A new species of Dichotomius Hope is described based on specimens from states of Yucatan and Quintana Roo, Mexico. Dichotomius maya n. sp. is included in a new key to species of the carolinus group, which comprises besides new species described herein, the following species with North American and Central American distribution: D. carolinus L., D. colonicus (Say), D. annae Kohlmann & Solís and D. amicitiae Kohlmann & Solís.
Scarabaeinae; Yucatan Peninsula; tropical forest