Dental abnormalities in Myotis riparius (Chiroptera, Vespertilionidae), with comments on its evolutionary implications

The study of tooth morphology is fundamental for the taxonomic and evolutionary comprehension of mammals. However, dental abnormalities can lead to misidentifications and species invalidations. We present two distinctive dental anomalies observed in Myotis riparius: (i) hypodontia, characterized by the absence of the second upper premolar (P3) on both sides of the dental arch in an adult male from Panama, and (ii) polyodontia, characterized by the presence of three upper incisors on one side of the dental arch in an adult male from Brazil. We discuss the genetic and ecological bases of these anomalies and the importance of these case reports for understanding the evolutionary developmental biology of bats.