Table of Contents
International Journal of Evolutionary Biology
Volume 2011 (2011), Article ID 360654, 16 pages
Research Article

A Molecular Perspective on Systematics, Taxonomy and Classification Amazonian Discus Fishes of the Genus Symphysodon

1Laboratório de Evolução e Genética Animal, Departamento de Biologia, Universidade Federal do Amazonas, Avenida Rodrigo Octávio Jordão Ramos, 3000, 69077-000 Manaus, AM, Brazil
2Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, Unidade Vitória, Avenida Vitória, 1729, 29040-780 Vitoria, ES, Brazil
3Biology Department, University of Puerto Rico—Rio Piedras, 00931 San Juan, PR, Puerto Rico

Received 21 December 2010; Accepted 2 May 2011

Academic Editor: Martin J. Genner

Copyright © 2011 Manuella Villar Amado et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


With the goal of contributing to the taxonomy and systematics of the Neotropical cichlid fishes of the genus Symphysodon, we analyzed 336 individuals from 24 localities throughout the entire distributional range of the genus. We analyzed variation at 13 nuclear microsatellite markers, and subjected the data to Bayesian analysis of genetic structure. The results indicate that Symphysodon is composed of four genetic groups: group PURPLE—phenotype Heckel and abacaxi; group GREEN—phenotype green; group RED—phenotype blue and brown; and group PINK—populations of Xingú and Cametá. Although the phenotypes blue and brown are predominantly biological group RED, they also have substantial contributions from other biological groups, and the patterns of admixture of the two phenotypes are different. The two phenotypes are further characterized by distinct and divergent mtDNA haplotype groups, and show differences in mean habitat use measured as pH and conductivity. Differences in mean habitat use is also observed between most other biological groups. We therefore conclude that Symphysodon comprises five evolutionary significant units: Symphysodon discus (Heckel and abacaxi phenotypes), S. aequifasciatus (brown phenotype), S. tarzoo (green phenotype), Symphysodon sp. 1 (blue phenotype) and Symphysodon sp. 2 (Xingú group).