New host record of Dahlibruchus Bridwell, 1931 on cultivated Dahlia Cav. in Mexico and description of two new species (Coleoptera: Bruchidae)

Dahlibruchus Bridwell is a genus in the family Bruchidae (Coleoptera: Chrysomeloidea) and all species have as host plants species in the genus Dahlia Cav. (Asteraceae). Usually they arrive on hosts when flowers appear and start feeding on nectar and pollen; later females lay eggs on bracts, and a few weeks later the adults emerge. Presently, the genus Dahlibruchus < i>contains three species. The description of two new ones (Dahlibruchus castroi, new species and Dahlibruchus ruizi, new species) brings this number to five. A key to all species is presented. Dahlibruchus conradti Bridwell is recorded for the first time on cultivated dahlias in the country of Mexico.