Volume 21, Issue 4 – 15 October 2015
Dalton Tavares Bressane Nielsen and Didier Pillet: Austrolebias accorsii, a new annual fish (Cyprinodontiformes: Rivulidae: Cynolebiatinae) from the upper río Grande basin, Amazon basin, Bolivia, pp. 172-179
Austrolebias accorsii new species is described from Bolivia, departamento de Santa Cruz, Rio Grande, upper Mamoré basin. This is the first record of the genus Austrolebias at the Amazon basin. Austrolebias accorsii new species is distinguished from other members of the Austrolebias bellottii species group by the following combination of characters: absence of dots or spots on body and fins (vs. presence), absence of bars on body (vs. presence), anal-fin origin between neural spines (13th-14th vs. 5th-11th) in males. Austrolebias accorsii females differ from females of other species of the Austrolebias bellottii species group by the combination of a higher number of anal-fin rays (31-32 vs. 23-30), colour pattern of the sides of body light yellowish brown, without bars; usually 1-3 black spots on anterocentral portion of flanks, surrounded by metallic green spots, black spots of random size and quantity on the posterior portion of the body to the caudal peduncle (vs. with bars, one to sixteen black spots on anterocentral portion of flanks without metallic green spots, absent black spots in peduncle caudal).