title: Molecular phylogeny of the subfamily Stevardiinae Gill, 1858 (Characiformes: Characidae): classification and the evolution of reproductive traits.
abstract: BACKGROUND
  The subfamily Stevardiinae is a diverse and widely distributed clade of freshwater fishes from South and Central America, commonly known as "tetras" (Characidae). The group was named "clade A" when first proposed as a monophyletic unit of Characidae and later designated as a subfamily. Stevardiinae includes 48 genera and around 310 valid species with many species presenting inseminating reproductive strategy. No global hypothesis of relationships is available for this group and currently many genera are listed as incertae sedis or are suspected to be non-monophyletic.
  
  
  RESULTS
  We present a molecular phylogeny with the largest number of stevardiine species analyzed so far, including 355 samples representing 153 putative species distributed in 32 genera, to test the group's monophyly and internal relationships. The phylogeny was inferred using DNA sequence data from seven gene fragments (mtDNA: 12S, 16S and COI; nuclear: RAG1, RAG2, MYH6 and PTR). The results support the Stevardiinae as a monophyletic group and a detailed hypothesis of the internal relationships for this subfamily.
  
  
  CONCLUSIONS
  A revised classification based on the molecular phylogeny is proposed that includes seven tribes and also defines monophyletic genera, including a resurrected genus Eretmobrycon, and new definitions for Diapoma, Hemibrycon, Bryconamericus sensu stricto, and Knodus sensu stricto, placing some small genera as junior synonyms. Inseminating species are distributed in several clades suggesting that reproductive strategy is evolutionarily labile in this group of fishes.
authors.affiliation: Department of Ecology and Evolutionary Biology (EEB), University of Michigan, 1109 Geddes Ave., Ann Arbor, 48109, MI, USA. thomaz@umich.edu.|Departamento de Zoologia, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9500, Porto Alegre, 90501-970, RS, Brazil. thomaz@umich.edu.
authors.forename: Andréa T
authors.initials: AT
authors.lastname: Thomaz
authors.affiliation: Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC, 20052, USA. arciladk@gmail.com.|Department of Vertebrate Zoology, National Museum of Natural History Smithsonian Institution, PO Box 37012, MRC 159, Washington, DC, 20013, USA. arciladk@gmail.com.
authors.forename: Dahiana
authors.initials: D
authors.lastname: Arcila
authors.affiliation: Department of Biological Sciences, The George Washington University, 2023 G St. NW, Washington, DC, 20052, USA. gorti@gwu.edu.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Ortí
authors.affiliation: Departamento de Zoologia, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9500, Porto Alegre, 90501-970, RS, Brazil. malabarb@ufrgs.br.
authors.forename: Luiz R
authors.initials: LR
authors.lastname: Malabarba
mesh_terms: D000818:Animals; D002489:Central America; D060126:Characidae / Q000145:classification* / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D019143:Evolution, Molecular; D029941:Fish Proteins / Q000235:genetics; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial; D029941:Fish Proteins