I got a shipment of 15 blue death-feigning beetles (Asbolus verrucosus) yesterday from Bugs in Cyberspace. If the goal of the lab is to study the biology of the local wildlife of the semi-arid savannah, why would I be interested in Asbolus, a creature from the hot, dry Sonoran and Mojave deserts? Well, aside from them being cute, lumpy, blueish, and acting like they are dead (see below), their biology is worth a look. Compared to the local species of Eleodes and Philolithus, Asbolus is adapted to much more extreme conditions, with scarce resources and high temperatures. One reported adaptation for these difficult conditions is a much lower metabolic rate than those I have measured for Eleodes and Philolithus. However, the experiments were done long ago and under different conditions. When I saw that these guys were available online, it seemed like an excellent opportunity to revisit their oxygen consumption and temperature sensitivity.

Tenebrionid beetles, like Eleodes, Philolithus, and Asbolus, employ thanatosis, or playing dead, as a defensive strategy. With Eleodes and Philolithus, I am accustomed to them freezing for a while during handling, but it is not particularly convincing. Most of the time they try to wiggle away rather than playing dead.

Asbolus, on the other hand, lives up to its name of death-feigning beetle, and fakes its own death at every opportunity. Whenever they are handled, they turn over and stick their legs out like cartoon characters, and will do so repeatedly. This may be their only choice. They have no defensive stink glands (like Eleodes), nor do they mimic a stinky species (as Philolithus mimics Eleodes), so playing dead may be the most effective strategy.

They will need to settle in for a few weeks before experiments get started, and the real test will be in the summer when all of the local beetles have their metabolisms at full throttle.