A new species of direct-developing frog of the genus Eleutherodactylus (Anura: Eleutherodactylidae) from Tamaulipas, Mexico.

The number of species of the subgenus Syrrhophus, genus Eleutherodactylus has increased rapidly in the last eight years, due to recent taxonomic studies. This subgenus of direct-developing frogs is well represented in Mexico, which harbors more than 90% of the species richness reported for the subgenus. In this study, we describe one new species, Eleutherodactylus (Syrrhophus) coelum sp. nov. from the El Cielo Biosphere Reserve in Tamaulipas, Mexico, based on morphological and molecular data. The new species, which was previously assigned to E. cystignathoides, differs from its congeners mainly by its small size and by having the tips of Finger III and IV expanded to twice the width of the narrowest part of these fingers. Phylogenetic analyses recovered a well-supported relationship of the new species as the sister group to an undescribed taxon from San Luis Potosí. This analysis also indicates there are more lineages wating for description.