South American Cyprinodont Fishes Allied to Cynolebias with the Description of a New Species of Austrofundulus from Venezuela

Abstract

Austrofundulus dolichopterus is described as a new species of annual cyprinodont and was recently discovered in temporary ponds in the states of Guarico, Cojedes, and Apure, Venezuela. It is placed in Austrofundulus on the basis of caudal fin shape and color pattern. It differs from other species of this genus by lacking caudal fin scales, in having elongate streamers on the caudal fin, elongate dorsal and anal fins, and a dorsal fin slightly in advance of the anal fin. In an attempt to determine its closest relatives, characters defining the South American cyprinodont genus Cynolebias and its allies were reevaluated. It was found that Cynolebias, Pterolebias, Cynopoecilus, Rachovia, Austrofundulus, Leptolebias, and Simpsonichthys cannot be separated on the basis of characters currently in use such as the relative positions of the dorsal and anal fins, caudal peduncle and fin shape, distribution of scales on the caudal fin, sexual dimorphism in the number of dorsal and anal fin rays, and variations in the presence or the juxtaposition of the two pelvic fins. Despite these findings, we do not believe it wise to synonymize any of these genera until reevaluation of all neotropical cyprinodont genera can be accomplished. When sufficient material becomes available for a more complete study, some of the genera here tentatively recognized may prove to be valid on the basis of other characters. For example, northern South American annual fishes tend to have pointed upper and lower caudal fin lobes and have scales distributed over the caudal fin. Southern species have a rounded or simple pointed caudal fin and lack scales on the caudal fin. Further study may show these differences to be of generic significance.