TWO NEW GENERA OF LOACHES (PISCES: COBITIDAE: COBITINAE) FROM KOREA

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1 Trav. Mus. natl. Hist. nat. ~Grigore Antipam Vol. XXXIX pp D6cembre 1997 TWO NEW GENERA OF LOACHES (PISCES: COBITIDAE: COBITINAE) FROM KOREA IK SO0 KIM. JONG YOUNG PARK, TEODOR T. NALBANT On dccrit deux nouveaux genres: Koreocobitis (type: Cobitis rotundicaudata Wakya et Mori, 1929) et Choia (type: Niwaklla brevifasciata Kim et Lee, 1995). Le premier genre a une forme qui ressemble aux espkces de Misgurnus, mais il a 1'Cpine suborbitale grande et fonctionelle. Le second genre ressemble en apparence?i Niwa?ila, mais il a 4 rayons mous dans l'anale, de longues moustaches et des levres infkrieurs bien individualiscs et pontus. The systematic position of the loaches of Korea is now in a process of understanding. This is due to the apart place occupied by Korean Peninsula and its riverine system among the hydrographic network of mainland Asia and Japanese great islands. This apart character of Korean freshwater ichthyofauna is well expressed by the loach-like fishes, Cobitinae. For instance two genera, Iksookimia and Niwaella are regional endemic, the former in Korean hydrographic network and Amur drainage, the latter in Korea and Japanese greatest island, Honsu. In the present contribution, we are separating two new genera, formerly considered as Cobitis and Niwaella. This separation gives a new aspect in the phylogeny and zoogeography of Cobitinae loaches, especially for Korean forms. Koreocobitis new genus Type species: Cobitis rotundicaudata Wakya and Mori, 1929 Etymology from Korea, the name of the country in wich this loach is living and Cobitis the name of a well known loach. Gender feminine. Diagnose: a loach very similar in shape and size with Misgurnus but differing from it in the presence of a movable suborbitar spine, scales with a large and nearly central focal zone and reduced mental lobes, not forming barbell like projection.

2 192 1K SO0 KIM. JONG YOUNG PARK, TEODOR T. NALBANT Description. Fin rary formula: D , A , VI 6, PI 8-9. Size as adults: up to 160 mm SL. Body elongate, cilindrical just behind the head but well compressed in the rest of its lenght. Head normal in size, compressed enough with small eyes generally placed in its mid-part or slightly before. Mouth inferior, slightly arched with thickened lips well furrowed. Barbels three pairs, one rostral, one maxillary and one maxillo-mandibular. Mental lobes well developed with a short prolongation at their tips. Suborbital spine movable, relatively small slightly curved (in rotundicaudata) or straight (in a new species not yet described). Dorsal fin placed slightly in the second half of body on the same line of insertion with the ventral fins. Distal edge of the dorsal convex. Caudal fin with rouded margin (in rotundicaudata) or truncate (in the new species). Sexual dimorphism: in both species the males have at the base of second ray of pectorals a laminar process more or less squarrish (Canestrini's scale or lamina circularis). Scales cover the whole body except the head and its sides. They are slightly rounded with a large and nearly central focal zone. Lateral line very short marked by a few neuromast pits just behind the head. Colour variable, above olive, below yellow to orange with dark-gray punctuation from the head to the tail especially on back or mottled with dark-gray markings. Generally there is a white median band on the head, faded in rotundicaudata. Range: till now reported only in Korean rivers. Species: two, rotundicaudata and one undescribed. Concerning the former species the syntypes are lost now. A neotype was selected (CNUC, one adult male 81.0 mm SL) from near the original type locality (according to Wakya and Mori, 1929: 33, the South Han river at Tanyo). The locality of the new type series is: Korea: Youm hyon stream, tributary of South Han river, Shingok-ri, Yonsangchon-myon, Dangyang-gun, Chung-chonbuk-do, July 9,1996, Kim, Park, Kim and Nalbant coll. For other data concerning Koreocobitis rotundicaudata see Kim, Choia new genus Type species: Niwaella brevifasciata Kim and Lee, Etymology the name of this genus was given in honour of Prof. Dr Ki Chul Choi, who contributed very much in the study of Korean freshwater fishes. Gender feminine.

3 TWO NEW GENERA OF LOACHES (PISCES) FROM KOREA 193 Diagnose: a loach very similar with Niwaella but differ essentially from it in having only 4 branched rays in anal fin and well developed barbels and mental lobes. Description: fin rays formula: DIII 6, A111 4, VI 4-5, PI 7. Size as adult, mm SL. Body elongate, compressed. Head relatively small. Eyes amall placed nearly in the middle of head or slightly before. Mouth not arched, nearly straight with well developed lips covered with small button-like formation. Barbels three pairs, one rostral, one maxillary and one maxillo-mandibular. Mental lobes well developed, pointed. Suborbital spine relatively small, movable with two thorns. Dorsal fin placed in the second half of body on the same line of insertion with ventral fins. Both dorsal and caudal fins margins rounded. Sexual dimorphism absent but the males seem to be smaller than the females. Scales cover whole body excepting the head and its sides. They are oval with a large focal zone. Lateral line very short, not exceedings the lenght of pectoral fins. Colour based on dark-gray dorsal median blotches. Another row of vertical blotches, same colour, is placed along the mid-side of the body. Between these two rows there is a row of small mottled grayish dots. A black round dot is situated in the upper part of the base of caudal fin. Range: until now Choia brevifasciata was found in a few small rivers in the extreme south part of Korean Peninsula (see Kim and Lee, 1995: 287). Remarks: The presence of 4 branched rays in anal fin is an unusual character in Cobitidae. Accidentally in different genera these are some specimens with 4 and even 3 branched rays in this fin but it is an exception or more probably an anomaly. However, Yang, Chen and Lan, 1994: 93, reported for their Protocobitis typhlops from south-east China, in a cave lake, a few specimens with 4 and half branched rays in anal fin. Of course, Choia brevifasciata is the sister lineage of the genus Niwaella with one species in Korea and one species in Honsu island, Japan. The reduction of the branched rays in anal fin represent an apomorphy (or an autapomorphy?). However, the colour pattern of Choia resambles with those of some species (koreensis, pumila) of the genus Iksookimia. In our opinion concerning this character Choia represent a plesiomarphic condition. Another plesiomorphy is the normal development of barbels and mental lobes. Abbreviations: CNUC = Chonbuk National University, Chonju

Kim, Park, Kim and Nalbant coll., 81.0 mm SL. B. Mouth of neotype. C. Suborbital spine of 90.3 mm SL specimen. D. Lamina circularis of a 91.2 mm SL specimen. E.

4 194 IK SO0 KIM. JONG YOUNG PARK. TEODOR T. NALBANT Fig. 1 - Koreocobitis rotundicaudata (Wakya and Mori, 1929) A. The neotype specimen from: South Korea: Simgok-ri (stream), South Han river basin, Yosangchon-myon, Dangyang-gun. Chungchongbuk-do, July 9, Kim, Park, Kim and Nalbant coll., 81.0 mm SL. B. Mouth of neotype. C. Suborbital spine of 90.3 mm SL specimen. D. Lamina circularis of a 91.2 mm SL specimen. E. Subdorsal scale of the neotype. Fig. 2 - Choia brevifasciata (Kim and Lee, 1995) A. Holotype CNUC 19907, adult male 41.9 mm SL. South Korea: Koup stream, Kohung Peninsula. B. Mouth of a paratype specimens. (Both figures from Kim and Lee, 1995: 286).

5 TWO NEW GENERA OF LOACHES (PISCES) FROM KOREA 195 DOUA NO1 GENURI DE COBITIDE (PISCES: COBITIDAE: COBITINAE) DIN COREEA REZUMAT Sunt descrise dou, genuri noi: Koreocobitis (tip: Cobitis rotundicaudata Wakya qi Mori, 1929) qi Choia (tip: Niwa2lla brevifasciata Kim si Lee, 1995). Primul gen se asearntin5 ca form2 cu speciile de Misgurnus dar la care spinul suborbitar este mare qi functional. A1 doilea gen aparent se asearntin5 cu Niwailla dar cu 4 radii divizate in anal5 qi must5ti lungi qi lobi mentali individualizafi. REFERENCES KIM. I.S Morphological characters of Korean Spinous loach, Cobitis rotundicaudata (Cobitidae. Cypriniformes). Bas.Sci.Rev., 2: (Kor. EngLAbstr.). KIM. I.S.. LEE. W.O., Niwa2lla brevifasciata a New Cobitid Fish (Cypiniformes: Cobitidae) with a Revised Key to the species of Niwa2lla. Jap.J.lchthyol., 42, 3-4: WAKYA. Y.. MORI, T., On Two New Loaches of the Genus Cobitid from Corea. J.Chosen Nat.Hist.Soc., 9: YANG. J.X., CHEN, Y.R., LAN, J.H., Protocobitis typhlops, a new genus and species of cave loach from China (Cypriniformes: Cobitidae). Ichthyol. Explor. Freshwaters. 5. 1: Received: June Accepted: July Ik Soo Kim and Jong Young Park Department of Biology, College of Na tural Sciences Chonbuk National University, Chonju, Republic of Korea (South Korea) Teodor T. Nalbant Department of Animal Taxonomy, Institute of Biological Sciences 31. Str. Frumoasg. Corp B, Bucure~ti, RO Romania

Taxonomic study of the genus Niwaella (Cypriniformes: Cobitidae) from East China, with description of four new species

Zoological Systematics, 42(4): 490 507 (October 2017), DOI: 10.11865/zs.201723 ORIGINAL ARTICLE Taxonomic study of the genus Niwaella (Cypriniformes: Cobitidae) from East China, with description of four