Identification
Scientific Name:
Passalus sp.
Common Names:
Bess beetle, bess-bug, betsy-bug, horned passalus beetle, patent-leather beetle, passale

Classification
Class: Insecta
Order: Coleoptera
Family: Passalidae
Genus: Passalus
Species: There are about 300 species in the New World

 

Habitat
Beetles of the Passalidae family live mainly in the tropics in the Old and New Worlds. In wooded regions, any damp, rotting log or tree stump is likely to be home to one or two bess beetle colonies.

Profile
Larvae and adults live together in a network of galleries dug in the wood of rotting trees, forming tiny colonies that show some social organization-a very rare trait among beetles.
 
Both larvae and adults emit a variety of audible signals, associated with a number of particular behaviours-aggression, or courtship behaviour to win a partner of the opposite sex.
 
Bess beetles are also notable for the way they care for their young. Both parents take turns feeding the larvae rotting wood that they have already chewed and broken down with their own saliva.

Adults stridulate by rubbing roughened areas on the underside of the wings against their abdomens. The squeak they make is clearly audible to the human ear. The sounds made by larvae, by rubbing their hind legs against their abdomens, are harder to hear.
  

Larvae and adults eat not only rotting wood, but also their own excrement. In so doing, they transmit the intestinal parasites they need to help them digest wood cellulose.
  

Despite their size and strong mandibles, bess beetles do not bite. When disturbed, they show their displeasure with a series of squeaks!