Rivulus kirovskyi, a new killifish from the central Amazon, Brazil (Cyprinodontiformes: Rivulidae)

Wilson J E M Costa

doi:10.1590/s1679-62252004000100002

Abstract

Rivulus kirovskyi, new species, from the central Amazon, lower rio Negro drainage, northern Brazil, is described. It is a member of an assemblage that includes R. amanapira, R. atratus, R. ornatus, R. rectocaudatus, R. romeri, R. tecminae, and R. uakti, and is diagnosed by a unique pattern of frontal squamation and a derived color pattern of the infraorbital region. Relationships of the new species with other taxa of the group are unclear at the present. It is similar to R. atratus, R. ornatus, and R. romeri in having an apomorphic reduction of anal-fin rays and by the absence of caudal spot in females, and similar to R. amanapira, R. rectocaudatus, R. romeri, R. tecminae, and R. uakti, by the absence of preopercular canal and dermosphenotic. Rivulus kirovskyi differs from all other species of the group by its unique color pattern of the caudal fin in males.

Highlights

Rivulus kirovskyi, espécie nova, da Amazônia central, drenagem do baixo rio Negro, é descrita
New species, from the central Amazon, lower rio Negro drainage, northern Brazil, is described. It is a member of an assemblage that includes R. amanapira, R. atratus, R. ornatus, R. rectocaudatus, R. romeri, R. tecminae, and R. uakti, and is diagnosed by a unique pattern of frontal squamation and a derived color pattern of the infraorbital region
Relationships of the new species with other taxa of the group are unclear at the present

Summary

Material and Methods

The abbreviation c&s means specimens cleared and stained caudal peduncle Similar to R. amanapira, R. atratus, R. ornatus, R. rectocaudatus, R. romeri, R. tecminae, and R. uakti Costa, and distinguished from all other species of the genus by. R. atratus, R. ornatus and R. romeri and distinguished from the remaining congeners by having fewer anal-fin rays (8-10, vs 11-19). O atratus by having a marginal dark reddish brown stripe on the caudal fin in males (vs dark marginal stripes absent). P by having short anal fin, its tip reaching vertical through rounded, posterior margin on vertical anterior to pelvic-fin base. Tip of pelvic fin reaching between base of 1st and 3rd anal-fin ray in male, and urogenital opening in female. Named in honor of the biologist Alexandre Kirovsky, collector of most specimens of the type series

Discussion

Findings

Literature Cited