Sequência de ossificação craniana de Aparasphenodon brunoi Miranda-Ribeiro, 1920, com comentários sobre o condrocrânio e o desenvolvimento da ornamentação óssea (Amphibia, Anura, Hylidae)

Abstract

The development of cranial bones of Aparasphenodon brunoi Miranda -Ribeiro, 1920 was studied by the examination of tadpoles, froglets and juveniles, cleared and alcian blue - alizarin stained. The animals were staged using Gosner (1960) for tadpoles, and the extension and degree of cranial ornamentation for froglets and juveniles. The tadpole, the chondrocranium at different developmental stages, the sequence of cranial ossification, the cartilages and bones of the adult cranium, and the development of crests and spines that ornaments the cranial roof elements were described. Among the main resulta were the develoi;:ment of the prenaaal bone from two independent oaaification centers, the abaence of a dermal aphenetmoid, and the ornamentation developnent from the bones surfacea and not from the ossification of the dermal layer - the proceas of coosaification waa not obaerved. The morphology of the chondrocranium and the oaaification aequence were compared with thoae from the literature on other apeciea. Further diacusaion waa presented for: a model developed for studying the timing of cranial osaification among anurana; the use of stages in the development tables as a reference for description and morpholoical compariaon; the use of ontogenetical data; the homology of certain bone elemente; the proceas of co-oaaification; and the relationahip among A. brunoi and the caaque-headed group, baaed on the cranial morphology.