Revisiting the contribution of larval characters to an analysis of phylogenetic relationships of basal anurans

The higher-level relationships of anurans have been explored by numerous studies, producing a variety of hypotheses. The relationships of the basal anurans ('archaeobatrachians') are, however, poorly known . In part, this may be because the adult morphology of basal anurans is derived and therefore may not provide suitable phylogenetic signal. Recently, several authors have shown the phylogenetic utility of information derived from anuran larvae. In this paper we conduct separate and combined analyses of anuran relationships based on adult and larval morphology. Our combined results suggest that anurans form two major clades ? the pipoids and all other frogs. Evidence also suggests that, taken together, Neobatrachia and Pelobatoidea form a monophyletic group. We discuss support for various groupings as shown by the different data sets. We also comment on the consequences of our phylogenetic hypothesis for the interpretation of reduction of vertebral elements and evolution of Orton's tadpole types in anurans.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 139 , 129?155.