Prenatal development of the sound transmitting apparatus in different embryonic stages of Malpolon monsspesulanus (squamata-serpentes)

Desenvolvimento pré-natal do aparelho transmissor de som em diferentes estágios embrionários de Malpolon monsspesulanus (Squamata-serpentes)

Abstract

The developmental investigation of sound transmitting apparatus is important in understanding the ontogenetic processes behind morphological diversity. The development of sound conducting apparatus was studied in Montpellier snake; Malpolon monspessulanus at 6.5, 7.2, 8.3 and 9.3 cm total body lengths using light microscopy study. The columella auris firstly appeared as undifferentiated rod shape mesenchymal cells. As the growth proceeded, it chondrified and differentiates into two main parts. In addition, the viscerocranium components which participate in formation of sound transmitting apparatus undergo critical organization. In more advanced stages, procartilagenous stylohyal chondrified and fuse with the well organized quadrate. These data considered as a base for functional and molecular mechanisms of sound transmitting apparatus studies and identification of diseases that may infect them.

Keywords:
columella auris; quadrate; stylohyal; tympanic cavity