Morphological variation and phylogeography of frogs related to Pristimantis caryophyllaceus (Anura: Terrarana: Craugastoridae) in Panama

New World direct-developing frogs (Terrarana) are among the most diverse vertebrate groups in the world. Many Terrarana species are highly variable in colouration and morphology, often rendering it difficult to delineate spe - cies. Modern molecular and bioacoustic techniques are a relatively recent tool for understanding the various taxonomic entities. This affects also Pristimantis caryophyllaceus, a complex on which little research has previously been done. We ex - amined the variation of morphology, genetics, and colouration in specimens affiliated to P. caryophyllaceus from Panama, using different Molecular Operational Taxonomic Units (MOTUs) based on molecular phylogenetic lineages. Phylogeny, ecology, and distributional information for this species shed light on the position and species delineation of P. caryophylla­ ceus and its congeners in Panama. Our results demonstrate a high level of genetic diversity in P. caryophyllaceus -like popu - lations from Panama, which in fact comprise three main lineages that are geographically separated. Specimens from east - ern Panama tend to be larger, with more expanded finger disks and toe pads than specimens from western Panama. How - ever, aside from the significant morphological differences between MOTUs, the extent of variation within each MOTU is very large. Based on our extensive and integrative analysis, we suggest treating the three MOTUs of P. caryo phylla ceus populations as a single polymorphic species with very deep conspecific lineages as a result of the dynamic geological his - tory of the Isthmus of Panama. The validity of the recently described P. educatoris is not supported by our results and we therefore synonymize it with P. caryophyllaceus s.