Condrocrânio e cavidade oral de girinos da família Odontophynidae (Anura): descrição e considerações filogenéticas

• Autor(a) principal: Nascimento, Filipe Augusto Cavalcanti do
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal de Alagoas (UFAL)
• Texto Completo: http://www.repositorio.ufal.br/handle/riufal/5389
• topic: Morfologia larval; Girino – Anatomia cranial e oral; Macrogenioglottus; Odontophrynus; Proceratophys; Filogenia; Larval morphology; Tadpole - Cranial anatomy; Tadpole - Oral anatomy; Phylogeny; CNPQ::CIENCIAS BIOLOGICAS

The family Odontophrynidae was suggested recently to include the genera Macrogenioglottus (1sp.) Odontophrynus (11 spp.) and Proceratophrys (29 spp.). The similarity of these three taxa was already established for decades, nevertheless, the knowledge about the interspecific relationship within this clade is still in the initial stage. Amphibians are vertebrates that have as one of its main features the presence of a larval stage in its development. The utilization of characters from that stage as a tool to understand the evolutionary relationships of anurans has grown in recent years. Characters of internal morphology, mainly those from chondrocranium and oral cavity, have shown useful in understanding the phylogenetic relationships of frogs. Thus, the main goals of this study were to describe the chodrocrania and oral cavities of four species of Odontophrynus, six of Proceratophrys and Macrogenioglottus alipioi and to use these characters to reconstruct a phylogenetic hypothesis to test both the monophyly of the family and its genera. To study the chondrocrania, 60 tadpoles were cleared and double-stained and for the study of the oral cavity, 12 tadpoles were dissected for analysis in a scanning electron microscope. For the cladistic analysis, 47 characters were used whereas 39 were informative. Maximum Parsimony analysis was conducted using heuristic searches. The chondrocranium and the oral cavity of four species of Odontophrynus were very similar. Some characters such as the processus pseudopyterigoideus length, shape of the divergence of hypobranchial plates, number of postnarial papillae, and number of projections lateral ridge papillae supported in part the existence of two of the three current morphogroups (O. americanus and O. cultripes species group), while other characters varied in populations or even individual levels. The variability found among the six studied Proceratophrys species was informative systematically, although some of the phenetic groups proposed to its genus were not supported (e.g., P. cristiceps species group). Some characters have shown useful in the diagnosis of some species and others, such as the interruption of the medial portion of the dorsal glandular zone, were identified as probable synapomorphies of the genus. Macrogenioglottus alipioi, in turn, showed some exclusive features such as an average total length greater, cartilage suprarostral with two separate bodies, the processus hyoquadrati formed by two projections and a fourth spicule separated from hypobranchial plates. Twenty-one equally parsimonious trees recovered both the monophyly of the family as well as the genus Proceratophrys with two and three synapomorphies respectively. However, there was no resolution between Odontophrynus and Macrogenioglottus. It is necessary to increase the number of terminal taxa, as well as the number of characters to reconstruct a better resolved phylogenetic hypothesis. However, the hypothesis generated corroborated the phylogenetic hypotheses proposed mainly from molecular characters, demonstrating the usefulness of the internal larval characters for phylogenetic reconstructions.