We describe here a novel achlorophyllous parasite on the roots of Hedyosmum mexicanum C. Cordemoy (Chloranthaceae) as a new genus and species, Eremitilla mexicana Yatskievych & J. L. Contreras. The new taxon is currently thought to be endemic to the state of Guerrero, Mexico. It is best classified in the Orobanchaceae, but differs from other members of the family in having 5-ribbed, muricate ovaries containing five parietal placentae, as well as unusual stamens in which the anther is partially embedded in an expanded filament apex. Within the Orobanchaceae, the new taxon is probably related to a group that contains the other American holoparasitic genera. Morphologically, Eremitilla Yatskievych & J. L. Contreras displays a number of autapomorphies, but few identifiable synapomorphies. This presumed relictual taxon presently is known only from a restricted habitat and a very small geographic range, and thus is of conservation concern.