抄録
The upper dental formula of the Russian desman Desmana moschata (Linnaeus, 1758) (Insectivora, Talpidae) is considered based on the position of the premaxillary suture (sutura incisiva). From the lateral aspect, this suture extends to the second tooth in the tooth row. From the ventral aspect, the suture connects the common alveolus fossa of the second and third teeth in front of the second tooth on the labial edge and behind it on the lingual edge; consequently, the third tooth in the upper row appears to be derived from the maxilla. Therefore, the upper tooth formula of D. moschata may differ from the traditional fundamental dental formula of eutherian mammals (I3, C1, P4, M3), and consist of two incisors, one canine, five premolars, and three molars (I2, C1, P5, M3). This hypothetical view, however, assumes two changes, a tooth deletion in the incisor row and an addition in the premolar row. The significance of the premaxillary suture and possible pitfalls in using it to define dental formulae are discussed.
