This is a hefty bombyliid that apparently is brood parasitic on a Sand Wasp, Steniolia scolopacea. It collects sand grains for bombing runs on the wasps' burrows; it also flies around with them, occasionally getting chased by the females (not the males -- they're passive), but always eluding them, which is interesting because the female wasps are voracious predators of another, smaller, bombyliid species which they hunt and capture in the surrounding woodlands.

I am creating a gallery with pix of the whole cast of players and need an ID for this bee fly: it is largish, all black, does not show its proboscis like most other bombyliids I am familiar with (locally about 15 spp now); behavior as described above.

Believe this is a female because it was active in the wasp burrowing area. Genus/sp?

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