A review of the Augochloropsis (Hymenoptera, Halictidae) and keys to the shiny green Halictinae of the midwestern United States

Abstract

Augochloropsisand other shiny green Halictinae have had various taxonomic issues and are often misidentified. One prevailing taxonomic issue is thatAugochloropsis metallica(Fabricius) has two subspecies, that have long been recognized as morphologically distinct (Augochloropsis metallica metallicaandAugochloropsis metallica fulgida(Smith), but the subspecies are inconsistently applied in the literature. Here, we review theAugochloropsisof the Midwest and further address theAugochloropsisspecies in the broader United States to resolve the outstanding taxonomic issues with the midwestern species. We provide identification keys and diagnoses for the genera and species of the shiny green Halictinae of the midwestern United States, which includes the generaAgapostemon,Augochlora,Augochlorella, andAugochloropsis. This work results in taxonomic changes toAugochloropsis.Augochloropsis sumptuosa(Smith) is split into two species, with the nameAugochloropsis sumptuosaretained for the eastern form, andAugochloropsis humeralis(Patton),stat. nov., reinstated for the western form.Augochloropsis metallicais split into five species, with two of those species occurring in the midwestern United States:Augochloropsis metallicaandAugochloropsis viridula(Smith),stat. nov.Examination of the holotype ofAugochloropsis fulgida(Smith) revealed that it does not agree with the prevailing concept ofAugochloropsis metallica fulgida; it is reinstated asAugochloropsis fulgida,stat. nov., but is currently known only from the holotype female from Florida.Augochloropsis cuprea(Smith), long considered to be a synonym ofAugochloropsis metallica, is also distinct, and we are reinstatingAugochloropsis cuprea,stat. nov., though the range of this species is unclear. We further recognizeAugochloropsis fulvofimbriata(Friese),stat. nov., from South and Central America, as distinct. These changes result in a total of threeAugochloropsisspecies in the Midwest and seven named species in the United States. We are aware of additional species from the southern and southwestern United States that are undescribed, and we highlight additional taxonomic work that remains to be done.