Abstract
Four Palaearctic species of Staphylininae (Coleoptera: Staphylinidae) are reported from North America for the first time: Heterothops cognatus Sharp, H. praevius (Erichson), Philonthus chujoi Dvořák, and Quedius (Raphirus) maurorufus (Gravenhorst). We suspect that these species are part of a more recent cohort of accidental introductions to North America. Notably, two of them are native to the East Palaearctic, an unusual source of adventive staphylinids in North America because nearly all others are native to Central Europe. We suggest that the East Palaearctic is an underrecognised and increasingly important source for recently adventive soil invertebrates and that increased taxonomic focus on this fauna is important to North American biosecurity. The detection of trans-Palaearctic H. praevius resulted in the recognition of H. praevius Erichson (= H. marmotae Smetana syn. nov.). We also newly report the Nearctic species Heterothops conformis Smetana and H. sordidus Smetana from eastern North America. Philonthus debilis, a close relative of P. chujoi, is reported from the Yukon Territory, representing the northernmost locality known for this long-established adventive species. Illustrations of diagnostic features, barcode data, and distribution maps are provided for all four species. Updated or new identification keys are provided to aid in the recognition of these species in eastern North America.