The Tiny Bark Clown

Another trip into Cambridge today and I managed another walk along the river and had another poke around some of the dead wood. Not huge numbers of beetles but may have to start looking at centipedes given the number and apparent diversity. They seemed to be everywhere today.

I picked up a few staphs and found a single carabid, a Pterostichus vernalis, under bark from mainly poplar again. I was hoping to find the rather odd looking Hololepta plana that apparently prefers dead poplar and is definitely about, but so far no luck.

a fallen poplar branch 

I pootered something tiny that I initially thought was a mite but which didn't look quite right. Once home I stuck it under the microscope to find that it was indeed a beetle. And a tiny one at that, at only 1.5mm. Shiny, globular and glabrous with dispersed punctures and no obvious scutellum. I was slightly uncertain as to a family...

...until I flipped it over to reveal a classic histerid rear end and fore leg.

Pulling the recently published Histerid book off the shelf gave me another chance to use the new key. Once again getting it to species was simple and straight forward. A combination of size, shape, a 5-segmented rear tarsi and a right-angled fore leg (obvious in the image above) makes this Abraeus perpusillus, another new species for me.

This is a species of parkland and pasture woodland and is found in dead standing and fallen deciduous trees, preferring oak, ash and beech. But has been found in a wide range of species. It's widespread across England and Wales and is thought to be a predator of mites.

In the new book it has been given the rather lovely name of The Tiny Bark Clown and is certainly the smallest histerid I've come across so far.