Bee-like Robber Fly

My friends laugh at my "detail" nature. My long answer was for reference since I am not an expert. :)

bayucca; checked your request and your suggestions. Here is what I know from references (With the genus Laphria, the pattern of black and yellow is key to identification): Laphria flavicollis is a medium-sized robber (some individuals are quite small) all black except for the yellow mystax and the very furry yellow thorax. There is some yellow hair on the legs. The abdomen is bare and shiny black. (your spotting's abdomen is not bare or shiny and it has yellow sideburns) Laphria virginica thorax is fuzzy and yellow, abdomen is all black. "Beard" is yellow, and "sideburns" also yellow, not black as in L. thoracica. L. grossa is similar, but has yellow on the abdomen and is much plumper. (your spotting's abdomen has yellow) Laphria grossa. As the name implies, it is a large robber, the size of the biggest bumble bees, which it imitates quite well, the long black sheath for the beak somewhat spoiling the effect. On this species the mystax is yellow, the thorax is yellow, and most of the abdomen is yellow. Note especially the little fan of yellow hairs in front of the bright yellow haltere at the base of the hind leg. The main population of this species is east of the Mississippi River. (your spotting has the yellow fan as well as the other features) My photo does not show the features well for Laphria grossa, but many have been reported on the Louisiana diptera blogs this spring. Bugguide notes that the amount of yellow on the abdomen changes with range. That may be an explanation of why your spotting is not a robust yellow, but more stripes of yellow. I hope this answers your question. :)