Identifying slim, black tachinids with grey dusting

I always seem to have difficulty identifying the slim black&grey tachinids in the tribe Blondeliini and Phyllomya volvulus in photos. This mini article is a work in progress but should give some clues and rules of thumb that might be useful:

Phyllomyia volvulus: orange/yellow wing bases/calyptrae; long & strong abdominal bristles, often longer than […]