Phylogenetic relationships in Xenurobrycon Myers & Miranda-Ribeiro and discussion on miniaturization in the genus (Stervardiinae: Characidae: Characiformes)

• Grant number: 18/23354-6
• Support type: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2019
• Effective date (End): October 31, 2019
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal Investigator: Manoela Maria Marinho Koh
• Grantee: Péricles Vinícius Gentile
• Home Institution: Museu de Zoologia (MZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/09321-5 - Miniature Characiformes (Teleostei: Ostariophysi): evolution, diversity and biogeography, AP.BTA.JP

Abstract

Xenurobrycon, a genus of Xenurobryconini, Stervardiinae, includes six miniature species that occur in the basin of Amazon river and Paraguay. Although the intergeneric relations of Xenurobryconini were evaluated in previous phylogenetic studies, there is not any well-known study focused to understand the relations between the species of Xenurobrycon. Moreover, these individuals give a series of characteristics probably related to the small size. This present proposal aims to elucidate the kinship relations of these specimens by means of phylogenetic analysis and assess the anatomical reductive structures of Xenurobrycon in a comparative analysis with the ontogenetic sequence of a basal Characidae, Salminus brasiliensis, in order to understand if these characteristics are results of the miniaturization's evolution in the tribe.