Paleont., 80(1), 2006, pp. 146161

Copyright 2006, The Paleontological Society

0022-3360/06/0080-146$03.00

FOSSIL FISHES FROM THE LOWER TRIASSIC OF MAJIASHAN, CHAOHU,ANHUI PROVINCE, CHINA

JINNAN TONG,1 XIUGAO ZHOU,1 DOUGLAS H. ERWIN,2 JINGXUN ZUO,1 AND LAISHI ZHAO1

1GPMR and BGEG Laboratories, China University of Geosciences, Wuhan 430074, [email protected], and 2Department of Paleobiology,NMNH, Smithsonian Institution, Washington, DC 20560

ABSTRACTThe fossils described here were collected from the Lower Triassic (Olenekian) at two Majiashan sections in Chaohu City,Anhui Province, East China. Nine species belonging to five genera are introduced, including a new genus, Chaohuichthys, and someundetermined or unnamed fish specimens are discussed. The fish assemblage from Majiashan covers most of the Lower Triassic marinebony fish taxa known from China.

INTRODUCTION

MARINE INVERTEBRATES have been well studied during thePaleozoic and Mesozoic biotic revolution (Erwin, 1993;Yin et al., 2000), but marine vertebrates are quite poorly under-stood in comparison. Unlike organic fossil elements such as fishteeth and conodonts, bony vertebrate skeletons have been poorlystudied in China, perhaps because of the scarcity or incomplete-ness of the fossils. The many well-developed marine PermianTriassic sequences in South China have made the area a classicregion for the study of PaleozoicMesozoic transitional events.The sequences cover various paleogeographic facies and containrich fossils (Yang et al., 1987, 1993). Early Triassic fossils doc-umenting the postextinction biotic recovery are also quite com-mon in China. However, the marine bony fishes previously re-ported in China are relatively scattered (Fig. 1) and the fossilsand taxa are limited.

The first bony fish fossils reported from China were from thebasal Yanan Formation (Yanan Series) in Qilingou, Hengshan,north Shaanxi (Chou and Liu, 1957). Five species in five generawere described, including three indeterminate species. This re-mains the most diverse fauna described from the Triassic of Chinaand includes members of four families: the Palaeoniscidae, Ac-rolepidae, Perleididae, and Saurichthyidae. However, the authors

did not indicate whether all these specimens were from the samehorizon. The fossils were assigned an age of not later than MiddleTriassic by comparison with fossils from other regions of theworld. Chang and Jin (1996) placed these fossils in the LowerTriassic but indicated that they were from continental deposits.Liu et al. (1999), by contrast, suggested these species were marineand of Late Triassic age. The Yanan Formation is now placed inthe Jurassic based on the regional geology (Ma, 1998).

A Lower Triassic coelacanth caudal fin was described as Sin-ocoelacanthus fengshanesis Liu, 1964 from Fengshan, Guangxi,Southwest China by Liu (1964). Su (1981) studied a fish specimencollected from Hexian, Anhui Province, by a Hydroelectric En-gineering Team and established a new species, Perleidus yangtz-ensis Su, 1981. He deduced that the specimen was of Early Tri-assic age. He also noted that the Geological Survey of Anhui

Province found some perleidid fossils from the Lower Triassic ofMajianshan, Chaohu, Anhui, but these fossils have not previouslybeen studied. Another perleidid genus and species, Plesioperlei-dus dayeensis Su and Li, 1983, was created by Su and Li (1983)on the basis of a specimen from the Fourth Member of the DayeFormation in Tieshan, Huangshi, Hubei Province. However, eachof these new species was based upon only a single specimen.More Lower Triassic bony fish fossils were described from Qing-shan, Jurong, Jiangsu Province, by Qian et al. (1997) and Liu etal. (2002). At least four genera and eight species were recognized,which belong to two families, the Perleididae and Parasemiono-tidae. In addition, Saurichthys Agassiz, 1834 was observed in the

Lower Triassic of Longtan, Nanjing, Jiangsu Province (Su and Li,1983; Liu et al., 2002), although there has been no detailed studyof these fossils. Jin et al. (2003) reexamined some perleidid fishspecies from the Lower Triassic of the Lower Yangtze region andindicated that the type species of Perleidus Alessandri, 1910 (P.altolepis Alessandri, 1910), named from the Middle Triassic ofItaly, has a caudal fin with epaxial rays but the perleidid speci-mens from the Lower Triassic of South China lacked such a cau-

dal fin. Therefore, they placed Perleidus yangtzensis and Perlei-dus jiangsuensis Qian et al., 1997 into the genus Zhangina Liu(in Liu et al., 2002).

During recent investigations to identify a Global StratotypeSection and Point (GSSP) for the InduanOlenekian boundary inSouth China, we discovered a diverse Lower Triassic bony fishassemblage in Chaohu, Anhui Province. Chaohu is a medium-sized city of Anhui Province, East China, 45 km to the southeastof Hefei, the capital of Anhui Province (Fig. 1). It is situated atthe northern margin of the relict Lower Yangtze Block and hasthe deepest Lower Triassic sediments so far observed on theblock. The Lower Triassic sequence is continuous and the fossilsare generally well preserved. Chaohu has been selected as thetype area of the Chaohuan Stage, the upper stage of the LowerTriassic in the Chinese chronostratigraphic table (Tong et al.,

2001), as well as a possible candidate area of the GSSP of theInduanOlenekian boundary (Tong et al., 2003). The Lower Tri-assic is distributed in the northwestern suburbs of Chaohu Cityand constitutes the core of the Pingdingshan-Majiashan Syncline(Fig. 2). Lithostratigraphically it is composed of the Yinkeng,Helongshan, and Nanlinghu formations. The InduanOlenekianboundary is located in the upper part of the Yinkeng Formationaccording to both conodont and ammonoid data (Tong et al.,2003). Four Lower Triassic sections have been carefully studiedin the area (Tong et al., 2002) and the bony fish fossils were foundat three sections (Fig. 2), all from the upper part of the Helong-shan Formation. However, only one incompletely preserved spec-imen was found at the West Pingdingshan Section while manyfish fossils were collected at the North Majiashan and South Ma-jiashan sections. The previously reported perleidid fossils were

also from the South Majiashan Section but at a different horizon,according to the stratigraphic description of the section (Wang,1984), though nothing but a fossil list was presented. Chen (1985)reported that some Saurichthys coexisted with ichthyosaurs in theupper part of the Lower Triassic Nanlinghu Formation at Maji-ashan but no details were mentioned.

MATERIAL AND METHODS

The specimens at the North Majiashan Section are found ingrayish green, thin-bedded calcareous mudrock and are preservedalong the bedding surfaces. At the South Majiashan Section thefossils are in black marl concretions intercalated with dark gray,


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147TONG ET AL.LOWER TRIASSIC FISHES FROM ANHUI PROVINCE, CHINA

FIGURE 1Distribution of localities yielding Lower Triassic bony fishesin South China. 1, Fengshan, Guangxi; 2, Huangshi, Hubei; 3, Chaohu,Anhui; 4, Hexian, Anhui; 5, Jurong, Jiangsu; 6, Longtan, Nanjing,

Jiangsu.

FIGURE 2Geological map of the northwestern Chaohu and the locationsof the Lower Triassic sections. A

1 A

2, South Majiashan Section (the

classic Majiashan section); B, North Majiashan Section; C, West Ping-dingshan Section; D, North Pingdingshan Section; S

2, Middle Silurian;

D3, Upper Devonian; C

1, Lower Carboniferous (Mississippian); C

2, Up-

per Carboniferous (Pennsylvanian); P1, Lower Permian; P

2, Middle

Permian; P3, Upper Permian; T

1y, Lower Triassic Yinkeng Formation;

T1h, Lower Triassic Helongshan Formation; T

1n, Lower Triassic Nan-

linghu Formation; T2, Middle Triassic; Q, Quaternary.

thin-bedded micrite limestone and nodular limestone. The fishesfound at the North Majiashan Section are mostly the coelacanthChaohuichthys majiashanensis n. gen. and n. sp. (CMR701CMR706) and some distinctive but poorly preserved (and henceindeterminate) coelacanths (CMR707CMR709) and actinopter-ygians (CMR713715). All the fossils collected at the South Ma-jiashan Section are actinoperygians, including the perleidid Ple-sioperleidus yangtzensis (Su, 1981) (J2203), P. dayeensis Su andLi, 1983 (J2204), P. jiangsuensis (Qian et al., 1997) (J2201J2202), and parasemionotid Jurongia fusiformis Liu (in Liu et al.,2002) (J2208J2209), Qingshania cercida Liu (in Liu et al., 2002)(J2205J2207), and Suius cf. S. brevis Liu (in Liu et al., 2002)(J2210). Since the dermal bones in the skull of Chaohuichthysmajiashanensis were carbonized so that the boundaries betweenthe bones are indistinct, the carbonized dermal bones on thecheeks are removed to reveal the pterygoid and metapterygoid(CMR701).

All specimens are deposited in the Museum at the China Uni-versity of Geosciences (CUGM) in Wuhan.

SYSTEMATIC PALEONTOLOGY

Class OSTEICHTHYES Huxley, 1880Subclass ACTINOPTERYGII Woodward, 1891

Order PERLEIDIFORMES Berg, 1940Family PERLEIDIDAE Brough, 1931

Genus PLESIOPERLEIDUS Su and Li, 1983

Plesioperleidus SU AND LI, 1983, p. 10.Zhangina LIU IN LI U ET AL., 2002, p. 31.

Zhangina LIU IN JIN ET AL., 2003, p. 170.

Type species.Plesioperleidus dayeensis Su and Li, 1983.Included species.Plesioperleidus yangtzensis (Su, 1981), Ple-

sioperleidus jiangsuensis (Qian et al., 1997).Diagnosis.Small to moderate size, fusiform in body shape;

dermal cranial bones ornamented with tubercles; relatively broadskull roof; post-temporals widely separated; supraorbital sensorycanal traversing the length of parietal, pit-lines of parietal absent;single rostral; no suborbital, spiracular, and postspiracular ossi-cles; fewer than four supraorbital bones; maxilla palaeoniscoid-like; mandible slender, wedge-shaped and without coronoid

process; marginal teeth styliform, internal teeth hemispherical;operculum smaller than suboperculum, broad preoperculum ver-tical or slightly inclined forward, three to four branchiostegals;about 50 lateral scale rows; dorsal ridge-scales developed; fin raysof all fins except caudal fin unjointed proximally, all fins withfringing fulcra.

Occurrence.Lower Triassic (Olenekian) of southern China,including the Fourth Member of the Daye Formation in Huangsi,Hubei Province (Su and Li, 1983), upper part of Lower QinglongFormation in Mt. Qingshan, Jurong, Jiangsu Province (Qian et al.,1997; Liu et al., 2002; Jin et al., 2003), Lower Triassic in Mt.Simashan, Hexian, Anhui Province (Su, 1981), and HelongshanFormation in Mt. Majiashan, Chaohu, Anhui Province (this pa-per).

Discussion.

Plesioperleidus was established by Su and Li(1983) on the basis of a well-preserved fossil, including a bodyspecimen and its counterpart, from the Fourth Member of theLower Triassic Daye Group at a marble plant in Huangshi, Hubei.The type species was assigned to P. dayeensis and the type spec-imens (T057/31) are deposited in the Geological Museum ofHubei Province. This genus is similar to Perleidus in general as-pects such as body shape, relative position of paired fin to medianfin, cheek, operculum, segmentation of fin rays, and numbers ofrays in dorsal and anal fins equal to endoskeletal supports, but itsvertical and broad preoperculum, shorter postorbital of maxilla,marked longitudinal ridges and ganoine processes ornamented on


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148 JOURNAL OF PALEONTOLOGY, V. 80, NO. 1, 2006

FIGURE 3Plesioperleidus yangtzensis (Su, 1981). Lateral view, CUGM J2203a.

the exposure of scales, and developed dorsal ridge-scales, mostlyspinous, are clearly different from Perleidus.

In their study of the Lower Triassic perleidid fish fossils fromthe upper part of the Lower Qinglong Formation at Qingshan,Jurong County, Jiangsu Province, Liu et al. (2002) described Per-leidus piveteaui Lehman, 1952, Perleidus aff. P. madagascarien-sis Piveteau, 1934, and Perleidus eurylepidotrichia Liu in Liuet al., 2002, and established a new genus, Zhangina, with the typespecies Zhangina cylindrica Liu in Liu et al., 2002. The key char-acters of Zhangina are moderate size, long-cylindrical in bodyshape; middle part of palaeoniscoid-type maxilla having a peculiarconcavity; radials of pectoral fin developed; and two median gu-lars. Reexamining the perleidid fishes from the Lower Yangtzeregion, Jin et al. (2003) indicated that the concavity in the middlepart of the maxilla, which was regarded as a key character of

Zhangina by Liu et al. (2002), does not exist in the holotypes.This cavity might have been caused by damage when the speci-men was split. The previously described pregular and postgularare actually the infrahyal and ceratohyal, respectively (Jin et al.,2003, p. 171). Thus they indicated that Z. cylindrica, the typespecies of Zhanginia, was the synonym of Perleidus jiangsuensisQian et al., 1997. Since the peculiar concavity in the middle partof the maxilla was a key character of Zhangina Liu, the definitionof its type species is not accurate. The other characters show littledifference from Plesioperleidus, and Zhangina is hereby regardedas a later synonym of Plesioperleidus. The species Perleidus

yangtzensis and Perleidus jiangsuensis included in Zhangina byJin et al. (2003) are, therefore, placed into Plesioperleidus. As thegenus Plesioperleidus Su and Li previously included only the typespecies, P. dayeensis, but the holotype of the type species has

only the operculum and cheek bones preserved and the other partsare absent, the diagnosis provided by Su and Li (1983) is incom-plete. Jin et al. (2003) revised the diagnosis of Zhangina in theirstudy of the perleidid fish fossils from the Lower Yangtze region.The diagnosis presented here of the genus Plesioperleidus is anintegration of the diagnoses of Su and Li (1983) and Jin et al.(2003).

Jin et al. (2003) indicated that the type species of Perleidus, P.altolepis (Deecke, 1888), has a caudal fin with epaxial rays, thusthe Lower Triassic perleidid species previously placed in Perlei-dus without such a caudal fin should be excluded from the genus.We agree with them that the Lower Triassic perleidids of the

Lower Yangtze region should not be included in the genus Per-leidus.

PLESIOPERLEIDUS YANGTZENSIS (Su, 1981) new combinationFigure 3

Perleidus yangtzensis SU, 1981, p. 107110, figs. 15, pl. 1.Zhangina yangtzensis JI N ET AL., 2003, p. 175178, figs. 5, 6.

Diagnosis.Operculum obviously smaller than suboperculum,subtriangular; dorsal margin of suboperculum inclined posterior-ly; preoperculum broad, upright; maxilla behind orbital relativelyshort and subtriangular, about two-fifths of maxillary length;scales well ornamented with ridges and their posterior marginserrated.

Description.The skull is relatively short, about 35 mm long,

and slightly shorter than high, 39 mm. The preserved specimenis 80 mm long. Preoperculum broad, almost covering the wholecheek, anterior and posterior margins nearly vertical, dorsal mar-gin arched, ventral margin tilting in posteroventral direction andfirmly connected with posterior part of maxilla. Maxilla behindorbital relatively short and subtriangular, about two-fifths of max-illary length. Operculum smaller than suboperculum, subtriangu-lar, wide ventrally and narrow dorsally, posterodorsal marginarched, anterodorsal margin sunken, ventral margin slightly pro-jecting and tilting ventro-forward. Suboperculum larger thanoperculum, anterior margin straight and tilting backward, poste-rior margin projecting in broad arch, posterodorsal angle uprisingapparently, dorsal margin tilting in anteroventral direction, andventral margin nearly straight. Extrascapula triangular. Post-tem-poral well developed, broad anteriorly and narrow posteriorly,

posterior margin rounded, widely separated. Dermohyal wide dor-sally and pointed ventrally as a reversed triangle. Branchiostegalrays six in number, sturdy, the first one the broadest. Supracleith-rum, cleithrum, and postcleithrum fully developed. Dermal bonein skull ornamented with fully developed tubercles. Pectoral finlarge, composed of 15 sturdy fin rays unjointed proximally. Scalesrhombic, relatively thick and large, and flank scales in severalrows behind pectoral girdle higher than wide, from which thescales become less high toward dorsal and ventral sides and pos-terior part of trunk. The exposed hind part of scale covered bythicker ganoid layer with ganoid ridges and grooves running ros-trocaudally. Posterior margins of scales serrated.


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Material examined.A specimen without the posterior part oftrunk and the anterior part of skull preserved. CUGM J2203a andcounterpart J2203b.

Occurrence.Upper part of the Helongshan Formation at theSouth Majiashan Section, Chaohu.

Discussion.This species was named by Su (1981) on the ba-sis of a specimen from a Lower Triassic marl concretion in Hex-ian, Anhui Province. His specimen is incomplete, lacking the pos-

terior part of the trunk and the tail. He placed this species intothe genus Perleidus and compared it with the Lower Triassic Per-leidus piveteaui from Madagascar. Jin et al. (2003) believed thatPerleidus yangtzensis was very similar to Zhangina jiangsuensis(Qian et al., 1997); the main observed difference was in the widthof maxilla and relative length of the part behind orbital, and thedevelopment of ridges and grooves on scales and serration of thehinder margin of scale. Perleidus yangtzensis has a relatively wideand short maxilla, the part posterior to the orbital about two-fifthsof maxillary length, scales with closely spaced ridges and grooveswith a serrated posterior margin, while Zhangina jiangsuensis hasa narrow and long maxilla, the part posterior to the orbit aboutone-third of maxillary length, most scales smooth on the surfaceand without a serrated posterior margin, but some scales withridges and grooves and a serrated posterior margin. Therefore, Jinet al. (2003) placed Perleidus yangtzensis into the genus Zhan-gina. As Zhangina is a synonym of Plesioperleidus, the speciesis here renamed as Plesioperleidus yangtzensis (Su, 1981). Thedifference between Plesioperleidus yangtzensis and Perleidus piv-eteaui is evident because the suborbital and spiracular present inPerleidus piveteaui do not occur in Plesiperleidus yangtzensis.

PLESIOPERLEIDUS DAYEENSIS Su and Li, 1983Figure 4

Plesioperleidus dayeensis SU AND LI, 1983, p. 1014, figs. 24, pl. 1.

Diagnosis.Operculum subquadrate and smaller than subop-erculum; suboperculum erect and higher than wide, both anteriorand posterior margins straight and nearly parallel, anterodorsaland posterodorsal angles markedly uprising, dorsal margin sunkenevidently, and ventral margin arched broadly; preoperculum erect,

relatively narrow and high; maxilla behind orbital short and tri-angular, about one-fourth of maxillary length; scales well orna-mented with ridges and the posterior margin serrated.

Description.The specimen examined here is fusiform inshape, over 140 mm long and 42 mm deep, and the skull is 34mm long and about 30 mm high. Preoperculum erect, relativelynarrow and high, ventral margin tilting in posteroventral direction,posterodorsal margin arched, sensory canals developed, and firm-ly connected with posterior part of maxilla. Operculum subquad-rate and smaller than suboperculum. Suboperculum erect anddeeper than wide, both anterior and posterior margins straight andnearly parallel, anterodorsal and posterodorsal angles uprisingmarkedly, dorsal margin sunken evidently, and ventral marginarched widely. Dermohyal roundly triangular. Maxilla behind or-bital short and triangular, about one-fourth of the maxillary length.

Mandible low and long, and teeth robust. Extrascapula triangular.Post-temporal large, wide anteriorly and narrow posteriorly, pos-terior margin roundly arched, and widely separated. Supracleith-rum broadly belted. Cleithrum poorly preserved. Postcleithrumbroadly belted. Pectoral fins strong, composed of 14 fin rays un-jointed proximately. Dorsal, pelvic, anal, and caudal fins not pre-served. Scales rhombic, relatively thick and large. Flank scales inseveral rows behind pectoral girdle higher than long, from whichthe scales become lower toward dorsal and ventral sides and theposterior part of trunk. The exposed hind part of scales coveredby relatively thick ganoid layer with ganoid ridges and groovesrunning rostrocaudally. Posterior margin of scale serrated.

Material examined.A nearly completely preserved specimenlacking orbital region, rostral and dorsal, pelvic, anal and caudalfins. CUGM J2204a and counterpart J2204b.


Discussion.These specimens are coincident with Plesioper-leidus dayeensis except for their smaller size. It differs from Ple-sioperleidus yangtzensis in its relatively narrow and deep preo-

perculum, subquadrate operculum, erect suboperculum andevidently sunken dorsal margin, triangular maxilla, and aboutone-fourth of maxillary length.

PLESIOPERLEIDUS JIANGSUENSIS (Qian et al., 1997)new combination

Figure 5

Perleidus jiangsuensis QIAN ET AL., 1997, p. 6567, pl. 1, figs. 1, 2.Perleidus piveteaui LIU ET AL., 2002, p. 2829, pl. 11.Zhangina jiangsuenesis (QI AN ET AL., 1977), JI N ET AL., 2003, p. 171

175, figs. 24.

Diagnosis.Operculum nearly fan-shaped and slightly smallerthan suboperculum; maxilla relatively narrow and long, part be-hind orbital about one-third of maxillary length; pectoral fin smalland endoskeletal supports slender; flank scales behind pectoralgirdle relatively broad and high, most of scales unornamented andnot serrated at posterior margin.

Description.The fish is small to medium in size and fusiformin shape, about 135 mm long and 41 mm deep. Head relativelyshort, higher than long. However, no rostral and orbital regionwas preserved in the skull and maxilla, and mandible only partlypresent in our specimens. Preoperculum erect and broad, almostoccupying the whole cheek; anterior margin straight and posteriormargin nearly straight, sensory canal well developed, ventral mar-gin nearly straight and tilting in posteroventral direction, firmlyconnected with the posterior part of maxilla. Operculum slightlysmaller than suboperculum, nearly fan-shaped with a nearlystraight anterior margin, straight ventral margin and arched pos-terodorsal margin. Suboperculum roughly fan-shaped with nearlystraight anterior margin, straight dorsal margin and arched pos-

teroventral margin. Maxilla relatively narrow and long, with ashort part behind orbital, about one-third of maxillary length.Mandible low and long with sturdy teeth. Dermohyal small androundly triangular. Extrascapula triangular. Post-temporal large,wider anteriorly and narrow posteriorly, and posterior marginroundly arched, and widely separated. Dermal bones in skull or-namented with well-developed tubercles.

Supracleithrum short and broadly belted; both cleithrum andpostcleithrum poorly preserved. Pectoral fins relatively small, andendoskeletal supports short and fine but enlarged proximally anddistally. Fin rays incompletely preserved, about 15 fin rays un-jointed proximally but branched at distal end.

Pelvic fins distant from pectoral fins and close to anal fin, nar-row proximally and situated between the eighteenth and twenty-first rows of scales, with three short fin spines and eight fin rays

unjointed proximally and branched distally. Dorsal fin situated inthe posterior part of fish and on the dorsal side between pelvicand anal fins, long proximally, and containing three fin spines andabout eighteen fin rays unjointed proximally but not preserveddistally. Pelvic fin of three fin spines and seven fin rays unjointedproximally and branched distally. Anal fin of three fin spines andseven fin rays unjointed proximally and branched distally. Caudalfin preserved only proximally.

Scales of about 42 rows along the lateral line. Flank scalesbehind pectoral girdle considerably higher than wide, about twicewidth. From this area the scales gradually decrease in height andbecome rhombic in shape toward dorsal and ventral sides and the


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FIGURE 4Plesioperleidus dayeensis Su and Li, 1983. 1, Lateral view, CUGM J2204a; 2, lateral impression, CUGM J2204b.

posterior part of body. Most scales unornamented and not serratedon their posterior margin.

Material examined.Four relatively well-preserved specimens,CUGM J2201a and counterpart J2201b, J2202a and counterpartJ2202b. J2201a and counterpart J2201b are an incompletely pre-

served fish with a skull lacking rostral part, maxilla and mandibleincomplete, poorly preserved orbital bones, and trunk partly lack-ing fins. J2202 and counterpart J2202b are a partly preserved fishwith a skull lacking rostral, orbital region and part of operculum,a trunk lacking dorsal and posterior parts, most of pectoral girdle,and no dorsal, pelvic, anal, and caudal fins.


Discussion.These specimens are quite coincident with thosedescribed by Qian et al. (1997) and Jin et al. (2003). This speciesdiffers from Plesioperleidus yangtzensis and Plesioperleidus day-eensis mainly in its operculum being nearly fan-shaped and slight-ly smaller than suboperculum, maxilla relatively narrow and longand its part behind orbital about one-third of maxillary length,pectoral fins small and endoskeletal supports slender, and most of

scales unornamented and not serrated at posterior margin (Fig. 6).Order PARASEMIONOTIFORMES Lehman, 1966

Family PARASEMIONOTIDAE Stensio, 1932Genus JURONGIA Liu in Liu et al., 2002

Jurongia LIU IN LIU ET AL., 2002, p. 34.

Type species.Jurongia fusiformis Liu in Liu et al., 2002.Included species.Only the type species.Diagnosis.Fish small in size and fusiform in shape; opercu-

lum larger than suboperculum; preoperculum subquadrilateral,rather narrow and high, and nearly vertical; interoperculum small

and triangular; maxilla small, not connecting with preoperculumposteriorly; supramaxilla very small.

Occurrence.Lower Triassic (Olenekian) in southern China,including upper part of the Lower Qinglong Formation in Mt.Qingshan, Jurong, Jiangsu Province (Liu et al., 2002; Jin et al.,

2003), and Helongshan Formation in Mt. Majiashan, Chaohu, An-hui Province (this paper).

Discussion.Liu (in Liu et al., 2002) established this genusbased upon the type species Jurongia fusiformis, which ischaracterized by an operculum larger than suboperculum, preo-perculum not connecting with maxilla, and supramaxilla and in-teroperculum present; thus it is included in the family Parase-mionotidae.

The family Parasemionotidae was established by Stensio(1932) on the basis of the genus Parasemionotus Piveteau,1929 discovered in the Lower Triassic of northwestern Mada-gascar. There are 12 genera included in this family, amongwhich nine genera were found in Madagascar while the otherthree were described from Jurong, Jiangsu Province. Of thenine genera from Madagascar, Lehmanotus Beltan, 1968, De-

villersia Beltan, 1968, and Piveteaunotus Beltan, 1968 wereestablished based only on endocrania. Icarealcyon Beltan,1980 was based on a postcranial specimen. It is impossible tocompare Jurongia with these genera. The other five genera,i.e., Watsonulus Piveteau, 1934, Parasemionotus Piveteau,1934, Thomasinotus Lehman, 1952, Stensionot us Lehman,1952, and Jacobulus Lehman, 1952, were well defined by de-scription of complete specimens, in which the preoperculum isclearly differentiated and the pattern of differentiation is dis-tinct in each genus. Thus the differentiation of the preopercu-lum is the main basis to distinguish these genera and their spe-cies (Lehman, 1952). Jurongia is more similar to


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FIGURE 5Plesioperleidus jiangsuensis (Qian et al., 1997). 1, Lateral view, CUGM J2201a; 2, lateral impression, CUGM J2201b; 3, lateral view,CUGM J2202a; 4, lateral impression, CUGM J2202b.

Parasemionotus than to other known genera in the family inhaving a smaller and deeply fusiform body, small and freemaxilla, and narrow and high preoperculum, though their preo-percula and opercula are clearly different in shape. In Jurongiathe preoperculum is subquadrilateral and the suboperculum

smaller than the operculum and parallelogramic in shape, whilein Parasemionotus the preoperculum is elliptical, the subop-erculum larger than the operculum and irregular in shape. Ju-rongia also somewhat resembles Stensi onot us but their preo-percula are different in shape and easily recognized.


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FIGURE 6Comparison of the opercular and bones on cheek (right-lateralview) among some species of Plesioperleidus Alessandri, 1910. 1, Ple-sioperleidus jiangsuensis; 2, P. dayeensis; 3, P. yangtzensis. Br, bran-chiostegal ray; Dh, dermohyal; Md, mandible; Mx, maxilla; Op,operculum; Poc, preopercular canal; Pop, preoperculum; Sop, Subop-erculum.

FIGURE 7Jurongia fusiformis Liu in Liu et al., 2002. 1, Lateral view, CUGM J2209a; 2, lateral impression, CUGM J2209b; 3, lateral view, CUGMJ2208.

JURONGIA FUSIFORMIS Liu in Liu et al., 2002Figure 7

Jurongia fusiformis LIU IN LIU ET AL., 2002, p. 3436, pl. 42, fig. 4.

Diagnosis.As for genus.Description.Fish small in size and fusiform in shape, about

125 mm long. Operculum large, larger than suboperculum, andslightly tilting forward; the height almost equal to the depth; ven-tral margin straight, anterior and posterior margins nearly straight,and posterodorsal and dorsal margins slightly arched. Suboper-culum shaped like a parallelogram, twice as long as high. Inter-operculum small, triangular, and situated at the anteroventral sideof operculum. Preoperculum subquadrilateral, rather narrow andhigh, and nearly vertical, with an evident sensory canal, posterior

margin projecting in arch, but anteroventral and anterodorsal partsbroken. Post-temporal subtriangular, ventral margin nearlystraight, anterior margin straight and tilting forward, connectedwith extrascapula. Extrascapula small and subtriangular. Maxillanot contacted with preoperculum. Supramaxilla small. Branchios-tegal rays broadly belted with four rays preserved. Supracleithrumrelatively broad and large with marked sensory canal. Cleithrumarched and ventral branch slightly enlarged. Postcleithrum com-posed of two pieces and the dorsal one narrow and high whilethe ventral short and wide. No dorsal and caudal fins preservedand only the proximal parts of pectoral, pelvic, and anal fins ob-served. Scales rhombic, covered by thick ganoid layer, and theexposed posterior part smooth.

Material examined.An incompletely preserved specimen(CUGM J2209a and counterpart J2209b) lacking dorsal side, or-bital region, rostral, parts of maxilla and mandible, dorsal and


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FIGURE 8Qingshania cercida Liu in Liu et al., 2002. 1, Lateral view, CUGM J2206a; 2, lateral impression, CUGM J2206b; 3, top view, CUGMJ2207; 4, lateral view, CUGM J2205.


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FIGURE 9Suius cf. S. brevis Liu in Liu et al., 2002. 1, Lateral view,CUGM J2210a; 2, lateral impression, CUGM J2210b.

caudal fins and parts of pectoral, pelvic, and anal fins. Anotherspecimen (CUGM J2208) of only the main part of the skull andpectoral girdle but lacking orbital region, rostral, and parts ofmaxilla and mandible.


Discussion.Our specimens are basically coincident with thecharacteristics of Jurongia fusiformis established by Liu et al.(2002) in the Lower Triassic of Qingshan, Jurong County, JiangsuProvince, except that a backward depression on the anterodorsalmargin of the preoperculum occurs in J2208, which might be asmall preoperculum subdivided from the preoperculum or mightbe a broken specimen. This must be confirmed by more speci-mens.

Genus QINGSHANIA Liu in Liu et al., 2002

Qingshania LIU IN LIU ET AL., 2002, p. 36.

Type species.Qingshania cercida Liu in Liu et al., 2002.Included species.Only the type species.Diagnosis.Small or moderate sized fish, with a slender fu-

siform or shuttlelike shape; preoperculum narrow and high, fu-siform, and vertical.

Occurrence.Lower Triassic (Olenekian) of southern China,including upper part of the Lower Qinglong Formation in Mt.Qingshan, Jurong, Jiangsu Province (Liu et al., 2002; Jin et al.,2003), and Helongshan Formation in Mt. Majiashan, Chaohu, An-hui Province (this paper).

Discussion.This genus differs from Jurongia mainly in its

long, fusiform shape, relatively broad suboperculum, and narrow-er and fusiform preoperculum while the latter has a short, fusi-form shape, relatively low and long suboperculum, and nearlyquadrate preoperculum. This genus is similar to Watsonulus inthe shape and size of operculum and suboperculum but Qing-shania has a fusiform preoperculum while the preoperculum ofWatsonulus is ovoid.

QINGSHANIA CERCIDA Liu in Liu et al., 2002Figure 8

Qingshania LIU IN LIU ET AL., 2002, p. 3638, pl. 4, figs. 3, 4; pl. 5, fig. 1.

Diagnosis.As for genus.

Description.Fish of relatively small size, long fusiformshape, 122 mm long and 36 mm deep. Skull about 40 mm long,the length slightly more than the depth of body. Operculum andsuboperculum broad and operculum larger than suboperculum.Operculum nearly fan-shaped, ventral margin straight, ventral partof anterior margin straight and dorsal part slightly concave, pos-terodorsal margin projecting in arch. Suboperculum broad, shapedlike a parallelogram, with ventral and dorsal margins nearly

straight and anterior and posterior margins tilting in posterodorsaldirection, and at its anteroventral corner situated a triangular in-teroperculum. Preoperculum nearly upright, narrow and high, fu-siform. Two suborbital bones preserved. Maxilla subtriangular,high posteriorly and low anteriorly. Border between supramaxillaand maxilla infinite. Premaxilla small. Teeth robust and conical.Mandible not preserved. Extrascapula high and triangular and itsposterior part connected with broad post-temporal while the an-terior with dermopterotic. Parietal short and nearly quadrate.Frontal long and broad. Nasal and rostral not preserved. Bran-chiostegal rays narrowly belted with three preserved. Pectoral gir-dle of supracleithrum short but wide; cleithrum arched and ventralbranch enlarged; postcleithrum composed of two bones, amongwhich the dorsal one is clearly longer than the ventral. Pectoralfin strong with about 11 fin rays unjointed proximally but artic-

ulate and branched distally. Pelvic fins displaced from pectoralfins and close to anal fin, with seven fin rays in each. Anal finbigger than pelvic fins and longer proximally as well, nine en-doskeletal supports, which are spinal proximally and obtuse dis-tally to joint with fin rays, rays equal to endoskeletal supports innumber, unjointed proximally but articulate and branched distally.Dorsal fin poorly preserved. Distal part of caudal fin absent, prob-ably hemiheteocercal; dorsal lobe proximally covered by longrhombic scales but no scales on ventral lobe; fin rays articulateproximally, and the articulations wider than long. Scales rhombic-shaped, covered by thick ganoid layer and the exposed hind partsmooth, 43 rows of scales on lateral line and the flank scalesbehind pectoral girdle higher than long.

Material examined.A nearly complete specimen (CUGMJ2205) lacking orbital region, rostral, mandible, and parts of dor-

sal and caudal fins. Two incomplete specimens (CUGM J2206and J2207) with only skull and anterior part of trunk preserved.Occurrence.Upper part of the Helongshan Formation at the

South Majiashan Section, Chaohu.Discussion.Our specimens accord well with Qingshania cer-

cida named and described by Liu et al. (2002), which is easilydistinguished from Jurongia fusiformis in its long, fusiform body;depth less than the length of the head, fusiform preoperculum,and broader suboperculum.

Genus SUIUS Liu in Liu et al., 2002

Suius LIU IN LIU ET AL., 2002, p. 38.

Type species.Suius brevis Liu in Liu et al., 2002.

Included species.

Only the type species.Diagnosis.Fishes small or medium-sized, fairly fusiform inshape; operculum larger and deeper than suboperculum; intero-perculum developed; maxilla low anteriorly and higher posteri-orly, connected firmly with upright preoperculum; mandible lowand short anteriorly, rapidly increased in height posterior, withangular and suprangular.

Occurrence.Lower Triassic (Olenekian) in southern China,including upper part of the Qinglong Formation in Mt. Qingshan,Jurong, Jiangsu Province (Liu et al., 2002), and Helongshan For-mation in Mt. Majiashan, Chaohu, Anhui Province (this paper).

Discussion.The genus shows transitional characters between


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FIGURE 10Undetermined actinopterygian fishes. 1a, Lateral view, CUGM CMR713a; 1b, lateral impression, CUGM CMR713b; 2, a reversedhemiheterocercal caudal fin, CUGM CMR714; 3, a nearly homocercal caudal fin, CUGM CMR715.

perleidid and parasemmionotid fishes. Its well-developed intero-perculum and mandible with angular and suprangular are obvi-

ously of parasemionotid type, while its maxilla, higher posteriorlyand connected firmly with the nearly vertical preoperculum, is oftypical perleidid type. But Suius is so unique that it differs fromany known genera of the family Parasemionotidae or from thoseof the family Perleididae in having the interoperculum, angularand suprangular. Liu et al. (2002) assigned it tentatively to thefamily Parasemionotidae, which is followed in this paper.

SUIUS cf. S. BREVIS Liu in Liu et al., 2002Figure 9

cf. Suisu brevis LIU IN LI U ET AL., 2002, p. 3839, pl. 6, figs. 1, 2, text-fig. 5.

Diagnosis.Fish small in size; operculum larger than subop-erculum; suboperculum of anteroventral part inclined, indicating

the existence of interopercular bone; maxilla higher posteriorlyand firmly connected with preoperculum.Description.Fish about 90 mm long, and skull about 30 mm

long. Operculum larger than suboperculum. Suboperculum lowand shaped in a long parallelogram, anteroventral part inclined,indicating the existence of interopercular bone, but interopercu-lum not preserved. Hyomandibula uncovered, nearly erect, broad-ly belted, dorsal part tilting forward, a posteriorly extending pro-cessus opercularis in medial-dorsal part, which is broadlytruncated at top and slightly narrower in the lower part. Preoper-culum broken, broad in view of its external mold, firmly con-nected with the posterior part of maxilla. Maxilla short and high


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FIGURE 11Chaohuichthys majiashanensis n. gen. and n. sp. 1, Holotype CMR701, right lateral view; 2, composite reconstruction of the holotypeCMR701; 3, paratype CMR702, right lateral view.

behind orbital and low anteriorly. Mandible and branchiostegalrays not preserved. Parietal subquadrate and frontal long andlarge. The other bones of skull broken. Cleithrum in pectoral gir-dle broadly belted. Scales rhombic-shaped, covered by thick gan-oid layer and the exposed hind part smooth.

Material examined.An incompletely preserved specimenlacking caudal part, anterior part of skull and all the fins. CUGM

J2210a and counterpart 2210b.Occurrence.Upper part of the Helongshan Formation at theSouth Majiashan Section, Chaohu.

Discussion.Our specimen is quite similar to Suius brevisnamed and described by Liu et al. (2002), but some key charac-teristics such as the preoperculum, interoperculum, and mandibleare not preserved in our specimen so that we consider it as aconformis of S. brevis.

Undetermined actinopterygian fishesFigure 10

Discussion.In addition to the taxa described above andmany coelacanth fishes, some actinopterygian fossils (CUGM

CMR713CMR715) were collected from the upper part of theHelongshan Formation at the North Majiashan Section, Chaohu.Among the actinopterygian fishes, CUGM CMR713 andCMR714 are small in size and the length is less than 110 mm,shape fusiform, scales rhombic, tail hemiheterocercal, endo-skeletal supports of fins equal to fin rays in number, but pectoralgirdle and skull weathered and absent. The fossil CUGMCMR715 has only the caudal part preserved, which is of a nar-row and long caudal peduncle covered by rhombic-shapedscales. Though the tail is still hemiheterocercal, it verges onhomocercal. In addition, the fish is obviously bigger. So it shouldbelong to a different genus and species from the specimensCUGM CMR713 and CMR714, but it is difficult to do furtheridentification. Although these fossils could not be assigned tofamily and genus, they at least demonstrate that they coexistedwith the coelacanth fishes to form a diverse fish fauna. Furtherstudies may be possible when better-preserved specimens arecollected.


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FIGURE 12Head of Chaohuichthys majiashanensis n. gen. and n. sp. 1, Holotype CMR701, right lateral view of head and pectoral girdle; 2,composite reconstruction of the head, right lateral view. Acl, Anocleithrum; Ang, Angular; Cl, Cleithrum; Cla, Clavicle; Ecl, Extracleithrum; f,

Frontal; Mptg, Metapterygoid; Op, Operculum; Pa.it, Parieto-intertemporal; Po, Postorbital; Psp, Parasphenoid; Pt, Pterygoid; Q, Quadrate; So,Supraorbital; Splsang, Splenial-supraangular.

FIGURE 13Composite reconstruction of the basal plates of fins in Chao-huichthys majiashanensis n. gen. and n. sp. after CMR701 andCMR702, all right lateral view. 1, Basal plate of anterodorsal fin; 2,basal plate of posterodorsal fin; 3, basal plate of pelvic fin; 4, basalplate of anal fin.

Class OSTEICHTHYES Huxley, 1880Subclass CROSSOPTERYGII Huxley, 1861

Order COELACANTHIFORMES Jarvik, 1942Family COELACANTHIDAE Agassiz, 1838

Genus CHAOHUICHTHYS new genus

Type species.Chaohuichthys majiashanensis n. gen. and n.sp.

Included species.Only the type species.Diagnosis.Fish small in size and nearly fusiform in shape;

operculum subtriangular, narrow and long; pectoral girdle strong,broad and large, with extracleithrum; pectoral fins thoracic; pelvicfins located one-third from the front of trunk, the basal plates

composed of posterior division, anterior division and medial pro-cess, and the anterior division subdivided into anterodorsal andanteroventral processes; anal fin small, opposite to the posteriordorsal fin, the basal plate bifurcate; caudal fin coelacanth-typewith dorsal and ventral lobes almost equal in size.

Description.Skull slightly longer than the depth of body.Skull with very delicate sculpture of tubercles and striate. Parieto-intertemporal broad and anterior part narrower than the posterior.Frontals narrow and long. Supraorbital of three pieces in number.Postorbital broad and large. Parasphenoid with small, bluntly con-ical teeth. Pterygoid with a broad posterior limb and a long an-

terior one, and some small bluntly conical teeth at the dorsal sideof anterior limb. Metapterygoid triangular. Quadrate small. Oper-culum subtriangular, narrow and long. Pectoral girdle strong,broad and large, with extracleithrum. Centra not ossified. Twodorsal fins, the basal plate of the anterior one subtriangular whilethat of the posterior fin bifurcate with thickset anterior processextending forward, slender anteroventral process in anteroventraldirection, and broad posterior process. Pectoral fins thoracic andsmall in size. Pelvic fins one-third from the front of trunk, strong,the basal plates composed of posterior division, anterior divisionand medial process, and the anterior division subdivided into an-terodorsal and anteroventral processes. Anal fin small, oppositeto the posterior dorsal fin, the basal plate bifurcate with slenderanterodorsal and anteroventral processes and broad and short pos-terior division. Caudal fin coelacanth-type with dorsal and ventral

lobes almost equal in size; axial lobe incompletely preserved.Scales ovoid with narrow and rounded posterior edge, and theexposed hind part covered by discrete ganoid ridges.

Etymology.The genus is named for the Chaohu locality,where the type species was found.

Discussion.The coelacanth fishes reported in China includeSinocoelacanthus fengshanensis Liu, 1964 from the Lower Tri-assic Luolou Formation in Fengshan, Guangxi, southwest China.It was established based only upon a caudal fin (Liu, 1964) withnumerous fin rays, 26 rays in the dorsal lobe and 39 in the ventral,so it is distinctly different from the new genus, which has 16 raysin the dorsal lobe and 15 in the ventral. Wang and Liu (1981)


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FIGURE 14Caudal fins ofChaohuichthys majiashanensis n. gen. and n. sp. 1, CUGM CMR703, 2, CUGM CMR704, 3, CUGM CMR705, 4, CUGMCMR706, 5, composite reconstruction of the caudal fin of the paratype CUGM CMR702.

described Changxingia aspratilis Wang and Liu, 1981 and Youn-gichthys xinghuainsis Wang and Liu, 1981 from the Upper Perm-ian Changxing Formation in Meishan, Changxing, Zhejiang Prov-ince. The new genus is distinguished from Changxingia Wangand Liu, 1981 by its smaller body, operculum markedly deeper

than long, pelvic fins situated relatively forward, the basal platesof pelvic fins asymmetrically X-form, caudal fin of fewer fin rays,and endoskeletal supports enlarged proximally and distally. Thenew genus and Youngichthys Wang and Liu, 1981 are similar inbody size and number of caudal fin rays, but the latter has ab-dominal pelvic fins, simply forked basal plates of pelvic fins, rel-atively more neural arches (52 arches in number), and the endo-skeletal supports are not enlarged proximally and distally. Liu etal. (1999) reported an incomplete coelacanth fossil from the Up-per Triassic in Huachi, Gansu Province, Northwest China, whichwas included in the family Laugiidae Stensio, 1932 but was notassigned to a particular genus or species. This fossil has thoracicpelvic fins and thus is different from the new genus.

CHAOHUICHTHYS MAJIASHANENSIS new genus and species

Figures 1115Diagnosis.As for genus.Description.Fish small in size and nearly fusiform in shape,

totally about 140 mm long. The length of skull slightly more thanthe depth of body; skull well ossified but the borders betweenbones difficult to determine due to the carbonization during fos-silization. Post-temporal and extrascapula mostly absent. Parieto-intertemporal broad and anterior part narrower than the posterior.Frontal narrow and long. Supraorbital of three pieces in number.Postorbital broad and large. Parasphenoid broad and with bluntlyconical teeth. Pterygoid with a broad posterior limb, an anteriorlynarrowing anterior limb, and some small bluntly conical teeth at

the dorsal side of the anterior limb. Metapterygoid triangular.Quadrate small and situated at the posteroventral side of posteriorlimb of pterygoid. Operculum subtriangular, narrow and high,dorsal margin nearly straight, posterior margin broadly arched,anterior margin nearly straight, ventral margin subround, tilting

backward. Mandible only hind part preserved. Skull of very del-icate sculpture of tubercles and striate (Figs. 11, 12).

Vertebral centra not ossified, ribs not preserved. About 46 neu-ral arches and neural spines preserved, among which 30 are intrunk and 16 in caudal; on the trunk the anterior 12 neural archesof short and pointed neural spines while the posterior 18 archesof thin and long neural spines; on the caudal the neural spinesmarkedly longer than neural arches, gradually enlarged fromproximal to distal, and truncated at distal tip to connect with en-doskeletal supports in dorsal lobe of caudal fin. Haemal archesand haemal spines preserved only in the posterior part of trunkbefore the commencement of anal fin. Haemal arches and haemalspines around anal fin smallish. Haemal arches and haemal spineson caudal relatively long and robust, haemal spines gradually en-larged from proximal to distal, and truncated at distal tip to con-

nect with endoskeletal supports.Pectoral girdle strong and broad, composed of anocleithrum,

cleithrum, extracleithrum, and clavicle. Anocleithrum not pre-served. Cleithrum robust and broad, curved backward in arch.Extracleithrum relatively short and broad, attached to the posteriorside of the ventral branch of cleithrum. Clavicle large, subtrian-gular, its posterodorsal margin connected with extracleithrum andcleithrum. Pectoral fins thoracic, small, and of nine fin rays.

Pelvic fins larger than pectoral fins, situated posteroventrally ofpectoral fins, relatively far away from anal fin and closer to pec-toral fins, and composed of about 17 fin rays; anterior five rayslengthening in succession and posterior rays shortening in order,


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FIGURE 15Scales of the holotype CUGM CMR701 of Chaohuichthys majiashanensis n. gen. and n. sp., all right lateral view. 1, Scales onanterodorsal side, 2, composite reconstruction of scales on anterodorsal side, 3, scales on posteroventral side, 4, composite reconstruction of scaleson posteroventral side.

medium rays the longest, posterior margin roundly arched. Basalplates of pelvic fins similar to those in Diplurus newarki Schaef-fer, 1948, asymmetrically X-shaped and composed of a posteriordivision, an anterior division and a medial process while the an-terior division subdivided into an anterodorsal process and an an-teroventral process; the anterodorsal process longer and horizon-tally extending forward, the anteroventral process shorter andextending in anteroventral direction to contact the anteroventralprocess on the other side and form a V form; the medial processshorter and broader and its distal end contacting that of the otherside; the posterior division broader and larger and enlarged inposterodorsal part, showing a broadly arched posterodorsal mar-gin (Fig. 13).

Two dorsal fins. Anterior dorsal fin (D1) relatively small, an-

terior margin commencing at the eighth neural arch; composed of

eight fin rays, among which the first one is the coarsest and lon-gest and the other rays shorten in order; basal plate subtriangularwith nearly straight ventral margin, round-arched dorsal angle andlonger anterior margin than posterior margin. Posterior dorsal fin(D

2) situated on the posterodorsal side of body; anterior margin

commencing at the twenty-eighth neural arch; composed of about14 fin rays, distal parts of which are not preserved; basal platebifurcate with a thickset anterodorsal process, which extends for-ward, a slender anteroventral process extending in anteroventraldirection, and a broad and large posterior division of a posteriorpart broader than anterior part and nearly straight posterior mar-gin.

Anal fin located on the posteroventral side of body, oppositeto D

2, containing 13 fin rays; basal plate bifurcate with antero-

dorsal and anteroventral processes spindly, and posterior divisionbroad and short.

Caudal fin coelacanth-type, dorsal and ventral lobes equallysized and of thickset fin rays, axial lobe partly preserved and ofslender rays (Fig. 14). Dorsal lobe composed of 1416 fin rays,anterior four rays closely spaced and the others equally spaced;endoskeletal supports enlarged from middle to both proximal anddistal ends; a transverse line bordering endoskeletal supports anddistal ends of neural arches; border between endoskeletal supportsand proximal ends of fin rays indefinite but an angle apparent atthe joint; fin rays extending not along the direction of endoskeletalsupports but nearly parallel to the axial skeleton; fin rays unjoint-ed proximally but articulated from the middle to distal part. Ven-

tral lobe of 1315 fin rays, anterior rays spaced closely and theothers arranged in nearly equal space; endoskeletal supportscoarse at both ends and fine in the middle, proximal end jointedwith the distal end of haemal arch and distal end jointed with finray at an angle; fin rays unjointed proximally. On the specimenCUGM CMR702, a haemal arch before the anterior margin ofventral lobe is jointed with a short conical fin spine, but the otherfin spines are not preserved. Axial lobe is poorly preserved, andonly three slender fin rays are observed on the specimen CUGMCMR702.

Scales ovoid, posterior edge narrowly arched, and the exposedhind part ornamented with strips of discrete ridges. The exposed


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FIGURE 16Unnamed coelacanth fishes. 1, Right lateral view, CUGM CMR709; 2, right lateral view, CUGM CMR708, 3, left lateral view, CUGMMRC707.

hind part relatively broad and short at anterodorsal side whilenarrow and long at posteroventral side (Fig. 15).

Etymology.This species is named for the locality yielding thefossils, Mt. Majiashan, Chaohu, Anhui Province.

Types.Holotype a nearly completely preserved fish specimen(CUGM CMR701) lacking only rostral and distal part of caudalfin. Paratype a specimen lacking most parts of skull (CUGMCMR702) and four specimens of caudal fin (CUGM CMR703CMR706).

Measurements of holotype (mm).

Total length of body 130

Height of body 29Length of skull 30Height of skull 28From rostral to the commencement of D

140

From rostral to the commencement of D2

75From rostral to the commencement of pelvic fin 48From rostral to the commencement of anal fin 80

Occurrence.Upper part of the Helongshan Formation at theNorth Majiashan Section, Chaohu.

Discussion.As mentioned in the description of the genus, this

new species is distinguished from all known genera and speciesin the family Coelacantidae by a narrower and higher operculum,distinct basal plate of fin, equally sized dorsal and ventral lobeson caudal fin, and fewer and coarse fin rays.

Unnamed coelacanth fishesFigure 16

Discussion.Three other coelacanth specimens (CUGMCMR707CMR709) were collected from the same bed withChaohuichthys majashanensis n. gen. and sp. in the upper part ofthe Helongshan Formation at the North Majiashan Section, Chao-

hu. They might be a new genus or species but the specimens arefew and poorly preserved so that it is difficult to identify them.In specimen CUGM CMR707, a subtriangular operculum and apectoral girdle with extracleithrum are preserved and the centraof axial skeleton are not ossified, thus it should belong to thefamily Coelacanthidae. As its operculum, shoulder girdle, andbasal plate of pelvic fin are clearly different from those in C.majiashanensis, it might be a different genus and species. Amongspecimens CUGM CMR708 and CMR709, CMR709 has two dor-sal fins, centra not ossified, pectoral girdle with extracleithrum,operculum subtriangular, and pelvic fin in thoracic position butnot directly connected with shoulder girdle. Consequently, they


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