Simpsonichthys virgulatus

description

Description Morphometric data appear in Table 4. Largest specimen examined 52.7 mm SL. Dorsal profile convex from snout to end of dorsal-fin base, approximately straight on caudal peduncle. Ventral profile convex from lower jaw to end of anal-fin base, nearly straight on caudal peduncle. Body deep, compressed, greatest body depth at level of pelvic-fin base. Eye positioned on dorsal portion of head side. Snout blunt. Urogenital papilla cylindrical and short in males, pocket-shaped in females. Tip of dorsal and anal fins pointed in males; tip of dorsal fin slightly pointed and tip of anal fin rounded in female; dorsal and anal fins short in females. Short filamentous rays on tip of both dorsal and anal fins in males, tip of filaments reaching vertical through caudal-fin base. Anterior and posterior rays of dorsal-fin rays, including rays on tip of fin, unbranched; median rays branched. Caudal fin rounded. Pectoral fins elliptical. Posterior margin of each pectoral fin reaching vertical between base of 2 nd and 4 th anal-fins ray in males, between pelvic-fin base and anus in females. Tip of each pelvic fin reaching between base of 2 nd and 3 rd analfin rays in males, between urogenit

Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae).

diagnosis

Diagnosis Similar to S. auratus and S. trilineatus and distinguished from all other congeners in having the following combination of features: frontal squamation A-patterned (vs. E-patterned), anterior portion of flank golden with dark brown to black blotches in males (vs. never a similar color pattern), and dark gray spots over the entire flanks in females (vs. never a similar color pattern). Distinguished from S. auratus and S. trilineatus by having more black blotches on anterior portion of flanks in males (7 - 13, vs. 3 - 5), dark brown bars on whole caudal peduncle in males (vs. whole caudal peduncle purplish brown in S. auratus, and caudal peduncle light brown with three purplish brown stripes in S. trilineatus), and pectoral fins hyaline in males (vs. ventral portion of pectoral fins pale red).

Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae).

distribution

Distribution Ribeirao Entre Ribeiros floodplains, rio Paracatu drainage, rio Sao Francisco basin, Unai, Estado de Minas Gerais, Brazil (Fig. 1).

Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae).

materials_examined

Material examined Brazil: Estado de Minas Gerais, rio Paracatu drainage, rio Sao Francisco basin: UFRJ 6336, holotype, male, 41.5 mm SL; UFRJ 6337, 33 paratypes; UFRJ 6338, 6 paratypes (c & s); MCP 39931, 5 paratypes; Brazil: Estado de Minas Gerais: Municipio de Unai, temporary lagoon about 7 km from ribeirao Entre Rios, rio Paracatu drainage, rio Sao Francisco basin; G. C. Brasil, 26 May 2005.

Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae).