Morfologia da laringe em Cerdocyon thous (Linnaeus, 1766)

Abstract

Cerdocyon thous (crab-eating fox) is the most common wild canid in South American territory. The aim of this paper was to describe macroscopic, microscopic and comparative morphology of the larynx of this species. Analyses of larynges of sixteen specimens (four males and twelve females) revealed the topography, conformation, morphometrics, intrinsic muscles and histological characteristics. The larynx was positioned ventral to the axis and comprised one cricoid and one thyroid cartilage (hyaline), one epiglottis (elastic) and a pair of arytenoids (mixed). A pair of sesamoid cartilages was identified between the corniculate processes and the cricoid lamina. Morphometry revealed that thyroid cartilage was the largest. There were no conclusive signs of sexual dimorphism in the larynx of this species. Squamous stratified epithelium predominated and underwent transition to ciliated pseudo-stratified at the level of caudal thyroid and rostral cricoid portions. By comparison, larynx of C. thous showed similarity with the domestic dog, although the shape of cartilages has shown some variation.