Our insect of the week for September 15, 2025, is Epicauta pensylvanica (De Geer, 1775). [COLEOPTERA: Meloidae]. Yes, there is a single “n” in the final part of the species name. That is how the original territory was spelled a long time ago. Once a species name is formally described, it remains with that spelling forever. This species is classified in the same family as the species we examined last week. It is commonly called the black blister beetle. This species is found in North America and is native to central Illinois.

Adults are often observed in mid to late summer in central Illinois. Their life history is similar to the species we examined last week. In case you did not know, beetles in this family experience hypermetamorphosis.The larvae experience several distinct larval forms (especially the first instar larvae called triungulins which are much more mobile than subsequent instars).

The insect in this photograph was collected by Mark DuBois in Tazewell County, Illinois nearly 50 years ago. The image was generated by stacking multiple photos together to make this high resolution composite image.