The South American annual killifish genus Austrolebias (Teleostei: Cyprinodontiformes: Rivulidae): phylogenetic relationships, descriptive morphology and taxonomic revision. Wilson J. E. M. Costa Zootaxa 2006 1213 1 162 JWVQ 135274 Rivulidae Austrolebias CoL Animalia Cyprinodontiformes 97 Chordata species bellottii Rivulidae Austrolebias CoL Animalia Cyprinodontiformes 97 Chordata species melanoorus  Diagnosis Distinguished from remaining taxa of the genus Austrolebiasin having anteromedian rays of anal fin long in females, resulting in a nearly triangular fin shape (vs. rays short and fin rounded), four to six contact organs on each flank scale in males (vs. a single contact organ per scale) (reversed in A. melanoorus), and anterior arm of ceratobranchial 5 longer than posterior arm (vs. shorter) (homoplastically occurring in A. cinereus, but not present in all species of clade A5, considered a reversal).