Sphecid Wasps - Ammophila sp.

Live adult thread-waisted wasp photographed at Winfield, DuPage County IL June 20, 2005. This wasp was photographed late in the evening, in its sleeping posture. The wasp clamps onto a twig with its mandibles and remains immobile all night thus.

Sphecidae (Latreille, 1802) is a cosmopolitan family of wasps that include digger wasps, mud daubers and other familiar types that all fall under the category of thread-waisted wasps. Both of the traditional definitions of the Sphecidae (the conservative one, where all the sphecoid wasps other than ampulicids and heterogynaids were in a single large family, and the more refined one, where the 7 large sphecid subfamilies were each elevated to family rank) have recently been shown to be paraphyletic, and the most recent classification is closer to the conservative scheme; the families Heterogynaidae and Ampulicidae are the sister taxa to what are now two families (instead of one), the Sphecidae and Crabronidae. Thus, the bulk of the sphecoid wasps are now placed in Crabronidae, and Sphecidae per se is a much more restricted concept, equivalent to what used to be the subfamily Sphecinae.

The biology of the Sphecidae, even under the restricted definition, is still fairly diverse; some sceliphrines even display rudimentary forms of sociality, and some sphecines rear multiple larvae in a single large brood cell. Many nest in pre-existing cavities, or dig simple burrows in the soil, but there are also species which construct free-standing nests of mud and even (in one genus) resin. All are predatory, but the type of prey ranges from spiders to various dictyopterans or orthopteroids to caterpillars (of either Lepidoptera or other Hymenoptera); the vast majority practice mass provisioning, providing all the prey items prior to laying the egg. -- from Wikipedia


	I found these male and female wasps mating on a hot summer day. The male remained firmly aboard by clasping the female firmly behind the head with his mouthparts. I'm not sure if this is actually mating behavior or simply aggression, but the female seemed to go about her business nectaring at flowers, and the pair remained highly wary of my approach. This is sweaty, dirty work following these rapid flyers through the weeds.
	Thread-waisted Sphecid wasp in sleeping posture, Ammophila procera