Identification of syntopic anuran species in early tadpole stages: correspondence between morphometric and genetic data

Abstract

Many European frogs and toads are relatively secretive species and except during breeding season, adults can rarely be seen during time-restricted fieldwork. In contrast, their tadpoles are easy to record and could be very useful in a brief biodiversity assessment. It is important to perform quick and accurate taxonomic identification of tadpoles, yet genetic methods are costly and cannot be routinely applied. We tested suitability of morphometric analysis for taxonomical distinction among tadpoles of early breeding local anuran species. Tadpole samples were collected simultaneously at three different locations in Republic of Serbia (South-eastern Europe) in habitats known to be breeding sites shared by brown frogs and the common toad. DNA barcoding verified Rana dalmatina, R. temporaria and Bufo bufo species, each collected in different location. The results of linear morphometric analyses suggested that relative head length and head width could be good discriminative characteristics for tadpoles of these two Rana species and those of B. bufo. To distinguish between tadpoles of two analyzed brown frog species, relative tail length could be used. For further development of the identification procedures for tadpoles of particular species,