They're imports but they are here. Common according to the sources I googled. I've seen them about including a heap of larvae hitting the food in my compost and I didn't know what they were at the time.

Have you read, it was a couple years ago, a 90 page submission for cleaning the wastes of some Brazilian city using BSF?

I think they thought he was mad. Visionary he was, albeit, obsessively passionate. 90 pages!

I'm mad too, I read it all.