Date of this Version
Two species of Xyloryctes occur in the United States: X. jamaicensis (Drury) and X. thestalus Bates. Identification and distribution of these species has long been confused but is reviewed and clarified here. Xyloryctes jamaicensis occurs only in the eastern half of the U.S. and not in the southwestern U.S. as previously thought, while X. thestalus occurs in Guatemala and southern Mexico northwards to the southwestern United States. This hypothesis is corroborated by biogeographical and host plant data. Three new synonyms are listed for X. thestalus: X. faunus Casey 1915, X. hebes Casey 1915, and X. thestalus borealis Endrödi. The decline of Fraxinus spp., the food plant of Xyloryctes species, as a result of damage caused by the introduced emerald ash borer (Agrilus planipennis Fairmaire; Buprestidae) in the United States might portend a similar decline for Xyloryctes species in North America.