LAUSR

Abstract A new species of Xenosaurus in the X. tzacualtipantecus clade is described from the Sierra Madre Oriental of northern Puebla, Mexico. The new species differs from all of its congeners in possessing a unique combination of characters. The new species appears to be allopatric and fills in the geographic gap between the geographic distributions of X. tzacualtipantecus and the species in the newmanorum clade to the north and northwest and those of the species in the grandis and rackhami clades to the south and southeast. The new species occurs between approximately 880 m and 1470 m of elevation, and appears to be restricted to cloud forest, which has been replaced by coffee plantations in many areas. An updated key to the species of Xenosaurus is provided.