Let me introduce you to Chrysops, and Haematopota
I quote from Alan Stubbs and Martin Drake* .
“It may sound a contradiction that an insect with ugly habits should be beautiful. However, to really appreciate that statement, look at the eyes of a live horsefly. The colours can be extraordinary– brilliant green or bronze in Chrysops ”
These ladies ( only females need blood to lay eggs) were biting my arm. Only females bite, and each did hang on until I got a photograph and then I dispatched her. Chrysops is an insect of wetlands “chrysops (larvae) appear to feed on decaying matter”*
*British Soldierflies and their Allies, Stubbs and Drake