Mydas fly

Description:

Large black fly with red/orange mark on top (dorsum) of 2nd abdominal segment. Body hairless, cylindrical. Eyes large. Antennae are distinctively clubbed in the Mydidae. This species flies rather boldly in the open. With the black-and-orange pattern, it resembles a wasp and fools the casual observer. (information from BugGuide)

Habitat:

Garden in a City park

Notes:

I watched this fly carry on a territorial battle with an eastern cicada killer wasp for a few minutes. The wasp was buzzing through, looking for a suitable site for digging her brood chambers (I presume), and each time she flew through the fly's area, the fly would give chase. The wasp eventually left and was seen checking out an area nearby.