Systematics of species of Anthonomus Germar previously assigned to Tachypterellus Fall and Cockerell (Coleoptera: Curculionidae)

Tachypterus Dietz (not Guerin-Meneville) (type species, Anthonomus quadrigibbus Say) and the replacement name Tachypterellus Fall and Cockerell are here considered junior synonyms of Anthonomus Germar (New synonymy). Species formerly assigned to Tachypterellus are now placed in Anthonomus: A. quadrigibbus Say, North America; A. consors (Dietz) (New combination), North America; and A. nodulosus (Marshall) (New combination), Java; A. similans (Voss) (New combination), Java; A. plaumanni (Voss), Brazil; A. collaris (Voss) (New combination), China; and A. dorsalis (Voss and Chujo) (New combination), Japan. A. consors and A. quadrigibbus are considered here to be closely related species; however, their relationships to other species in the genus is unclear. A. consors and A. quadrigibbus are both associated with plants of the family Rosaceae (A. quadrigibbus perhaps also with Cornus sp. [Cornaceae]). Larval development takes place in fruits. A. consors is found west of the Continental Divide in the United States and Canada and is associated with Amelanchier and Prunus species. A. quadrigibbus is widespread in North America on a number of genera of Rosaceae (Amelanchier, Crataegus, Prunus, Pyrus, Malus, and Sorbus species). Variation in structural features, particularly size and size-dependent characters, is marked in A. quadrigibbus and appears largely dependent on size of host plant fruit rather than host plant taxonomic category. No evidence has been obtained to indicate that subspecies or host races should be recognized. A. consors and A. quadrigibbus are hypothesized to have diverged in relatively recent geological time in association with species of Amelanchier to the west and east, respectively, of the Continental Divide in western North America.