Comparative ontogeny of the oral disc in leiuperid tadpoles (Anura, Leiuperidae)

VERA CANDIOTI, FLORENCIA; HAAD, BELÉN; BALDO, DIEGO; KOLENC, FRANCISCO; BORTEIRO, CLAUDIO; ALTIG RONALD

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2011 vol. 104 p. 330 - 345

0024-4066

Running title: Pathways of oral apparatus development in anuran tadpoles The oral apparatus of anuran tadpoles is a unique structure composed of soft and keratinized parts surrounding the mouth. Among the many variations, a common oral apparatus involves a dorsal gap in the marginal papillae, keratinized jaw sheaths, and two upper and three lower rows of labial teeth. In Leiuperidae, besides this generalized morphology, four configurations distinguish by the arrangement of the lower marginal papillae and the number of lower tooth rows. The study of the early oral ontogeny in twelve species representing these five configurations shows variations in the development of the lower marginal papillae and the third lower labial tooth row. Similar configurations may result from similar pathways (e.g., Physalaemus cuvieri group and Pseudopaludicola falcipes) or different pathways (e.g., generalized oral discs of Pleurodema and Physalaemus). Different oral configurations may result from overlapping trajectories ending at different stages (e.g., Physalaemus riograndensis and Ph. biligonigerus) or different trajectories (e.g., Ph. henselii and Ph. gracilis). Further studies are needed to interpret the role heterochrony has played in evolutionary change within this family. The unsuspected variation occurring in this transient structure highlights its evolutionary potential and might be insightful in studies of anuran phylogenies which are largely based on adult characters.