Someone found this on our recent field trip to Henning Conservation Area. It was a good catch and a brave one considering its fierce appearance. On first glance it looks a little like a male velvet ant (the females are wingless). I posted it on Bugguide.net and within minutes I had a tentative ID, a Spider wasp - Psorthaspis sanguinea. We are now awaiting confirmation by a specialist.
There is essentially nothing on P. sanguinea on the web. It is a member of the Pompilidae family, a group characterized by their powerful sting which paralyzes a spider which is then dragged off to a nest. A single egg will be laid on the spider, which will remain alive while the wasp larva slowly consumes it until it pupates.Not only is its appearance enough to intimidate a bug collector, but its nickname "horse killer" should be a clue. We described the powerful sting of this family, which is ranked at the peak of the Schmidt pain scale, in a previous Tarantula Killer blog, Fortunately no Master Naturalists were hurt in filming this wasp.
This is one of a series on finds on the Master Naturalist training field trip. More pictures from the field trip are at Finds from the Field.