Swift Feather-legged Fly

Hairy legs - Wikipedia

I followed this little guy in our back yard as it darted from flower to flower, skimming the surface like a typical pollinator.  Even without magnification I could see the the large headlight eyes of a fly.  INaturalist identified it as a swift feather-legged fly- Trichopoda pennipes.  This view on the right shows how it earned its "feather-legged" name.

"These medium-sized flies have a velvety black head. The velvety black or brown thorax shows a few yellow stripes. Eyes are large brown with yellow between. The color of the slender abdomen varies from bright orange to completely black."  INaturalist

 

While they are feeding on nectar of flowers such as Queen Anne's lace, they are also on the search for insects to raise their young. They will deposit a few eggs on squash bugs, stink bugs and leaf-footed bugs.

"When the eggs hatch, the larvae burrow into the bug. If there are several larvae in one host, only one survives. After feeding on the bug's tissues, the cream-coloured larva emerges and falls to the ground where it pupates in a reddish-brown puparium formed from the last larval skin. The bug meanwhile dies. After about two weeks, an adult fly emerges from the pupa. After mating, a female fly may lay several hundred eggs in total. There are up to three generations of the fly each year and the parasitoid overwinters as a second instar larva within the body of the overwintering host,"  INaturalist.    

Egg on green stinkbug head- Wikipeida

Old feather-leg is a gardener's friend, laying eggs on a wide variety of plant pest species.  There are different biotypes across the United States, preying on different hosts in different regions.  On the southern green stink bug, the rate of parasitism can be as high as 93% and up to 80% on the squash bug.