Entomological Housekeeping

Winter affords time for straightening the office, cleaning off the desk, and tidying up some stray specimens. Today's observation is a photograph of a Keyhole Wasp (genus Trypoxylon) that was reared from a cocoon found in a trap nest. Unfortunately I didn't notice the wasp when it emerged and was unable to get live photos and release the adult. So it will be pinned and labelled and added to the entomology collection.

Keyhole Wasps provision their nests with spiders, lots and lots of spiderlings are stuffed into each nest cell. While most male Hymenoptera take no part in provisioning, constructing, or tending the nests, male Keyhole Wasps help out the female, mostly by guarding the entrance to the nest while the female is away hunting. This protects the nest from parasitic wasps, such as cuckoo wasps, that would otherwise sneak into an unguarded nest.

The wasp in the photo emerged from the cocoon in the innermost nest cell. The wasps in the other two cocoons never emerged. The spiders photographed are from the third cell from the entrance. The cells with the spiders are failed cells; either an egg wasn't laid in these cells or the egg or the larva didn't survive to eat the spiders.

Posted on 10 de fevereiro de 2017, 03:55 AM by