Classification of Tertiary fossil Donaciinae of North America and their implications about evolution of Donaciinae (Coleoptera: Chrysomelidae)

Abstract

Specimens of Donacia primaeva Wickham from the Oligocene Florissant shales of Colorado are indistinguishable from male specimens of the extant species Plateumaris nitida (Germar), and are assigned to the P. nitida group. A fossil from the Late Paleocene Paskapoo Formation of Alberta (Donacia wightoni n.sp.) is the oldest fossil of Donaciinae, assigned to Donacia (Donacia), an ecologically and structurally highly derived subgenus. Both species are assigned to small groups of extant species which are not the most primitive Donaciinae. They are similar to extant taxa, which suggests they have maintained considerable structural stasis over a long period of time.