Map of northeastern North America with relative bee species richness. The number of bee species reported for Pennsylvania (this study), and neighboring provinces and states, is shown: Connecticut (Zarrillo et al. 2016), Maine (Dibble et al. 2017), Maryland (North American Native Bee Collaborative 2017; Sam Droege, pers. comm.), Michigan (Gibbs et al. 2017a; Jamieson et al. 2019), New York (Danforth and van Dyke 2015; Ascher et al. 2014), Ontario (Sheffield et al. 2017; Bees of Canada 2020), and West Virginia (McKinney 2016).