A beetle with a double stinger

Stings are the specialty of scorpions and Hymenoptera; however, one species of beetle – a longhorn (Onychocerus albitarsis) appears to be muscling in on the act. What’s really interesting is that this beetle stings with its antennae, both of which bear sharp points that are jabbed into an unsuspecting enemy. The ‘venom’ delivery system is also very similar to that of scorpions, which makes it another really good example of convergence.

In humans at least the sting of this beetle causes cutaneous and subcutaneous inflammation, à la:

 

It’s not exactly clear what the sting is delivering to cause this inflammation. Is it an endogenously produced venom or something assimilated from the hostplants of the larvae as they develop in wood. Some of the congeners of this beetle have been reared from trees with irritating saps or resins. 

Figuring this out may be difficult as this appears to be a very rare species, but with some luck maybe we’ll find one or two when we’re at Los Amigos in Peru soon.

The original paper by Berknov et al that describes this fascinating adaptation is here. Do take a a look.