Systematic revision of the genus Lachesis daudin, 1803 (Serpentes, viperidae)

The genus Lachesis Daudin, 1803 was partitioned into six geographic groups to evaluate the taxonomic status and phylogenetic relationships among these groups. Characters of external morphology and hemipenial anatomy were evaluated. Results obtained through the phylogenetic and statistical analyses support recognition of the Central American species L. melanocephata and L. stenophrys as distinct species, whereas the South American L. muta is recognized as monotypic, without further differentiation in subspecies. These results provide further evidence of the independence of the Central American and South American lineages and are congruent with other studies based on molecular data.