Morfologia comparada da laringe dos Pelecaniformes (Aves)

Abstract

A preliminary description of the external morphology and of the skeleton of the larynx in sevens species, which are representative of all Pelecaniformes families, set anatomical patterns which allow for the caracterization of each one of the groups described herein. lt also allowed for the establishment of two larger welldefined groupings: the first, comprising the Phaethontidae and the Fregatidae, is characterized by the existence of a Sulcus laringealis, a convex rostral bordered Cartilago cricoidea, and calcified edges only in the Alae cricoidea. The second large group, comprising the Pelecanidae, the Sulidae, the Phalacrocoracidae and the Anhingidae, is characterized by the absence of a Sulcus laringealis as well as by an elongated Cartilago cricoidea rostral border, and the progressiva calcification of the Alae cricoidea. Results corroborate the prevailing opinion among authors that Fregatidae and Phaethontidae would form two separate strains within the universe of the Pelecaniformes and the present analysis still showed very clearly the remarkable peculiarities observed in the Phaethontidae, among which highlight the absence of a defined preglottic region, the presence of Pappilae laringealis along the entire dorsal surface of Mons laringealis and the absence of fusion between Cartilago traquealis and Cartilago cricoidea.