Prostoia similis (Hagen) .

This species is known from all states adjacent to Illinois except Iowa (Heimdal et al. 2004; DeWalt et al. 2010), but had never been recorded from Illinois. Examination of INHS material revealed the first Illinois record for this species.

IL, Pope Co., Lusk Creek, 5.5 km WSW Herod, 37.56775, -88.49938, 4/19/1994, D.W. Webb, 15♀ (INHS) .