Descriptions of anatomical differences between skulls and mandibles of Equus zebra and E. burchelli from Southern Africa

Abstract

The external anatomical differences between the skulls and mandibles of 10 mountain zebras Equus zebra and 10 plains zebras E. burchelli of both sexes were studied. The nomenclature used conforms to Nomina Anatomica Veterinaria (1983). Eleven structural differences are described for the first time and illustrated, viz., outline of the foramen magnum; length of the alar canal; comparative presence of the For. alare parvum; proportions of the mastoid process of the temporal bone; shape and development of the pterygoid crest; notch at the rostral end of the facial crest in E. burchelli; different inclination of the caudal end of the zygomatic arch; shape and length of the retroarticular process; relative size of the supraorbital foramina; presence of incisive canals in E. zebra; difference in the junction of the interalveolar border of the mandible with the alveolar border of the first cheek tooth. If three or more differences are used for identification, it should be possible to train any worker to distinguish between the skulls of these two species.