Leptolebias, MYERS, 1952

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 : 149

LEPTOLEBIAS MYERS, 1952

Leptolebias Myers, 1952: 140 (type species: Cynopoecilus marmoratus Ladiges, 1934 , by original designation; first proposed as a subgenus of Cynolebias Steindachner, 1876 ).

Diagnosis: Distinguished from all other genera of the Cynopoecilina ( Notholebias , Cynopoecilus , and Campellolebias ) in having caudal fin elongate, longer than deep (vs. short, deeper than long), single anterior supraorbital neuromast ( Fig. 2 ) (vs. two or three), and distal third of dorsal fin in males without dark pigmentation (vs. extending pigmentation). Also distinguished from Notholebias by the absence of the second pharyngobranchial teeth, dermosphenotic and contact organs on male pectoral fin (vs. presence), opercular region with red reticulation in males (vs. red bars), and by having a wide, triangular basihyal ( Fig. 3 ) (vs. narrow, rectangular).

Distribution: Species of Leptolebias are found in the temporary pools of broad coastal plains, in two areas, separated by about 500 km: (1) between Maricá and Vila de Cava, Rio de Janeiro state, south-eastern Brazil ( Fig. 4 ), and (2) between Itanhaém, southern São Paulo state, and river basins draining into Paranaguá bay, Paraná state, southern Brazil ( Fig. 5 ).

Figures

Figure 2. Frontal squamation and neuromast pattern in Leptolebias aureoguttatus. Abbreviations: A–H, frontal scales A–H; AIS, anterior infraorbital series; AN, anterior nostril; ARN, anterior rostral neuromast; ASN, anterior supraorbital neuromast; PAS, parietal series; PBS, preorbital series; PN, posterior nostril; PRN, posterior rostral neuromast; PSS, posterior supraorbital series. Scale bar: 1 mm.

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 4. Geographical distribution of Leptolebias in São Paulo and Paraná states, southern Brazil: L. aureoguttatus (•) and L. itanhaensis (Ɨ).

Figure 5. Geographical distribution of Leptolebias in Rio de Janeiro state, south-eastern Brazil: 1, L. marmoratus, L. splendens, and L. opalescens; 2, L. marmoratus and L. opalescens; 3, L. splendens; 4, L. citrinipinnis.