Eudioctria tibialis is in the same subfamily as Echthodopa. They are not common in AR and only found in a few SW counties. Norm took this shot in Polk county in June. They look like fat Cerotainia or little odd Atomosia. There are two other extensive eastern species of Eudioctria which occur as close as Tennessee.

Eudioctria from Ohio from Jay Cossey. A male and it could also be tibialis but not clearly the same species. Ohio does not have a tibialis record. It does have records for propinqua, albius and brevis. I am not decided from this photo yet.