105: Southwestern Stag Beetle

So there’s not going to be any artwork of today’s animal, because I spent a bunch of time drawing a Harvester Ant before remembering that I wrote about them in newsletter #49.

How about those Southwestern Stag Beetles though??? They live in western and southwestern Colorado (surprise). Stag beetles are distinguished by the males having enlarged mandibles – the eastern stag beetle, which does not occur in Colorado, can have mandibles the same size as the rest of their bodies! They use these mandibles for fighting – sometimes over potential mates but also over food sources. Although they look dangerous, they are not aggressive towards humans. The larvae of this species are pale colored grubs who live in rotting wood.

There are around 1200 species of stag beetles (also known as scarab beetles), and the earliest known is a fossil from the Middle Jurassic (ca. 166 to 163 mya) found in Mongolia.