Abstract

The distribution of the following Scarabaeoidea (Coleoptera) species in Colorado is established on the basis of preserved specimens and verifiable iNaturalist and literature records: Geotrupes opacus Haldeman, 1853; Onthophagus orpheus (Panzerus, 1794); Digitonthophagus gazella (Fabricius, 1787); Copris fricator (Fabricius, 1787); Copris remotus Leconte, 1866; Phanaeus difformis LeConte, 1847; Boreocanthon probus (Germar, 1824); Aphodius fimetarius (Linnaeus, 1758); Aphodius pedellus (de Geer, 1778); Aphodius (Colobopterus) erraticus (Linnaeus, 1758); Aphodius (Dellacasiellus) kirni Cartwright, 1944; Aphodius (Diapterna) pinguis Haldeman, 1848; Aphodius (Melinopterus) prodromus (Brahm, 1790); Aphodius (Planolinoides) pectoralis LeConte, 1857; Parapsammodius puncticollis (LeConte, 1858); Pleurophorus caesus (Panzer, 1796); Phyllophaga inversa (Horn, 1887); Chrysina gloriosa (LeConte, 1855); Cotalpa subcribrata Wickham,1905; Paracotalpa granicollis (Haldeman, 1852); Popillia japonica Newman, 1838; Euphoria fulgida (Fabricius, 1775); Osmoderma subplanatum Casey, 1915; Dyscinetus picipes (Burmeister, 1847); Orizabus mcclevei Warner, 2011; Orizabus clunalis (LeConte, 1856); Xyloryctes thestalus Bates, 1888; Strategus aloeus (Linnaeus, 1758). Digitonthophagus gazella, Copris fricator, Copris remotus, Aphodius kirni, Aphodius pectoralis, Phyllophaga inversa, Osmoderma subplanatum, Chrysina gloriosa, and Strategus aloeus are new state records for Colorado, the latter two most probably passively transported to the state and not established. The occurrence of the Japanese beetle, Popillia japonica, in Colorado is documented in detail as a result of a state-wide citizen science project. The invasive histories of Digitonthophagus gazella, Aphodius fimetarius, A. pedellus, A. erraticus, A. prodromus, Pleurophorus caesus, and Popillia japonica are outlined. Chemical attraction of several species to common pest lures is discussed and the phenology for all species is established

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