Parasytic Wasp?

[eucera]

Crabronidae is the name of a family of wasps in the group Aculeata (The same broad group as social wasps, bees and ants). This is to distinguish it from the large group of "Parasitica", which includes Ichneumonidae, Chalcidae, Braconidae etc.

Solitary is a term which means there is no social structure. What you have observed is a wasp city. Lots of individuals, each going about their lives independently; no social cooperation, no queens and workers etc. They live close together because nesting substrates are usually rather rare

In UK we have a number of species of Ectemnius (10 species). They vary in size, patterning, range, choice of nest sites and a host of structural details that are visible under the microscope. The BWARS website certainly doesn't have pics of all of them (some are quite rare)

If you still have the specimen, I should be very happy to look at it and give you a species level identification. pm me for details!

[Nick Smith]

Thank you eucera, that is great information. Unfortunately the female Labyrinth Spider got the specimen but there was at least one more Ectemnius wasp living in the same location. I will try to observe it's behaviour later today. I could collect a specimen but if this is the only specimen left in my garden I would rather not. We are trying to create a natural garden (as much as possible) with a wide variety of habitats and flowers and plants that attract birds and insects. Rocks, pond, old logs etc, borders without pesticides, planted with a variety of flowering plants throughout the year. Our garden is not big by any stretch of the imagination but a few micro habitats here and there make a difference. We live in Suffolk on the edge of a town bordered quite closely by intense agricultural land. The only really natural habitat for any wildlife is about 3/4 of a mile away, where there is a small strip of natural woodland on the banks of the Lark River.

Regards, Nick.