ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 473 A redescription of Haplochromis labriformus (Nichols & LaMonte, 1938) M.J.P. van Oijen&F. Witte Oijen, M.J.P. van & F. Witte.Aredescription of Haplochromis labriformus(Nichols & LaMonte, 1938). Zool. Med. 77 (29), 30.xii.2003: 473-479, figs 1-4.— ISSN 0024-0672. M.J.P. van Oijen, Afdeling Vertebraten (Pisces), Nationaal Natuurhistorisch Museum, Leiden, PO Box 9517, 2300 RA Leiden, The Netherlands (e-mail: oijen @naturalis.nnm.nl). F. Witte, Institute of Biology, Leiden University, P.O. Box 9516, 2300 RA, Leiden, The Netherlands (e-mail: [email protected]). Key words: Cichlidae: Haplochromis labriformus: redescription: Lake Victoria. The single cichlid fish from Lake Victoria on which Nichols & LaMonte (1938) based their new species Tilapia labriforma was re-examined. It turned out to be a haplochromine cichlid. The specimen is redescribed and compared to similar species from Lake Victoria. Introduction In 1938 J.T. Nichols and F.R. LaMonte described two new species from a small col- lection of fishes from Lake Victoria that was sent to the American Museum of Natural History in 1937. The collection was made by Michael Lerner. Nothing is known about the catch locality, the catch date or the fishing technique. One of the described species, a characid, Micralestes lerneri, was later found to be a synonym of Alestes sadleriBoulenger, 1906 (Greenwood, 1959). The other species was a cichlid, which Nichols & LaMonte described as a species of Tilapia. However, this specimen has ctenoid scales on the flank (a character mentioned in the description by Nichols & LaMonte), whereas tilapiines have cycloid scales (Trewavas, 1981). Further it lacks foramina on the ventral surface of the lower pharyngeal bone as well as a median ridge of bone at the dorsal keel of the lower pharyngeal bone (tilapiine characters defined by Stiassny, 1991). Therefore, it is not a tilapiine but a haplochromine cichlid. The species is neither mentioned in Greenwood’s revisions of the Lake Victoria Haplochromis species (many papers in Greenwood, 1981), nor in his papers on the phyletic classification of the ‘genus’ Hap- lochromis (Greenwood, 1979, 1980). As both the description and the accompanying drawing are not accurate and contain mistakes, the species is redescribed here in order to facilitate a comparison with other haplochromine species from Lake Victoria. Definitions follow Barel et al. (1977) and Witte & Witte-Maas (1981). Description Haplochromis labriformus(Nichols & LaMonte, 1938) (figs 1-4, table 1) Tilapia labriformaNichols & LaMonte, 1938: 2. Haplochromis labriformis; van Oijen et al., 1991: 135; Eschmeyer, 1998: 856. Tilapia labriformis; van Oijen, 1996; 76. ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 474 474 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) Material.— Holotype, AMNH 13738, a male, 62.0 mm SL, collected from Lake Victoria by M. Lerner in 1937. Diagnosis.— A small, moderately slender micrognathic species, with unequally bi- cuspid teeth, a single inner row in both jaws, and the caudal third part of the premaxilla edentulous. Body of the preserved specimen uniformly light brown, without markings. State of preservation (fig. 1). The specimen has the suspensoria abducted and the mouth wide open. Both pectoral fins are folded forward and some rays of the pectoral fin on the right side are damaged. In the dorsal half of the caudal fin the caudal quar- ter of rays is broken off. The gill apparatus has been cut to dissect the lower pharyn- geal element, which was found inserted below the branchial basket. The symphysis of the lower jaw is disconnnected and a rostral section of the left premaxilla is only loosely attached to the remainder of the bone. Habitus (figs 1, 2).— General body shape moderately slender. Caudal peduncle relatively broad. Dorsal head profile nearly straight. Premaxillary pedicel prominence not visible. Snout acuteness not measurable. Gape inclination not measurable. Pre- maxilla not expanded medially. Maxillary extension not measurable. Lips not thick- ened. Lateral snout outline not measurable. Because of the widely opened mouth the mental prominence is not visible, but inspection of the mental area shows there is a protuberance on the ventral side of the symphysis of the dentary. Horizontal limb of preoperculum rostrally inclining dorsad. Vertical limb dorsally inclining caudad. Cephalic lateral line openings not enlarged. Lateral line canals on lachrymal not well visible. Eye moderately large, circular. Dorsal eye margin nearly touching dorsal head profile. Pupil slightly elliptical. A small aphakic space anterior to the lens. Fins.— Pectoral fin with fourteen rays. The longest ray on the left side just reaches the vertical through the anal fin origin. First pelvic ray reaching the origin of the third anal spine. Anal fin with three spines and nine rays. Dorsal fin with fifteen spines and ten rays. Tips of dorsal and anal not reaching a vertical through the caudal fin base. Caudal fin with 22 rays. The posterior margin of the dorsal part of the fin is damaged. Judging from the ventral half of the fin margin, the outline was slightly emarginate. Fig. 1. Haplochromis labriformus (Nichols & LaMonte, 1938). Holotype, AMNH 13738, left lateral view. Scale equals 10 mm. ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 475 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) 475 As lunate caudal fins are unknown for the haplochromine cichlids of Lake Victoria, the convexity of the caudal margin in the figure of Nichols & LaMonte (1938) (see fig. 3) probably was exaggerated. Scales.— Scales on cheek, gill cover and nuchal area cycloid. On nape and dorsum the scales are cycloid up to below the sixth dorsal spine where they become weakly ctenoid. From below the tenth spine the scales are fully ctenoid. Flank, chest, belly and caudal peduncle with ctenoid scales. Chest scales smaller than scales on belly and flank, size transition gradual. Caudal fin with single rows of small, elongate ctenoid scales between the rays of the basal fourth part. More caudally, a few isolated small ctenoid scales are present between some of the dorsal and ventral rays. There are 32 lateral line scales, five scales between the lateral lin and the dorsal fin origin, five scales between the pectoral and the pelvic fin bases and three horizontal scale rows on the cheek. Gill-apparatus.— There are 14 gill rakers on the lower part of the first gill arch on the left side; the lowermost three reduced, the following one short and the following nine slender and conical. The tip of the 13th raker is slightly expanded tending to bifid. The gill rakers are relatively widely spaced, their tips not touching each other. There are ca 96 gill filaments on the first hemibranch on the left side. Oral teeth.— Shape (fig. 4). Outer row teeth are relatively short, broad, slightly curved, subequally bicuspid. The major cusp is subequilateral and has a small flange near the cusp gap. Cusp gap narrow. Minor cusp blunt. In lateral view the neck is moderately slender and the crown expanded. In lateral view neck normal, crown compressed at the tip. Some lateral teeth may be weakly bicuspid or have the minor cusp broken off. Tooth size decreases caudad. Inner row teeth are very small, weakly tricuspid or tricuspid. — Dental arcade and tooth band. Dental arcade rounded and U-shaped. The caudal third of the premaxilla is edentulous. There is one inner row in the upper jaw and one inner row in the lower jaw. The inner row in the lower jaw is slightly irregular. Fig. 2. Haplochromis labriformus (Nichols & LaMonte, 1938). Holotype, AMNH 13738. Habitus, left lateral view. Scale equals 10 mm. Drawing by M. van Oijen. ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 476 476 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) — Counts and setting. There are 14 (left)+17 (right) = 31 teeth in the outer row of the upper jaw and 16 (left)+15 (right) = 31 teeth in the outer row of the lower jaw. Outer teeth in both jaws regularly set at a distance of 1/4-3/4 times the diameter of the tooth base. Gap between outer row and inner row distinct in both jaws. Outer row in lower jaw just not reaching the base of the coronoid wing. — Implantation. Outer teeth in upper jaw erect, slightly symphysiad inclined. Inner row teeth in upper jaw slightly recumbent. Outer teeth in lower jaw slightly procum- bent, slightly symphysiad inclined. Inner row teeth in lower jaw erect. Pharyngeal teeth.— Counts. There are 40 teeth in the caudalmost row and 12 and 13 in the medial series. — Shape. Most pharyngeal teeth are of the bevelled type, fine and acutely pointed. There are a few teeth of the pronounced type in the rostral area. The teeth in the cau- dalmost row are relatively stout and blunt, of the hooked type. However, the major cusp is only slightly curved. Tooth size increases from rostral to caudal and from lateral to medial. Osteology. — Neurocranium. Judging from an X-ray photograph, the neurocranium of H. labri- formusis very similar to that of H. laparogramma (Greenwood & Gee, 1969; fig. 18) — Oral jaws. Premaxilla; dentigerous arm shorter than ascending arm. Ventral out- line of the dentigerous arm nearly straight. Mandible slender. Length/ depth ratio 2.3. Length of the tooth bearing part is 1/3 of the jaw length. (Measurements taken from X-ray photograph). — Lower pharyngeal element. Lower pharyngeal element rather shallow, slightly longer than broad. Dentigerous area slightly broader than long. — Vertebrae. There are 30 vertebrae, comprising 13 abdominal and 17 caudal ele- ments. Viscera.— No information is available on the configuration of the intestines. Fig. 3. Haplchromis labriformus (Nichols & LaMonte, 1938). Holotype, AMNH 13738. Habitus, from Nichols & LaMonte (1938). ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 477 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) 477 Gonads.— The testis of the specimen are in an advanced stage of development (stage IV, see Mous et al., 1995: 74). Males with testis in this stage of development nor- mally have the pelvic fins blackish. In this specimen there are only few traces of pig- ment cells on the membrane between the first and second ray. Colouration.— There are no data available on the live colouration of the specimen. — Preserved colouration. The specimen is uniformly light brownish except for faint remains of an opercular blotch. Distribution.— H. labriformusis only known from Lake Victoria. Catch locality.— Apparently the only information accompanying the specimen when it was presented to the American Museum of Natural History was that it was caught in Lake Victoria. Remarks on the original drawing In the original drawing (fig. 3) the mouth is closed, the premaxilla is slightly pro- truded, the mouth bottom is depressed and the branchiostechal rays seem abducted. As at present (figs 1, 2) the specimen has the mouth wide open, the suspensoria abducted and the premaxillae maximally protruded, it is likely that the mouth was artificially closed for the first drawing. Therefore, the shape of the rostral part of the head, including the gape inclination and the snout acuteness in that drawing are arti- ficial. There are more inaccuracies in the original drawing. The convexity of the caudal margin of the caudal fin is exaggerated: in reality it is not lunate, but emarginate. The tips of the dorsal and anal fins do not reach the caudal fin origin. The length and shape of various fin spines and rays are inaccurate. The number of pectoral, dorsal and anal rays is inaccurate. Size and position of many scales are erroneous. Especially those on the chest, which are smaller than the other ones on the ventral side. The area of the opercular blotch is drawn too large. As the fish now is uniformly brownish, shading has not been applied to the new habitus figure (fig. 2). a Comparison of H. labriformus with similar species from Lake Victoria As the specimen of H. labriformus is a male and has a relatively large eden- tulous caudal part at the premaxilla, it resembles species of the laparogramma group (Witte & Witte-Maas, 1987). The b c specimen was compared to similar sized Fig. 4. Haplochromis labriformus (Nichols & La- males of three species of the laparogram- Monte, 1938). Holotype AMNH 13738. Distal part magroup, viz.: Haplochromis laparogram- of outer row teeth, rostral view. a. Rostralmost ma Greenwood & Gee, 1969, H. heu- teeth of left premaxilla. b. Rostralmost teeth of right sinkveldi Witte & Witte-Maas, 1987 and mandible. c. Second medial tooth of left mandible. H. pyrrhocephalus Witte & Witte-Maas, Scale equals 1 mm. ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 478 478 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) 1987. Moreover, it was compared with specimens of H. piceatus Greenwood & Gee, 1969, as this species resembles the species of the laparogrammagroup (Witte and Witte- Maas, 1987). For the comparison with H. piceatus and H. laparogramma, specimens from the north and the south side of the Lake were used. H. labriformusdiffers from the three species of the laparogrammagroup as it has only one inner row in both jaws, whereas the others all have a short second row in the lower jaw and usually a complete second inner row in the upper jaw. H. piceatus has two, rarely three inner rows in the upper jaw and one or two inner rows in the lower jaw. Comparison of morphometric measurements revealed that the holotype of H. labri- formus differs from H.laparogramma, H. pyrrhocephalus, H. heusinkveldiand H. piceatusby having a shorter caudal peduncle and a shallower cheek. The most obvious difference with H. laparogrammalies in the mid lateral band, which is lacking in H. labriformus. Compared to H. heusinkveldi, H. labriformus has also a relatively deeper body, a shallower caudal peduncle, a longer snout, a larger head width and smaller teeth. H. labriformesdiffers from H.laparogrammaand H.heusinkveldibecause the dorsal outline of the dorsum meets the dorsal outline of the caudal peduncle in an angle, whereas in the other species this transition is smooth. Compared to H. pyrrocephalus H. labriformus also has a longer snout, a larger head width, a smaller eye and a shorter lower jaw. In H. pyrrhocepalusthe fins have a much lighter colour than the body. The outer teeth and the flange of their major cusps in H. labriformus are slightly smaller compared to those in H. pyrrhocephalus. Compared to H. piceatus,H. labriformusalso has a slightly shorter head. MoreoverH. labriformusdiffers from all above mentioned species in having the gill rakers on the first gill arch more widely spaced. Affinities with the genus YssichromisGreenwood, 1980 Following the guide to the identification of haplochromine genera in Lakes Victoria, Kioga, Nabugabo, Edward, George and Kivu (in Greenwood, 1980), the dental charac- ters of Haplochromis labriformus place it near Yssichromis. Although, its body depth of 31.5% SL falls outside the range of 23-30% given for that genus, Witte and Witte-Maas (1987) already stated that on the basis of data in Greenwood and Gee (1969) the range should at least be stretched to 31.1%, while their new species H. pyrrhocephalus, a cer- tain member of the laparogramma group, would extend the range to 34%. Caudal peduncle length and caudal peduncle length/depth of H. labriformus fall in the range of Yssichromisas given in Greenwood (1980). However, for reasons given in van Oijen (1996) we prefer to place this species in Haplochromis. Conclusion The single specimen of Haplochromis labriformusclosely resembles specimens of the H.laparogrammagroup (Witte & Witte-Maas, 1987) and H. piceatus. H. labriformushas a relatively smaller cheek depth and differs in the number of inner rows and slight dif- ferences in tooth shape. The observed differences in preserved colouration may become less distinct over the years. As the catch locality of the specimen is unknown and the species composition of Lake Victoria has altered drastically since the upsurge of the Nile Perch, it is doubtful if additional specimens of this species will ever be recog- ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 479 van Oijen & Witte.Redescription of Haplochromis labriformus. Zool. Med. Leiden 77 (2003) 479 nised as such. This paper may well be the last attempt to save H. labriformus at least temporarily from oblivion. Acknowledgements We are indebted to the staff of the Department of Ichthyology of the American Museum of Natural History, New York, for sending the type of Tilapia labriformuson loan. We thank Peter Snelderwaard, Van der Klaauw laboratory, Leiden, for the Xray photographs and Bernardo Guillen for the photo of the specimen. References Barel, C.D.N., M.J.P. van Oijen, F. Witte & E.L.M. Witte-Maas, 1977. An introduction to the taxonomy and morphology of the haplochromine cichlids of LakeVictoria.— Neth. J. Zool. 27: 333-389. Eschmeyer, W.N. (ed.), 1998. Catalog of Fishes 1: 1-958.— San Francisco. Greenwood, P.H., 1959. The characin fishes of lakes Victoria and Kioga.— Ann. Mag. nat. Hist. 2 (13): 41-47. Greenwood, P.H., 1979. Towards a phyletic classification of the “genus” Haplochromisand related taxa. Part I.— Bull. Br. Mus. nat. Hist. Zool. 35 (1): 265-322. Greenwood, P.H., 1980. Towards a phyletic classification of the “genus” Haplochromisand related taxa. Part II: the species from Lakes Victoria, Nabugabo, Edward, George and Kivu.— Bull. Br. Mus. nat. Hist. Zool. 39 (1): 1-110. Greenwood, P.H., 1981. The Haplochromine Fishes of the East African Lakes.— München. Greenwood, P.H. & J.M. Gee, 1969. A revision of the Lake Victoria Haplochromisspecies (Pisces, Cichli- dae), Part VII.— Bull. Br. Mus. nat. Hist. Zool. 18 (1): 1-65. Nichols, J.T. & F.R. LaMonte, 1938. Two new fishes from Lake Victoria.— Am. Mus. Novit. 1001: 1-3. Mous, P.J., P.C. Goudswaard, E.F.B. Katunzi, Y.L. Budeba, F. Witte & W. Ligtvoet, 1995. Sampling and Measuring. In: Witte, F. & W.L.T. van Densen (eds). Fish Stocks and Fisheries of Lake Victoria. A handbook for field observations: 55-82.— Cardigan, U.K. Oijen, M.J.P. van, J. Snoeks, P.H.Skelton, C. Marchal & G.G. Teugels, 1991. Haplochromis(pp 100-184). In: Daget, J., J.P. Gosse, G.G.Teugels & D.F.E. Thys van den Audenaerde (eds). Check-List of the Freshwater Fishes of Africa. CLOFFA, 4: 100-184.— Bruxelles.. Oijen, M.J.P. van, 1996. The generic classification of haplochromine cichlids of lake Victoria, East Africa.— Zool. Verh., Leiden 302: 57-110. Stiassny, M.L.J., 1991. Phylogenetic interrelationships of the family Cichlidae: an overview. In: M.H.A. Keenleyside (ed.). Cichlid Fishes. Behaviour, ecology and evolution: 1-35.— London. Trewavas, E.T., 1983. Tilapiine fishes of the genera Sarotherodon, Oreochromis and Danikilia.— London (British Museum (Natural History)). Witte, F. & E.L.M. Witte-Maas, 1981. Haplochromine cleaner-fishes: a taxonomic and eco-morphological description of two new species.– Neth. J. Zool. 31 (1): 203-231. Witte, F. & E.L.M. Witte-Maas, 1987. Implications for taxonomy and functional morphology of intra- specific variation in haplochromine cichlids of Lake Victoria. With descriptions of five zooplankti- vorous species. InWitte, 1987. From form to fishery. An ecological and taxonomical contribution to morphology and fishery of Lake Victoria cichlids: Chapter 2.— Thesis, Rijksuniversiteit Leiden. Received: 24.vi.2003 Accepted: 5.x.2003 Edited: C. van Achterberg ZM077 473-480 | oijen29 15-01-2007 09:30 Pagina 480