Phylogenetic relationships of the South American Doradoidea (Ostariophysi: Siluriformes)

Abstract

A phylogenetic analysis based on 311 morphological characters is presented for most species of the Doradidae, all genera of the Auchenipteridae, and representatives of 16 other catfish families. The hypothesis that was derived from the six most parsimonious trees support the monophyly of the South American Doradoidea (Doradidae plus Auchenipteridae), as well as the monophyly of the clade Doradoidea plus the African Mochokidae. In addition, the clade with Sisoroidea plus Aspredinidae was considered sister to Doradoidea plus Mochokidae. Within the Auchenipteridae, the results support the monophyly of the Centromochlinae and Auchenipterinae. The latter is composed of Tocantinsia, and four monophyletic units, two small with Asterophysusand Liosomadoras, and Pseudotatiaand Pseudauchenipterus, respectively, and two large ones with the remaining genera. Within the Doradidae, parsimony analysis recovered Wertheimeriaas sister to Kalyptodoras, composing a clade sister to all remaining doradids, which include Franciscodorasand two monophyletic groups: Astrodoradinae (plus Acanthodorasand Agamyxis) and Doradinae (new arrangement). Wertheimerinae, new subfamily, is described for Kalyptodoras and Wertheimeria. Doradinae is corroborated as monophyletic and composed of four groups, one including Centrochirand Platydoras, the other with the large-size species of doradids (except Oxydoras), another with Orinocodoras, Rhinodoras, and Rhynchodoras, and another with Oxydorasplus all the fimbriate-barbel doradids. Based on the results, the species of Opsodoras are included in Hemidoras; and Tenellus, new genus, is described to include Nemadoras trimaculatus, N. leporhinusand Nemadoras ternetzi. Due to conflicting hypotheses of the phylogenetic position of Acanthodoras, Agamyxis, and Franciscodoras, these are considered as incertae sedisin Doradidae. All suprageneric taxa of the Doradoidea are diagnosed based on synapomorphic morphological characteristics.