By A Mystery Man Writer
The horned passalus belongs to a family of beetles called Bess beetles or patent leather beetles. It’s the only species in the family that lives in Missouri. Bess beetles are black and shiny (like patent leather), and have one lengthwise groove on the pronotum (shoulderlike area between head and wing covers). There are lengthwise grooves on the wing covers, too. The antennae are not elbowed. The horned passalus has a forward-pointing horn on its head and lives in colonies, with the larvae, in well-rotted wood. Adults and larvae communicate by rasping noises, made by rubbing parts of their bodies together. They often stridulate (make the rasping sound) when picked up, overturned, or otherwise harassed. The larvae are whitish grubs that live in rotting wood. The heads are brownish, and it looks like they have two pairs of legs (the hind pair is shorter and used to make raspy sounds). They look a lot like the larvae of other beetles.
EENY 487/IN879: Horned passalus, Odontotaenius disjunctus (Illiger
Horned Passalus Missouri Department of Conservation
Horned Passalus Missouri Department of Conservation
Ecology and Conservation of Passalidae
10 Fascinating Facts about Bess Beetles, beetles
Springfield Plateau: October 2017
Springfield Plateau: October 2017
Stag Beetles (Lucanids) Missouri Department of Conservation
horned passalus - Odontotaenius disjunctus (Illiger)