New Species of Mud Turtle (Testudines: Kinosternidae) from the Tres Marías Islands, Nayarit, Mexico

Abstract

The mud turtles in the Islas Tres Marías archipelago, off western Nayarit, are one of the earliest known Kinosternon populations from Mexico, with discovery dating from the late 19th century. Though known for almost a sesquicentennial, the identity of the species there was originally confused in a nearly century-long serial fluctuation that vacillated between that of K. integrum and
that of K. hirtipes. This taxo-nomenclatural history is fully reviewed here, and following the neotype designation and sensu stricto redefinition of Kinosternon integrum LeConte, 1854 by Joseph-Ouni et al. (2025), these insular mud turtles were investigated from a taxo-morphological perspective. They are described here as constituting a distinct new species in the K. integrum complex based on a suite of morphometric, morphological and colorimetric characters. The origin of these mud turtles is believed to be vicariant, as no evidence of human introduction is apparent. As no suitable habitat exists on the remaining islands, the new species is endemic solely to Isla
María Madre, joining a long list of endemic vertebrates from this spectacular hotspot of biodiversity.