Teeth and their sex-dependent dimorphic shape in three species of Costa Rican plethodontid salamanders (Amphibia : Urodela)

Citation
J. Ehmcke et G. Clemen, Teeth and their sex-dependent dimorphic shape in three species of Costa Rican plethodontid salamanders (Amphibia : Urodela), ANN ANATOMY, 182(5), 2000, pp. 403-414
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Experimental Biology
Journal title
ANNALS OF ANATOMY-ANATOMISCHER ANZEIGER
ISSN journal
0940-9602 → ACNP
Volume
182
Issue
5
Year of publication
2000
Pages
403 - 414
Database
ISI
SICI code
0940-9602(200009)182:5<403:TATSDS>2.0.ZU;2-N
Abstract
The shape of the teeth and their sex-dependent dimorphic expression in thre e species of Costa Rican plethodontids (Bolitoglossa subpalmata, Oedipina u niformis and Nototriton abscondens) were studied using light microscopy and scanning electron microscopy. The teeth of the vomerine tooth patches are about one third larger than the teeth of the jaws in B. subpalmata and O. uniformis, whereas all teeth of N. abscondens are of about uniform size. The occurrence of bicuspid tooth g erms in the fetus proves that primary teeth are bicuspid in these directly developing plethodontids. Females possess only bicuspid teeth consisting of a pedicel and a crown, as is considered characteristic for urodeles after metamorphosis. Adult males possess conical monocuspid teeth on the premaxil lary. These teeth - which are similar to the typical late larval tooth of s alamanders presenting a larval stage - are about twice as big as the neighb ouring bicuspid maxillary teeth. N. abscondens males possess some monocuspi d teeth and teeth of aberrant shapes on the premaxillary and the maxillarie s. A tendency to build more monocuspid teeth in the premaxillary region tha n in the maxillary region can be observed in this species. We suppose that different degrees of sensitivity to androgens in each secti on of the dental lamina of the upper jaw cause the secondary occurrence of conical monocuspid teeth predominantly on the premaxillary section.