Eleutherodactylus - Phylogenetics

Phylogenetics

The basis of forming this genus has been morphological, but sequence comparisons of protein-encoding DNA, mitochondrial DNA, and ribosomal RNA have shown that geographic range is a much more consistent predictor of cladistics for this group of frogs. The climbing habits of many species have evolved independently. All true members of the genus have been clustered into subgenera, but many less-related species require more genetic data before they are to be officially classified elsewhere. The theory that the Eleutherodactyline colonization of Central America and the Caribbean from their origins in South America occurred during the Cretaceous has fallen out of favor. The fossil record combined with molecular clock analyses indicate that the subgenera were probably founded by small groups of individuals by flotsam dispersal during the Eocene or Oligocene epochs. Land bridges would have been limited to facilitating dispersal between West Indian islands, however, the Oligocene division of Hispaniola and Cuba resulted in further speciation. The distribution of the subgenus Syrrhopus is most likely due to a secondary dispersal to Central America from the Greater Antilles during the Miocene. The formation of the Panama Isthmus during the Pliocene has caused some intercontinental distribution among the clades, although only twenty "South American frogs" have ever made it northwards after the original colonization. Sensu stricto, however, it should exclude clades with distributions south of the Panama Canal.