Friday Beetle Blogging: Lutrochus Travertine Beetle

Here's an odd sort of beetle of whose existence I was entirely ignorant until a few showed up in our lab. My primary research these days is with the Beetle Tree of Life group, and the travertine beetle is just one of many Coleopteran wonders I've been introduced to over the past couple of years.  This one is especially cute.

These little guys are aquatic, clinging to rocks in fast-moving streams. They're rather picky animals and not just any rocks will do. They need a particular kind of limestone called Travertine.  The long tarsal claws- somewhat visible at left in the photo above- help the beetle maintain a toe hold against the flow, and the fine coating of velvety hairs traps a bubble of air so that the beetle never actually gets wet.