Morphological evolution in Ceratophryinae frogs (Anura, Neobatrachia): The effects of heterochronic changes during larval development and metamorphosis

FABREZI, MARISSA; QUINZIO, SILVIA INÉS

ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2008 vol. 154 p. 752 - 780

0024-4082

Heterochrony produces morphological change with effects in shape, size and/or timing of developmental events of a trait related to an ancestral ontogeny. This paper analyzes heterochrony during the ontogeny of Ceratophryinae (Ceratophrys, Chacophrys, and Lepidobatrachus), a monophyletic group of South American frogs with larval development, and uses different approaches to explore their morphological evolution: (1) Inferences of ancestral ontogenies and heterochronic variation from a cladistic analysis based on 102 morphological larval and adult characters recorded in 10 anuran taxa; (2) Comparisons of size, morphological variation, and timing (age) of developmental events based on study of ontogenetic series of ceratophryines, Telmatobius atacamensis, and Pseudis platensis. We found Chacophrys as the basal taxon. Ceratophrys and Lepidobatrachus share most derived larval features resulting from heterochrony. Ceratophryines share high rates of larval development but differ in rates of postmetamorphic growth. The ontogeny of Lepidobatrachus exhibits peramorphic traits produced by early onset of metamorphic transformations that are integrated in an unusual larval morphology. This study represents an integrative examination of shape, size and age variation and discusses evolutionary patterns of metamorphosis.