Morphological evolution of Ceratophryinae (Anura, Neobatrachia)

Abstract

Body form is one of the major consequences of development, and diversification of body shapes implies developmental changes among species. In anurans, changes in the timing of developmental events or heterochrony, have been emphasized as a source of variation in the patterns of development that has lead to diverse morphology. Herein, different approaches are used to explore morphological traits in members of the Ceratophryinae (Anura: Leptodactylidae), a group of frogs with some features produced by overdevelopment. Cladistic analyses were conducted in order to distinguish the shared history of Ceratophrys, Chacophrys and Lepidobatrachus and other anurans. From these studies, morphological variation of selected skeletal features in ceratophryines reveals the presence of ancient structures, which have been considered lost in the neobatrachian phylogeny, integrated in particular designs. Thin-plate spline morphometric analyses of skull shapes among ceratophryines describe Lepidobatrachus as the most distinctive shape. Moreover, thin-plate spline morphometric analyses among anurans show divergent skull shapes between ceratophryines and other anurans, reflecting that the skull shapes of ceratophryines are a result of peramorphosis (increase of developmental rates). This study represents the first detailed examination of the role of peramorphosis in a clade of anurans. © 2006 Blackwell Verlag.