Epeoloides pilosulus (Cresson 1878) is one of the rarest bees in North America with only a handful of records since 1960. The last collection in Michigan was made in 1944. Epeoloides pilosulus is a brood parasite of Macropis bees, which until recently had not been collected in Michigan for several decades. Bee surveys in Midland County, Michigan have led to the rediscovery of E. pilosulus in this state – the first record in 74 years. Michigan becomes the fourth state where E. pilosulus has been rediscovered after Connecticut in 2006, New York in 2014 and Maine in 2016, and the sixth region in North America after Nova Scotia in 2002 and Alberta in 2010. State-wide bee surveys have also shown that the principal host, Macropis nuda (Provancher 1882), remains widespread in Michigan, and that Macropis patellata Patton 1880 is newly recorded for the state.
Wood, Thomas J.; Killewald, Michael F.; Graham, Kelsey K.; Gibbs, Jason; and Isaacs, Rufus
"Epeoloides pilosulus (Cresson) Rediscovered in Michigan, with Notes on the Distribution and Status of its Macropis hosts.,"
The Great Lakes Entomologist, vol 52
Available at: https://scholar.valpo.edu/tgle/vol52/iss1/4