Colorado Insects----Hedgehog Fly

The Spiny Tachina Fly (Paradejeania rutilioides) or as it is affectionately referred to by many entomologist, the hedgehog fly, is found throughout western North America and into Central America.

These large Bristle flies in the family Tachinidae measure up to 3/4 ( or a bit more) of an inch in length and are covered in bristly hairs giving them a superficial resemblance to hedgehogs, earning them their common name. Overall color is black and pumpkin orange, wings are smoky colored and bristles are black.

Our recent trip to Georgetown and Idaho Springs, CO took us well into the range for this fly, that up until spotting it near Clear Creek, I had no idea existed. I must admit I was shocked to see a tachinid fly this LARGE, it was giant in comparison to the tachinid flies I am used to seeing at home in NW Missouri. If you are an entomologists; professional or amateur, and love photography as well, and are faced with something this unusual you almost panic at the thought it will get away without getting a good look at it or preferably a picture of it! I hit PANIC mode as I did my best stealth movements in order to sneak a closer look, only to have it fly away to another plant. This went on for quite some time before it finally got tired or gave up and decided I meant no real threat. Then I noticed two more nearby on the same type of plants. Each fly was nectaring at the bright yellow flowers of groundsel. Locally I now know these flies are very common, but to an out-of-stater this was an exciting find!

This fly is a known parasitoid of the Edward's Glassy-wing moth (Hemihyalea edwardsii). Females will seek out the caterpillars of this species of moth and lay their eggs. When the eggs hatch they will feed on the caterpillar. Tachinid flies are excellent at controlling troublesome insects such as caterpillars, and stink bugs that feed on crops and other agricultural plants of economic importance. They are also secondary pollinators. Their habit of nectaring at flowers makes them excellent transporters of pollen.

My good friend Eric Eaton at Bug Eric
did an excellent write-up about this species as well as another spikey-bottomed fly. Be sure to check it out.

I was fortunate enough to capture several images of this species before it became too dark to allow for decent images. I never tire of finding new-to-me unique insects to observe, photograph and learn about.