Andrena (Tylandrena) wilmattae Cockerell 1906

= Andrena (Bythandrena) acra Mitchell, 1960: 111 (Michigan holotype; Fig 7C).

Holotype. ♂ USA: Michigan: Kalamazoo Co.: Gull Lake Biol. Sta. (KBS), 9 Jun. 1956, on Crataegus, R.L. Fischer (NMNH: 75167). Synonymy by LaBerge & Bouseman (1970).

County records: Branch, Kalamazoo, Lake, Washtenaw.

Notes. LaBerge & Bouseman (1970) state that this large spring-flying bee is rare in collections but the number of available Michigan records and recent collection of a long series from Illinois (Griffin et al. 2017) suggest that it can be locally numerous.

Material examined. Branch Co.: (no locality) 1 Jun. 1941, R.R. Dreisbach (1 ♂ MSUC) ; Bronson, 14 Jun. 1959, R.L. Fischer (1 ♀ MSUC) ; Kalamazoo Co.: Gull Lake Biol. Sta. (KBS), 9 Jun. 1956 (3 ♂ paratypes (R.W. Hodges) , 1 ♀ MSUC (R.L. Fischer)); Lake Co.: (no locality) 17 Apr. 1955, R.R. Dreisbach (1 ♂ MSUC) .