Notholebias, Costa, 2008

Costa, Wilson J. E. M., 2008, Monophyly and taxonomy of the Neotropical seasonal killifish genus Leptolebias (Teleostei: Aplocheiloidei: Rivulidae), with the description of a new genus, Zoological Journal of the Linnean Society 153 (1), pp. 147-160 : 156-157

NOTHOLEBIAS GEN. NOV.

Type species: Cynolebias minimus Myers, 1942 .

Diagnosis: Distinguished from all other genera of Cynopoecilina ( Leptolebias , Cynopoecilus , and Campellolebias ) by the possession of dermosphenotic (vs. dermosphenotic absent), basihyal narrow, roughly rectangular ( Fig. 3 ) (vs. wide, triangular), welldeveloped contact organs on most inner surface of pectoral fin in males (vs. contact organs reduced or absent), opercular region with red bars in males ( Fig. 11 ) (vs. red reticulation), and iridescent bars or vertical lines on caudal fin in males ( Fig. 11 ) (vs. bars absent). Also differs from Leptolebias in having teeth on second pharyngobranchial (teeth absent), caudal fin subtruncate to rounded, short, deeper than long ( Fig. 11 ) (vs. elliptical to lanceolate, longer than deep), two anterior supraorbital neuromasts (vs. single anterior supraorbital neuromast), and dark pigmentation extending over entire dorsal fin in males (vs. not extending to distal third of dorsal fin).

Included species: Notholebias minimus (Myers) comb. nov.; Notholebias fractifasciatus (Costa) comb. nov.; and Notholebias cruzi (Costa) comb. nov.

Distribution: Coastal plains of south-eastern Brazil, between the São João river floodplains and Itaguaí, Rio de Janeiro state.

Etymology: The name Notholebias is an allusion to the superficial resemblance between species included in the new genus and some species of the African killifish genus Nothobranchius Peters, 1868 , in particular Nothobranchius lourensi Wildekamp, 1977 , which have similar colour patterns and similar body proportions (from the Greek nothos = false, taken from the name Nothobranchius , and lebias = small fish, a name often used to compose generic names of rivulid fishes). Gender masculine.

Figures

Figure 3. Osteological features in Leptolebias and Notholebias: A, medial portion of hyoid and branchial skeleton, dorsal view, of Leptolebias citrinipinnis. B, medial portion of hyoid and branchial skeleton, dorsal view, of Notholebias fractifasciatus. C, anguloarticular region, left side, lateral view, of L. citrinipinnis. D, jaw suspensorium, left side, lateral view, of N. fractifasciatus. Abbreviations: AA, anguloarticular; B1–B3, basibranchials 1–3; BB, basibranchial cartilage; BC, basihyal cartilage; BH, basihyal; H1–H3, hypobranchials 1–3; HY, hyomandibula; MS, mesopterygoid; MT, metapterygoid; PL, autopalatine; PO, preopercle; QU, quadrate; RA, retroarticular; SY, sympletic. Larger stippling indicates cartilage. Scale bar: 1 mm.

Figure 11. Notholebias minimus, male, not preserved, about 20-mm standard length (1 day after collection); Brazil, Estado do Rio de Janeiro, Seropédica (photo by W. J. E. M. Costa).