Simpsonichthys constanciae

Simpsonichthys constanciae

Key to species of the S. constanciae group 1 No black spots on male flank; dorsal and anal fins of male with short filamentous rays, tip never reaching vertical through posterior margin of caudal fin; male with contact organs on flank scales and inner surface of upper pectoral­fin rays ............................ 2 ­ Four longitudinal rows of round black spots on male flank; dorsal and anal fins of male with long filamentous rays, tip posteriorly surpassing posterior margin of caudal fin; contact organs of flank and pectoral fin absent ................................ S. constanciae 2 Anal fin pointed in male; bars restricted to anterior portion of male flank; no bars on male anal fin................................................................................................................. 3 ­ Anal fin rounded in male; reddish brown bars alternated with bright greenish blue bars on whole male flank; oblique brown bars on male anal fin ............................ S. suzarti 3 No bright dots on caudal and anal fins of male............................................................. 4 ­ White dots on dorsal fin and concentrated on dorsal half of male caudal fin.......

Simpsonichthys suzarti sp. n. (Teleostei: Cyprinodontiformes: Rivulidae): a new annual fish from the Rio Pardo floodplains, northeastern Brazil

biology_ecology

Habitat Temporary pools in a semi-arid coastal areas, usually in places widely exposed to the sun.

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

description

Description Morphometric data appear in Table 1. Largest specimen examined 41.5 mm SL. Dorsal profile slightly concave on head, convex from nape 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 lateral portion of head side. Snout blunt. Urogenital papilla cylindrical and short in males, pocket-shaped in females. Tip of dorsal and anal fins pointed and long in males, rounded in females. Tip of dorsal and anal fins with long filamentous rays in males, tip of filaments reaching vertical behind posterior margin of caudal fin. Dorsal and anal-fin rays unbranched. Caudal fin rounded. Pectoral fins elliptical. Posterior margin of pectoral fins reaching vertical through base of 6 th anal-fin ray in males and reaching urogenital papilla in females. Tip of pelvic fin reaching base of 4 th anal-fin ray in males and base of 2 nd anal-fin ray in females. Pelvic-fin bases medially in contact. Dorsal-fin origin on vertical through base of 6 th or 7 th anal-fin ray, between neural spines of

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

diagnosis

Diagnosis Distinguished from all other species of the subgenus in having all anal-fin rays unbranched (vs. some median rays branched), four longitudinal rows of rounded black spots on sides of body in males (vs. never a similar color pattern), long filamentous rays on tip of dorsal and anal fins in males, tip of longest dorsal and anal rays extending beyond posterior border of caudal fin (vs. filamentous rays short, never reaching posterior margin of caudal fin), dorsal-fin origin between neural spines of vertebrae 10 and 11 in males (vs. between neural spines of vertebrae 11 and 13), and absence of contact organs on flank and pectoral fin (vs. contact organs present in males).

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