Tiphiid - Paratiphia robusta

Size does not matter very much...

For many hunting wasps. Sometimes the ordinary prey seems disproportionately stronger and better armed than its wannabe hunter, yet this latter somehow manages to subdue it.
One of the most stiking examples of this exists in this same Tiphiid family (subfamily Methocinae).
The small apterous, ant-like female of European Methoca ichneumonides paralyzes nearly full-grown Tiger beetle larvae by stinging them on the underside of their... mourhparts! Ironically, the formidable mandibles of the predatory larva are TOO LARGE to efficiently seize its pygmy foe, who litterally slips between them.
BTW, thanks for sharing such good pictures of North Western Hymenoptera.

… Richard Vernier, 6 November, 2007 - 8:52am

It's amazing

to me how so many of the wasps have adapted with small advantages to use in brinksmanship against the most lethal of predators. It makes sense that small is better against tiger beetle larvae...they look like they've got some wicked jaws. I thought about the possibility of small host/small adult from some reference I can't remember now... might have been buried somewhere in Kevin O'Neill's Solitary Wasps - Behavior and Natural History - in which the size of some wasps were dependent on host size. O'Neill mentioned Pterombrus as using cicindela as its host... I haven't been able to find any reference anywhere to that tiphiid. I'm supposing it's a wingless female?

… Fred Bentler, 6 November, 2007 - 10:45pm

Probably Paratiphia.

The genus here is probably Paratiphia, very common in eastern WA and OR. In fact, P. robusta is one of the more common species:-)

… Eric R. Eaton, 6 November, 2007 - 11:47am

Tiphiid

I took a specimen and would be happy to send it your way if you're interested.

… Fred Bentler, 6 November, 2007 - 11:13pm