Zoological Studies 33(1) 44-64 (1994) A Review of the Muraenid Eels (Family Muraenidae) from Taiwan with Descriptions of Twelve New Records1 2 2 Hong-Ming Chen ,3 , Kwang-Tsao Shao ,4 and Che-Tsung Chen" 21nstitute of Zoology, Academia Sinica, Nankang, Taipei, Taiwan 115, R.O.C_ 31nstitute of Fisheries, National Taiwan Ocean University, Keelung, Taiwan 202, R.O.C. 41nstitute of Marine Biology, National Taiwan Ocean University, Keelung, Taiwan 202, R.O.C. (Accepted June 3, 1993) Hong-Ming Chen, Kwang-Tsao Shao and Che-Tsung Chen (1994) A review of the muraenid eels (Family Muraenidae) from Taiwan with descriptions of twelve new records. Zoological Studies 33(1): 44-64. A total of 42 species belonging to 9 genera and 2 subfamilies of the family Muraenidae are indigenous to Taiwan. The 12 species: Enchelycore bikiniensis, Gymnothorax brunneus, G. javanicus, G_ margaritophorus, G. melatremus, G. nudivomer, G. reevesii, G. zonipectis, Strophidon sathete, Uropterygius macrocephalus, U. micropterus, and U. tigrinus are first reported in this paper. The 7 species: Enchelycore lichenosa, E. schismatorhynchus, Gymnothorax buroensis, G. hepaticus, G. meleagris, G. richardsoni and Siderea thyrsoidea whose Taiwan existence was doubted or lacked specimens in the past are also recorded. Additionly, many species misidentifications or improper use of junior synonyms in previously literature stand corrected in this paper. Two previously recorded species Gymnothorax monostigmus and G. polyuranodon are, lacking Taiwan specimens, excluded. Color photographs, dentition patterns, synopsis, key, diagnosis, and remarks for all 42 species are provided in this paper. Key words: Moray eels, Fish taxonomy, Fish fauna, Anguilliformes. The Muraenidae fishes, commonly called the Gymnothorax /eucostigma species. In 1967 moray eels, are shallow-water reef and crevice­ Chen and Weng reviewed Taiwan specimens of dwelling eels. There are about 110' species of muraenids and assigned a total of 6 genera and morays in the world which belong to the 12 genera 24 species. But among their designations, the two of the 2 subfamilies: Uropterygiinae and Muraeninae species of Thyrsoidea macrura and Strophidon ui (Nelson 1984). This group of fishes is distinguish­ were Strophidon sathete synonyms; the Gym­ ed from other eel families by their larger mouth, nomuraena con cotor specimen was actually S. smaller gill openings, and pectoral and pelvic fin sathete; the Gymnothorax punctatofasciatus identi­ absence. Most species have a stout muscular body fication was also a mistake, it should be an un­ and dark skin pigmentation. described species; their Gymnothorax me/eagris In Taiwan, the earliest moray record is the specimen was actually G. eurostus; both G. me/a­ 1870 Gunther listing of Muraena nubi/a; actually a nospi/us and G. pescadoris should be junior syno­ misdesignation of Gymnothorax chi/ospi/us, Bleeker nyms of G. favagineus; the G. po/yuranodon speci­ 1864. Later, Jordan and Evermann (1902) added a men could not be located. Later, a Gymnothorax new species, Gymnothorax pescadoris, and a pindae specimen was collected in Taiwan by Ran­ new record of Thyrsoidea macrura. The former dall and McCosker (1975). Shen (1974) recorded specification, as per our description in the pre­ Rhinomuraena quaesita in southern Taiwan and sent paper is a misdesignation of Gymnothorax rectified the synonym problem between R. quaesita favagineus. Jordan and Richardson (1909) added and R. ambonensis (Shen et al. 1979). Three new 1. This is contribution no. 385 of the Institute of Zoology, Academia Sinica, ROC. 2,4. To whom reprint requests should be sent. 44 Chen et al. - Moray Eels from Taiwan 45 records which appeared in Dr. Shen's illustrated pattern of each species are provided in figures books were Strophidon brummeri (Shen 1984a), Fig. 11-1 to 11-42. Coloration was observed mostly Gymnothorax monostigmus, and Gymnomuraena on fresh specimens, formalin preserved specimens marmorata (Shen 1984b). However, his specimens were used in supplementarity. All specimens are of the former two species have not yet been located now deposited at the Museum of the Institute of and the last species, per its specimen photo, was Zoology, Academia Sinica (ASIZP), and the Na­ misidentified. As for the two new records of morays tional Marine Science Museum (NMSMP). The added by Lee (1980): Anarchias allardicei and authors have also examined the specimens Enchelynassa canina, the specimen photo of the deposited in the Museum of the Department of former species should be identified as Gymnothorax Zoology, National Taiwan University (NTUM), the chilospilus, its existence was confirmed by E. Holm Museum of the Department of Biology, Tunghai (pers. comm.); the latter identification should be University (THUP), the Taiwan Fisheries Research Enchelycore schismatorhynchus. Institute (TFRI), and the Taiwan Museum (TMF). The Lee and Tzeng (1985) new record of G. chlamydatus from Yen-Liao is valid. Chen and Yu (1986) added the nine moray species of: Echidna RESULTS AND DISCUSSION delicatula, Gymnothorax schismatorhynchus, G. petelli, G. ruppelli, G. ricnsrdsoni, G. buroensis, Key to the subfamilies and genera G. hepatica, Aemasia lichenosa, and Enchelynassa of Muraenidae in Taiwan canina in their synopsis, all questionable since no 1a. Dorsal and anal fin origin restricted to tail tip; hypobran- specimens were offered or literature cited. Recent­ chial 1 and 2 present (subfamily Uropterygiinae) 2 ly, Sasaki and Amaoka (1991) described a new 1b. Dorsal fin origin before or near gill opening; anal fin moray species, Gymnothorax prolatus, collected origin just behind anus; hypobranchial absent (subfamily from Su-ao, also invalid because their single speci­ Muraeninae) 3 2a. A lateral line pore near each posterior nostril, the pore men is a Strophidon sathete Youth (Chen and and nostril separated only by a septum Anarchias Shao, in preparation). Table 1 summarizes the 2b. No pore near posterior nostril Uropterygius taxonomic history and corrections of moray species 3a. Body elongate, TL greater than 30 4 used in several major Taiwan publications. 3b. Body stout, TL less than 30 5 In sum, 8 genera and 40 species have been 4a. Anterior nostrils not simple tubes, modified with flaps or leaflike enlargements except juvenile Rhinomuraena previously reported; but, only 4 genera and 23 4b. Anterior nostril simple tubes Strophidon species are valid. The remaining 17 species were 5a. Snout blunt, teeth shorter or conical............... 6 misidentified, synonymous, or lacked specimens. 5b. Snout longer, fang-like teeth, never molariform 8 In this paper we catalogue 9 genera and 42 moray 6a. Anus notably behind middle of body ..... Gymnomuraena species. Among which, 12 species are the first 6b. Anus close to middle or before middle of body......... 7 7a. Molariform teeth, more than 2 rows of teeth on vomer Taiwan records and the specimens of 7 other (adult) Echidna previously reported species are the first collected 7b. Conical teeth, 2 rows of low, conical teeth on vomer ..... from Taiwan. Siderea 8a. Jaws elongate and significantly curved, cannot close com- pletely, most jaw teeth protrude from the side . ................................................................... Enchelycore MATERIALS AND METHODS 8b. Jaws slightly or not curved, can close completely; most jaw teeth do not protrude from the side .... Gymnothorax Most specimens were collected by long-lining, hand-lining, trapping, or bottom trawling from the Subfamily Muraeninae Taiwan area sea bottom; several species, especial­ Genus Echidna Forster 1777 ly young fishes, living in the coral reef area were collected from tidal pools by hand-net or from sub­ Echidna Forster 1777: 81 (not seen). Type: E. variegata Forster tidal zones by SCUBA diving. Specimens were in Lichtenstein 1844 (not seen). photographed when fresh and preserved in 10% Key to species of Genus Echidna formalin for further observations. All counts and measurements were done in accordance with those 1a. Body ground whitish with 25-30 wide black rings as youth; used by Bohlke et al. (1989). The following ab­ adults mottled with little black or dark brown spots be- tween rings E. polyzona breviations are used in the text: TL, total length; 1b. Body milky yellow with numerous small black spots or HL, head length; DGO, depth of gill opening; TR, lines; 2 separate series of large starlike patches on the trunk length; Vert, number of vertebrae. Dentition back and lower half of the body E. nebulose Table 1. Taxonomic history of all species of moray eels in Taiwan with the corrections of some species names which were used mistakenly in several major taxonomic literatures of Taiwan Genus No. Species names Chinese name Chen & Weng, 1967 Shen, 1984b Chen & Yu, 1986 Other publications Echidna 1 E. nebulosa 't1l!H["it + +; x E. polyzona + 2 E. polyzona ¥ J.R~jl.JbJ? + x Gymnothorax chilospilus + Enchelycore "3 E. bikiniensis ;t-tJt, Zj 'm~it 4 E. lichenosa ,; Iil Zj ,m.'it @? (Aemasia lichenosa) 5 E. pardalis fJ Ii:.Zj ,m.'it + (Muraena pardalis) + (Muraena pardalis) + (Muraena pardalis) 6 E. schismatorhynchus w.oiryZjoiry .•it @? Enchelynassa canina x Lee, 1980Enchelynassa canina Gymnomuraena 7 G. zebra ro.,%i-)jt,@¥- (Echidna zebra) + (Echidna zebra) Gymnothorax 8 G. berndti ~l JI\ f\,AJIln;lJ .•it + + "9 G. brunneus j!»ofJIln"J.it 10 G. buroensis 1•.i1'.·Nr~JIln;lJ.•it @? 11 G. chilospilus 1f.H..:t¥.JJ&].It¥- + + + Gunther, 1870 12 G. chlamydatus .'J'.J.RofJIln~ .it + Lee & Tzeng, 1985 13 G. eurostus ill.!t ofJIln"J'it +; x Gymnothorax leucostigmus 14 G. favagineus .'12.lilofJlln"J.'it +; (G. melanospilus) +; (G. melanospilus) Jordan & Evermann, 1902:(G. pescadoris) G. favagineus .'12.lilofJlln"J .•it (G. pescadoris) (G. pescadoris) t:;J 15 G. fimbriatus ,{:."'I;ofJIln"JM + + + 0 16 G. flavimarginatus ~i!."'ofJIln"J·it + x Uropterygius marmoratus + 0- 17 G. hepaticus toi!ofJIln».<lit x Enchelycore bikiniensis @? ~. "18 G. javanicus JI\.'1:ofJIln"J.'it ~ 19 G. kidako ~Udlln"J.·it + + en 20 G. leucostigmus Eo lilofJlln"J"it + + + Jordan & Richardson, 1909 ~ l,Hfi ofJIln"J ~it 9-: "21 G. margaritophorus (I) "22 G.