| Abstract | Aim We study the Neotropical poison frogs of the genus Dendrobates Wagler,1830 in order to clarify their phylogenetic relationships and biogeographicalhistory. The genus Dendrobates is an excellent taxon for examining patterns ofNeotropical diversification as the four major species groups appear to correspondroughly to distinct geographical regions: (1) trans-Andean, (2) Andean foreland,(3) Brazilian Shield and (4) Guianan Shield/Central America. In order to test theagreement of five of the most prominent hypotheses of Amazoniandiversification, phylogenetic patterns were examined for agreement withpatterns predicted by these hypotheses.Location Central and South AmericaMethods The phylogenetic relationships of the genus Dendrobates wereexamined from novel and existing (GenBank) sequences of four mitochondrialloci totalling c. 1400 bp from 40 specimens of 22 different species usingmaximum parsimony and Bayesian methods. Results were compared withtraditional taxonomic arrangements by means of SH tests. Phylogeneticrelationships and genetic distances were used to test the adequacy of variousdiversification hypotheses.Results Phylogenetic analyses support the restructuring of two species groupsof Dendrobates and the creation of a new species group. Statistical tests ofthe traditional taxonomic arrangement indicate a significantly bad fit tothe molecular data. This restructuring has important implications for theunderstanding of the historical biogeography of Dendrobates. Biogeographicalpatterns within this genus suggest that a complex interaction of biotic and abioticfactors since the Eocene have produced the diversity observed today.Main conclusions The current classification of Dendrobates into discrete speciesgroups does not accurately reflect evolutionary history. Data presented herestrongly support a monophyletic Brazilian Shield lineage whose members havepreviously been split among the quinquevittatus and tinctorius groups.Furthermore, previous attempts at elucidating the historical biogeography ofthis genus were compromised by incomplete sampling and conclusions drawnfrom a paraphyletic ingroup. Our findings demonstrate a role for numeroushypotheses of diversification (e.g. river, refuge, disturbance–vicariance) in thehistory of Dendrobates, supporting previous warnings about the dangers of oversimplificationin the study of Neotropical diversification
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