Cranial Morphology and the Evolution of West Indian Toads (Salientia: Bufonidae): Resurrection of the Genus Peltophryne Fitzinger

Abstract

resulted from dermal co-ossification of the skull, notably the formation of rostral elements at the front of the maxillary arch, and the direct articulation of the zygomatic ramus of the squamosal with the maxillary bone. The degree and effect of dermal co-ossification varies substantially from one species to another, apparently differences in adult phenotypes resulting from developmental perturbations during the ontogeny of each species. The diagnostic characteristics of the group warrent its recognition at the generic level, and Fitzinger's Peltophryne (type species: Bufo peltocephalus Tschudi by original designation) is available. Peltophryne appears to be an ancient Antillean lineage whose history in the West Indies presents a spectacular example of adaptive radiation from a single ancestral invasion. F OR years the genus Bufo has frustrated herpetologists as species groups are reorganized with disturbing frequency, but with little phylogenetic resolution. Currently, the West Indian toad fauna (Bufo), exclusive of the introduced B. marinus, includes nine species distributed among three islands in the Greater Antilles. I believe these bufonids comprise their own genus, Peltophryne, as will be demonstrated in the discussion. Six of these species occur on Cuba: P. cataulaciceps, P. empusa, P. gundlachi, P. longinasa, P. peltocephala and P. taladai. Two species are described from Hispaniola, P. fluviatica and P. guntheri, and one species, P. lemur, is known from Puerto Rico (Fig. 1), The distribution and intraspecific variation of some of these toads were treated by Schwartz in a series of papers (1959a, 1960, 1972), but their phylogenetic position within the family has received only conjectural treatment. Ruibal (1959) suggested that P. peltocephala, P. gundlachi and P. cataulaciceps formed a group to which Schwartz (1972) subsequently intimated that the remaining Antillean species were related with the exception of P. longinasa. Tihen (1962) placed the West Indian species in the Caribbean section of his Bufo valiceps group that united several North and South American