Not Quite Bees

Here's another take on last night's theme:

Systoechus vulgaris, Illinois Beach SP, Lake Co, IL  7/12/2013

This lovely creature (if you're another one, I suppose) is a Bee Fly (family Bombyliidae), specifically Systoechus vulgaris. While that proboscis looks pretty ferocious, this little critter feeds strictly on nectar and pollen, hovering in front of flowers and looking very bee-like.

Well, it only eats nectar and pollen now -- it used to be a predator of grasshopper eggs! (1)

This is a fairly diverse family, with over 5,000 species spread over 15 subfamilies. (2) Here's a couple more:

Hemipenthes edwardsii, Cimmaron NG,
Morton Co, KS 5/24/2013

This one is Hemipenthes edwardsii.

Villa arenicola, Lyons Woods FP, Lake Co, IL 7/25/2013

And this is Villa arenicola.

Both of these are parasitoids, with females laying their eggs on unsuspecting insects so that their offspring will have a ready-made meal that should last them until they grow up. Hemipenthes, though, is even cooler than that -- in some cases the insects it parasitizes are themselves parasites, specifically certain wasps and sawflies! (3)

It seems odd, perhaps, that such sinister little kids should grow up to be flower-sipping adults. But biology is good at making us see that odd is very much about your point of view.

(1) Berg, V. L. (1940). The external morphology of the immature stages of the bee fly, Systoechus vulgaris Loew,(Diptera, Bombyliidae), a predator of grasshopper egg pods. The Canadian Entomologist, 72(09), 169-178.

(2) http://bugguide.net/node/view/185

(3) Yeates, D. K., & Greathead, D. (1997). The evolutionary pattern of host use in the Bombyliidae (Diptera): a diverse family of parasitoid flies. Biological Journal of the Linnean Society, 60(2), 149-185.