PROC. BIOL. SOC. WASH. 94(4), 1981, pp. 1076-1084 NANNOCHARAX MACULICAUDA, A NEW SPECIES OF AFRICAN CHARACOID FISH (CHARACOIDEA: DISTICHODONTIDAE) WITH COMMENTS ON THE GENUS HEMIGRAMMOCHARAX Richard P. Vari and Jacques Gery Abstract. — A new species of African characoid of the genus Nannochar-ax is described from the upper Ivindo River system of Gabon. The high longitudinal scale count, elongate body form, and absence of marked head and body pigmentation other than a prominent caudal peduncle spot distin-guish this species within the monophyletic assemblage formed by Nanno-charax and Hemigrammocharax within the Distichodontidae. The validity of the currently used diagnostic character for Hemigrammocharax is dis-cussed. Introduction As discussed by Vari (1979:332) the phylogenetic relationships within the monophyletic assemblage formed by Nannocharax and Hemigrammochar-ax of the Distichodontidae remain unresolved. The current distinction be-tween these genera is based solely on the extent of the pored lateral line, a character of questionable validity both diagnostically and phylogenetical-ly. Nonetheless, given the absence of a satisfactory subdivision of the group formed by these genera, the new species described here is assigned to Nan-nocharax in keeping with its possession of the traditional diagnostic char-acter for the genus — a completely pored lateral line. Nannocharax maculicauda, new species Holotype.—MNn^ (Museum National d'Histoire Naturelle) 1981-608, 30.2 mm standard length (SL), collected September 2, 1964, by J. and G. Gery, in a still side arm of the upper Ivindo River opposite Bourassie, Gabon, at the juncture of the Djouah and Karouaga Rivers (approx. r20'N, 13°12'E) (see station 17, Gery, 1965:376-377). Paratypes. — 7 specimens (USNM [National Museum of Natural History] 224524, 3 specimens [1 cleared and stained], 23.5-28.7 mm SL; MNHN 1981-609, 1 specimen, 24.0 mm SL; Gery collection, 2 specimens, 23.1-23.3 mm SL; BM(NH) [British Museum (Natural History)] 1981-3.30:1, 1 spec-imen, 23.0 mm SL) taken with the holotype. Diagnosis. — Within Nannocharax, the relatively high lateral-line count
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