Whirligig Mite

I should probably also add two comments. First, there actually is a spider mite common on concrete and picnic tables... it's called a clover mite (Bryobia) and looks quite different. See images here:http://bugguide.net/node/view/219196/bgimage. Second, there is another group of mites often mis-named "red spider mites" that are not at all a spider mites... they are called concrete mites, and are in the family Erythraeidae, genus Balaustium. Like whirligig mites, they are bright red and can be fast, but they look quite different. Compare with these images: http://bugguide.net/node/view/91443/bgimage.

Hey Phil, no problem. Mite identification is not easy and frustration is inevitable. Nearly all mites cannot be identified from a blurry photograph, and those that can often to look similar. Nevertheless, there are some definitive clues in this case. First, you said the mite was "quite fast", automatically dismissing nearly all spider mites (Tetranychidae) which you should think of as slow cows browsing on plant material. "Quite fast" should make you start thinking predator. After all, you need to be fast to chase down prey. Second, bright red, not "furry", and that size (nearly all tetranychids are much smaller) automatically narrows the possible identifications greatly. Given it was found on a picnic table in an urbanized area of Ohio and not in an understudied old grow forest, common mites are more likely than weird ones... narrowing initial guesswork further... Then you come to the nearly triangular body, truncated at the posterior, combined with strong latigrade legs that seem to radiate from a central point. Throw in the fast erratic running behavior and that it was found off of the ground and you have excellent diagnostic characters for the genus Anystis (whirligig mites). Compare with images here: http://bugguide.net/node/view/94328/bgimage. Here is an image of a reddish spider mite for comparison: http://bugguide.net/node/view/741417/bgimage. Let me know if you have more questions. I hope this was helpful.

This is not a herbivorous spider mite (family Tetranychidae) but a whirligig mite (Anystidae: Anystis), which are predacious.