Harlequin beetle

Harlequin beetle

Acrocinus longimanus


This beetle is male. You can tell because the males have the longest front legs. Males must compete to guard the best rotten trees. Those with the best trees have the best chances of meeting a mate. The beetle battles can involve head-butting, biting and/or throwing each other off the tree they are fighting over. The males with the longest and best-shaped front legs usually win.

Where can you see them?

Southern Mexico down to Argentina and across to Trinidad in the Caribbean. You are most likely to see them flying at night looking for dead trees or at other times of day guarding or laying eggs on the rotten wood they have found.

What do they eat? The adults are attracted to the milky smelly sap of freshly dead fig, mulberry and dogbane trees. The adults eat the tree sap and using their mouths, dig holes in the wood which they then lay their eggs in. The grubs that hatch feed in the rotten wood forming large tunnels.

Why are they important?

Harlequin beetles are very important in recycling forest nutrients. The way they feed on freshly dead trees makes it easier for many other species to move in and feed too. One of the mini beasts that likes wood that has been infested by harlequin beetle grubs is a pseudoscorpion. These tiny creatures hitch rides under the wings of the adult beetles from rotten tree to rotten tree.