Japan. J. Ichthyol. 魚 類 学 雑 誌 42(1): 39-43, 1995 42(1): 39-43, 1995

Neolamprologus longicaudatus, a New Fish from the Zairean Coast of

Kazuhiro Nakaya1 and Masta Mukwaya Gashagaza2

Laboratory of Marine Zoology, Faculty of Fisheries, Hokkaido1 University, 3-1-1 Minato-cho, Hakodate, Hokkaido 041, Japan 2Centre de Recherche en Hydrobiologie , Uvira, Zaire, B.P. 254, Bujumbura, Burundi

(Received September 9, 1994; in revised form February 10, 1995; accepted March 17, 1995)

Abstract A new cichlid, longicaudatus sp. nov. is described , based on three specimens from the north Zairean coast of Lake Tanganyika. Although similar to N. furcifer, N. christyi and N. buescheri in having an elongate body, strongly emarginate caudal fin, and vertical fins partly covered with scales, this species is distinguishable from them by its small orbit, light grayish-brown coloration of body, dorsal fin lacking a submarginal dark band, 37 longitudinal body scales, 8 gill rakers on lower limb of the 1st gill arch, and a long pointed snout.

Neolamprologus is a of the family Cichlidae Neolamprologus longicaudatus sp. nov. in Lake Tanganyika, one of the Great Rift Valley (Figs. 1, 2) lakes in the central east Africa. Lake Tanganyika is famous for its remarkable endemism seen in the Neolamprologussp. "Kavalla" Konings and Dieckhof ,f cichlid fishes, and the genus Neolamprologus is also 1992:150, fig. (Milima Island, Zair e) . endemic to the lake. Neolamprologus is the largest Holotype. HUMZ (Laboratory of Marine Zoolog y , genus among Lake Tanganyikan , and 42 Faculty of Fisheries, Hokkaido University) 12767 0 , species are presently known from the lake (Biischer, 85.5mm in standard length (SL), Cape Banza, Ubwar i 1991, 1992a, 1992b, 1993; Marechal and Poll, 1991). Peninsula,Zaire, 15m depth, gill net, Sept. 30, 199 3 . Some of these species are widely distributed through- Paratypes. CRHU (Centre de Recherche en Hydr o- out the lake, but many species have been reported biologie,Uvira, Zaire) 1993.0001, 82.3mm SL, same dat a as holotype; HUMZ 127692,69.0 mm SL, Cape Banza, from limited areas, suggesting localized geographical Ubwari Peninsula, Zaire, 12m depth, gill net, Sept. 29, distributions. 1993. The genus Neolamprologus is characterized by less than 60 longitudinal ctenoid scales on the body, the Diagnosis. This new species is distinguishable 1st soft ray of pelvic fin being longest, 18-20 dorsal from other species of the genus by the following fin spines, 5-7 anal fin spines, 6-8 canine teeth on the combination of characters: generally light grayish upper jaw, and conical inner teeth on both jaws brown body, without conspicuous markings: whitish (Poll, 1986). ventral surface of head and thoracic region: vertical During a scientific expedition to the Ubwari Pe- fins with many small dark brownish spots: elongate ninsula on the northern Zairean coast, one of the body (depth 3.57-3.89 times in standard length): authors (MMG) collected specimens of an un- long pointed snout (length 2.5-3 in head length): 8 described species of Neolamprologus from depths of gill rakers on lower limb of 1st gill arch: 37 longi- 12-15 m. It is here described as Neolamprologus tudinal scales on body: dorsal and anal fin bases longicaudatus sp. nov. partly covered by scales: strongly emarginate caudal Methods of counts and measurements mainly fol- fin, with filamentous upper and lower principal rays. lowed Hubbs and Lagler (1958), and counts of dorsal and anal fin rays were those of Trewavas Description. Counts and measurements are (1983). shown in Table 1. Body elongate; depth less than

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Fig. 1. Holotype of Neolamprologus longicaudatus sp. nov. from Cape Banza, Ubwari Peninsula, Zaire. HUMZ 127670, 85.5mm SL. This photograph was taken two days after preservation in formalin. Scale bar indicates 10mm. (Photograph by Tetsumi Takahashi).

Fig. 2. Holotype of Neolamprologus longicaudatus sp. nov. HUMZ 127670, 85.5mm SL. Scale bar indicates 10mm. head length, highest at occiput in holotype and larger Pectoral fin extending a little beyond anus. First paratype specimens. Dorsal profile of head almost pelvic soft ray longest, extending beyond anal origin straight, but slightly concave above eye in holotype to 3rd anal fin spine base. Caudal fin strongly and larger paratype. Occiput swollen in larger spec- emarginate, upper- and lower-most principal rays imens. Snout long and pointed; length larger than extremely elongated and filamentous. eye diameter, nearly 2 times in larger specimens, 1.2 Four canine teeth present anteriorly on upper and times in smaller paratype. Interorbital region broad- lower jaws, outer two teeth larger; a single series of ly rounded. Mouth terminal, lower jaw projecting large conical teeth along outer side of jaws; inner slightly beyond upper jaw; upper jaw not reaching teeth small, conical, in many rows. level of anterior margin of eye in larger specimens, Scales on body weakly ctenoid, smaller and rather extending beyond level in smaller paratype. Eye irregular in arrangement between upper lateral line relatively small. Suborbital narrow, width much less and spinous dorsal fin base. Cheek with very few than eye diameter. scales. Opercle scaly. Nape naked, occiput with Dorsal fin larger posteriorly, 1st dorsal spine very many small scales. Thoracic region scaled at pecto- short, spine length progressively increasing poste- ral and pelvic bases, naked between. Soft dorsal fin, riorly to 6th or 7th spines, 5th soft ray extending to posterior part of spinous dorsal fin, and anal fin middle of caudal fin. Anal fin spines longer poste- scaled at bases. Caudal fin scaled nearly to posterior riorly, 4th soft ray extending to middle of caudal fin. margin of the fin.

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Gill rakers short, stout. valla Islands). In depths exceeding 12m. Color in alcohol. -Ground color of head and body light brownish or light grayish-brown. Snout, upper Etymology. The species name, longicaudatus, is jaw and dorsal surface of head darker. Lower jaw, derived from the Latin longi for long and caudatus lower part of opercular region, branchiostegal mem- for tail, in reference to having a very long filamen- brane and thoracic region whitish. Dorsal fin and tous caudal fin. upper half of caudal fin paler than anal fin and lower half of caudal fin. Dorsal fin membrane blackish Remarks. The present new species conforms well marginally. Dorsal, anal and caudal fins with many to the definition of Neolamprologus given by Poll small dark brownish spots. Pelvic fin dark, but the (1986), except for the number of canine teeth on the longest 1st soft ray whitish. upper jaw. The type specimens have 4 canine teeth on the upper jaw, whereas Poll (1986) considered Distribution. Lake Tanganyika along north and Neolamprologus as having 6-8 canine teeth. How- middle Zairean coast (Fig. 3, Cape Banza and Ka- ever, the teeth are more variable within the genus,

Table 1. Counts and measurements of Neolamprologus longicaudatus sp. nov. from Lake Tanganyika

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Konings and Dieckhoff (1992: 150) gave a photo- graph of present new species, taken at Milima Island, Zaire.

Acknowledgments

We express our sincere thanks to Professor Hiroya Kawanabe, Kyoto University, Professor Kunio Amaoka, Hokkaido University and Assoc. Professor Yasunobu Yanagisawa, Ehime University, for giving us an opportunity to make taxonomic researches on the fishes of Lake Tanganyika. Mr. Tetsumi Taka- hashi, Hokkaido University, helped us in various ways, and Mr. Christian O. Nyako, Hokkaido Uni- versity, read the English manuscript. This study was partly supported by a Grant-in-Aid for Overseas Scientific Survey (No. 4041078) from the Ministry of Education, Science and Culture, Japan. Fig. 3. Northern part of Lake Tanganyika, show- ing type locality and known distribution of Neo- longicaudatus sp. nov. Literature Cited and according to our unpublished data, for example, Boulenger,G.A. 1898. Report on the collectionof fish e s some specimens of Neolamprologus toae have 10 made by Mr. J.E.S. Moore in Lake Tanganyikaduri n g canine teeth. As all the other characters of present his expedition, 1895-96. Trans. Zool. Soc. London, 15 : new species are clearly those of Neolamprologus, this 1-30 . difference in number of canine teeth is not important Biischer, H.H. 1991. Ein neuer tanganjikasee-Cichlid e for generic assignment. aus Zaire. Neolamprologuspectoralis n. sp. (Cichlidae , Neolamprologus longicaudatus sp. nov. is charac- ). Die Aquarien-und Terrarienzeitschri ft terized by an elongate body, partly-scaled bases of (DATZ), 44:788-7 92 . the dorsal and anal fins, and a strongly emarginate Buscher, H.H. 1992a. Ein neuer Cichlideaus dem Ta n- caudal fin with filamentous upper and lower principal ganjikasee. n. sp. Die Aquarien - und Terrarienzeitschrift(DATZ), 45: 520-52 5 . rays. Such features are also characteristic of N. Biischer,H.H. 1992b. Neolamprologusnigriventris n. sp. : furcifer (Boulenger, 1898), N. christyi (Trewavas Ein neuer Tanganjikasee-Cichlide(Cichlidae, Lampro l - and Poll, 1952) and N. buescheri (Staeck, 1983). ogini). Die Aquarien-und Terrarienzeitschrift(DATZ ) , However, this new species can be easily distinguished 45: 778-78 2 . from N. furcifer by its small orbit, length of which is Biischer,H. H. 1993.Neolamprologus bifasciatus n. sp.: Ei n much shorter than snout length (almost equal in N. neuer Tanganjikasee-Cichlide(Cichlidae, Lamprolog - furcifer), broader interorbital which is equal to or ini). Die Aquarien- und Terrarienzeitschrift(DAT Z ) , larger than eye diameter (much less), lighter body 46: 385-38 9 . coloration (dark), and 8 gill rakers on the lower limb Hubbs, C.L. and K.F. Lagler. 1958. Fishes of the Grea t of 1st gill arch (16 gill rakers) (Boulenger, 1898). It Lakes region. Bull. Cranbrook Inst. Sci., 26: 1-213 . Konings, A. and H.W. Dieckhoff. 1992. Tanganyik a is distinguishable from N. christyi by having 37 longi- secrets. CichlidPress, St. Leon Rot, Germany. 207 pp . tudinal body scales (50-60 scales in N. christyi), and Marechal, C. and M. Poll. 1991. Neolamprologus.Pag e s a more pointed snout (obtuse) (Trewavas and Poll, 274-294 in J. Daget, J.-P. Gosse, G. G. Teugels and D. 1952). N. buescheri has a conspicuous broad, black, F.E. Thys van den Audenaerde, eds. Checklist of t he submarginal longitudinal band along the dorsal fin freshwater fishesof Africa (CLOFFA). Volume 4. Inst i- (Staeck, 1983: 327), but present new species lacks tut Royal des SciencesNaturelles de Belgique,Bruxell e s . such a submarginal band on the fin. Poll, M. 1986. Classificationdes Cichlidae du lac Ta n-

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ganika. Tribus, genres et especes. Acad. Roy. Belgium., ア フ リカ ・タ ンガ ニ ー 力湖 の 北 部 ザ イ ー ル沿 岸 か ら採 集 Mem. Classe Sci., 45: 1-163. さ れ た カ ワ ス ズ メ 科 の1新 種 Neolamprologus longi- Staeck, W. 1983. Lamprologus buescheri n. sp. from the caudatus Zambian part of Lake Tanganyika. Senckenbergiana 仲 谷 一 宏 ・Masta Mukwaya Gashagaza Biol., 63: 325-328.

Trewavas, E. 1983. Tilapiine fishes of the genera Sarothero- ア フ リカ ・ タ ン ガ ニ ー カ 湖 の ザ イ ー ル 国 北 部 に位 置 す る ウ don, Oreochromis and Danakilia. British Museum (Nat- ブ ァ リ半 島 先 端 よ り採 集 され た3個 体 の標 本 に基 づ い て,カ ワ ural History), London. ix+583 pp. ス ズ メ科 の新 種 Neolamprologus longicaudatus を記 載 した.本 種 Trewavas, E. and M. Poll. 1952. Three new species and は体 が細 長 く,尾 鰭 が 湾入 し,さ らに上 下 の主 鰭 条 が 延 長 す る な two new subspecies of the genus Lamprologus, cichlid どの特徴 で N. furcifer, N. christyi お よ び N. buescheri に似 る が, fishes of Lake Tanganyika. Bull. Inst. Roy. Sci. Nat. 体 が ほ ぼ一 様 な灰 褐 色 で,背 鰭,臀 鰭 お よ び尾 鰭 に黒 褐 色 の小 斑 Belgique, 28: 1-16. 点 が並 ぶ こ と,頭 部 腹 面 が 白 い こ と,背 鰭 の縁 辺 近 くに黒 色 線 が な い こ と,縦 列 鱗 数 が37枚 で あ る こ と,第1鰓 弓 の下 枝 鰓 耙 数 が8本 で あ る こ と,吻 が 尖 る こ とな どで これ ら3種 と識 別 さ れ る.

(仲谷:〒041函 館 市 港 町3-1-1北 海 道 大 学 水 産 学 部 水 産 動 物 学 講 座;Gashagaza:ザ イ ー ル水 圏 生 物 学 研 究 セ ン ター)

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