Subject: Black bug
Location: Gunnison, Colorado
July 21, 2014 5:08 pm
I found this bug in my home. I thought it was a bee at first but then with a closer look it seemed to be an oversized fly. I looked up horseflies but the bug I found had widest eyes. What is it?
There is enough detail in your images for us to determine that this is a Bot Fly in the genus Cuterebra, the Rodent Bot Flies, but we haven’t the necessary skills, and we suspect there is not enough image detail for even an expert to determine a species identification. You can compare your image to this individual from BugGuide that also is identified only to the genus level. According to BugGuide: “Females typically deposit eggs in the burrows and “runs” of rodent or rabbit hosts. A warm body passing by the eggs causes them to hatch almost instantly and the larvae glom onto the host. The larvae are subcutaneous (under the skin) parasites of the host. Their presence is easily detected as a tumor-like bulge, often in the throat or neck or flanks of the host. The larvae breathe by everting the anal spiracles out a hole (so they are oriented head-down inside the host). They feed on the flesh of the host, but only rarely does the host die as a result.”