Bess beetle

Bess beetle

Passalus interruptus



These beetles can produce 14 different sounds by rubbing parts of their bodies together; this is called stridulation. No other insect is known to produce so many different sounds. They squeak if disturbed or angry and their noises appear to help put off predators. There are calls between adults and their young and range of sounds associated with courtship.

Where can you see them?

Bess beetles are a family of beetles that are found mostly found in the tropics. They are commonly found in rainforests because they really like rotting hard woods. They live in family groups, grubs and adults together inside rotting logs.

What do they eat?

Both mum and dad help care for their young.  Adults chew galleries in the wood and feed chewed pulp to their young. They have special fungi that live in their guts that help break down the tough wood. Adults pass this fungus to their young by feeding them their own ‘frass’ (insect poo).

Why are they important?

Adult bess beetles are very important in recycling nutrients from wood. They can process 4.5 times their own body weight in wood a day, which makes the wood’s nutrients available to the living rainforest plants for their own growth.

More images and video of Bess beetles: