Phylogeny of the Neotropical genus Gephyrocharax (Characiformes: Characidae: Stevardiinae), with remarks on the tribe Stevardiini

VANEGAS RÍOS, JAMES ANYELO

ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018 vol. 182 p. 808 - 829

0024-4082

Stevardiinae, which consists of 326 species and 44 genera, is a monophyletic subfamily within the family Characidae. In a recent classification of the subfamily, the tribe Stevardiini was expanded from three (Corynopoma, Gephyrocharax and Pterobrycon) to six genera by the addition of Chrysobrycon, Hysteronotus and Pseudocorynopoma. However, no morphological evidence has supported this definition of the tribe and the monophyly of Gephyrocharax. To address these issues, a phylogenetic study of most stevardiins focusing on Gephyrocharax was conducted. A data matrix including 532 characters and 213 taxa (73 stevardiines, 19 of which were stevardiins) was processed using maximum parsimony in TNT 1.5. All characters were analyzed under extended implied weighting, exploring 21 k values. A strict consensus (comprising the most stables trees obtained) was used as the final topology. The results supportthe current definition of Stevardiini, as well as the monophyly of Chrysobrycon, Gephyrocharax and Pterobrycon. Corynopoma was obtained as the sister group of Gephyrocharax, the latter being phylogenetically diagnosed by twosynapomorphies associated with caudal-fin morphology of adult males. The following interspecific relationships within Gephyrocharax are hypothesized: (G. martae ((G. chocoensis (G. major (G. atracaudatus, G. intermedius)))(G. venezuelae (G. sinuensis (G. valencia (G. caucanus (G. melanocheir, G. torresi)))))))).