Phylogenetic analysis in Deuterodon and similar genera, as a model of search for evolutionary patterns in monophyletic groups of Characidae (Ostariophysi, Characiformes)

• Grant number: 24/23112-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: August 01, 2025
• End date: July 31, 2028
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: Claudio de Oliveira
• Grantee: Gabriel de Carvalho Deprá
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated research grant: 20/13433-6 - Phylogeny and molecular identification of fishes of the superorder Ostariophysi (Chordata: Actinopterygii) using genomic approaches, AP.TEM

Abstract

Until recently, Deuterodon was considered a monophyletic genus occurring only in some of the coastal drainages in southern and southeastern Brazil, including seven species. Two recent phylogenetic studies, with morphologic and genomic data, brought changes to the classification of the genus, which now includes 22 species, from Bahia to Uruguay. Most of these previously belonged to Astyanax, although others previously were included in Probolodus or Hyphessobrycon. These studies also indicated clearly the close relationship between Deuterodon and Myxiops. One of them also proposed a series of morphological synapomorphies and diagnostic characters for Deuterodon, although it is not clear yet which other species of Acestrorhamphidae may belong in the genus. Moreover, the very identity of some of the species previously included in Deuterodon is doubtful, therefore they are in need of taxonomic review. The objective of this project is to clarify the taxonomy of those species, to propose a new phylogenetic hypothesis for Deuterodon, based on morphologic and genomic (UCEs) data, to find a diagnosis for the genus based on external morphology, and to verify if the presence of trophic specialisations correlates with high mutation rates. (AU)