Remarkable Mimicry: Fly as Wasp

 

A huge - compared to other common wasps, but maybe not an elephant - spider wasp, Entypus unifasciatus, takes nectar from the flowers of a Rattlesnake-master, Eryngium yuccifolium.

ASIDE: Rattlesnake-master lures pollinating insects like few other plants. And it is quite showy with numerous ball-like inflorescences of snowy-white flowers and its odd leathery yucca-like foliage. It grows easily in gardens and is a fantastic addition to anyone's yard. And Rattlesnake-master is readily available in the nursery trade, at least among nurseries that make an effort to peddle native flora.

I spent a fair bit of time at Chaparral Prairie State Nature Preserve on August 5, which was at its peak of botanical glory. See some photos of the prairie RIGHT HERE. The Rattlesnake-master was in nice condition, and I probably could have spent all day stalking and shooting the myriad pollinating insects visiting its flowers. As it was, I did manage to photograph a number of them, perhaps highlighted by this huge wasp.

Entypus unifasciatus is one of the spider-hunting wasps and is impressive by any hymenopteran standard. It is an edgy beast, active and constantly twitching its wings with rapid flicks. This species specializes on large wolf spiders (female wasps do the hunting and stinging), and an insect has to be tough to take one of these venomous eight-legged behemoths down. I have seen the wasp vanquish spiders a few times, such as HERE, and HERE.

From my limited experience, the spider is no match for the wasp. The latter darts in and administers a punishing, paralyzing sting in the blink of an eye. The wasp's venom must be a potent brew indeed, and I suspect its sting would pack a punch to a person, too. Fortunately, they are not aggressive and short of grabbing one with your hand, it'd probably be nearly impossible to get stung. However, inquisitive birds might have to learn this lesson the hard way. Except for Summer Tanagers, which specialize in capturing and eating large bees and wasps.

Well, what do we have here? I made this image in the same area as the preceding spider wasp, on the same day. And, while completely unrelated, this insect bears a remarkable resemblance to the large stinging wasp. It is just as big, too.

This is a mydas fly, Mydas tibialis, which is completely impotent as far as having any ability to inflict pain. The big fly is visually intimidating though, and most people - and more importantly birds, presumably - would leave it be. The fly even nectars at the same flowers favored by the wasp.

The fly world is awash in amazing mimicry such as this. Flies that can mimic the appearance of bees and wasps that can inflict stings must gain some measure of protection from visual predators like birds, who will learn to avoid certain insects such as those whose appearance they mimic.