Lately I have been locked away in our secret laboratory, identifying our dung beetles from a couple projects in the Missouri Bootheel. The specimens are moved from the boxes the have resided in the past couple of years, sorted into groups that roughly look alike, and then run
through a dichotomous key to confirm they are alike or separated. When most people think of dung beetles, they think of scarabs. If you pay attention to the dung you will find that many of the beetles you find will not be scarabs, but will be adapted for a dung lifestyle.
In a previous blog post I talked about the need for the correct key, and because many of the non-scarab dung beetles look like scarabs you will be tempted to run them through scarab keys. A close look at the antennae should keep you safe from falling into a morass of KEY FAILURE, where nothing works. Among the non-scarab dung beetles are Hydrophilids, or water scavenger beetles. These ‘dung beetles’ have a major distinction that makes them different from the scarab dung beetles – they are predatory as larvae (but this feature never shows up in any key – thank goodness). I know you have always thought of a piece of poo as tranquil, nice place to raise up a brood of kids, and I hate to ruin this idyllic notion, but predators run rampant in this environment. The hydrophilids in poo are beneficial because they help control fly populations, which came be a problem in livestock production.
A favorite poo hydrophilid is Cercyon quisquilius. Carl Linnaeus, a botanist, (and the first modern taxonomist) initially named this species Scarabeus quisquilius putting it firmly in the family Scarabaeidae, because the family Hydrophilidae didn’t yet exist. As our understanding of these beetles grew, so did our taxonomy. As I work with these beetles, my understanding of their roles, my appreciation of their innate grooviness, and realization that a poo is not a nice place to live increases.