Pipistrellus cinnamomeus Miller 1902 Referred to the Genus Myotis

A quiet detective story unfolds in the world of natural history, where two researchers trace a single bat’s identity across a decade of fieldwork. They piece together ten specimens collected from remote Mexican sites—rivers, low‑lying valleys, and coastal towns—each offering clues hidden in skins, skulls, and the tiniest of teeth. By comparing these fragments with the original 1902 description, they reveal how a seemingly ordinary vesper bat was mis‑placed in the wrong genus for years.

The investigation hinges on a subtle dental signature: the relative size of the outer and inner upper incisors. While Pipistrellus typically bears equal‑sized incisors, Myotis displays a noticeably larger outer tooth, a trait that finally settles the bat’s true home. This meticulous re‑examination not only clarifies a century‑old taxonomic puzzle but also showcases the careful, almost forensic work that underpins our understanding of biodiversity.