Molecular Phylogeny of the Neotropical Knifefishes of the Order Gymnotiformes (Actinopterygii)

The order Gymnotiformes, the Neotropical electric knifefishes, is comprised of 200+ species divided into the families Apteronotidae, Gymnotidae, Hypopomidae, Rhamphichthyidae, and Sternopygidae. These species inhabit a variety of freshwater habitats throughout Central and South America. To date, attempts at resolving the internal relationships of Gymnotiformes have yet to produce an unambiguous species-level phylogeny. In order to resolve the phylogeny, I collected molecular data from seven nuclear and two mitochondrial genes for 197 species and performed parsimony and Bayesian phylogenetic analyses. All families were recovered as monophyletic with the exception of Gymnotidae; the electric eel Electrophorus, previously considered a member of this family, was instead found to be sister to all other Gymnotiformes. The topologies resulting from this study provide a highly-resolved species phylogeny which will form the basis for future studies of species diversification and ecological and evolutionary patterns.M.Sc.2017-12-06 00:00:0