Ruby-tailed Wasp

Just outside the patio doors leading to the back garden we have a small Bay tree in a pot. It’s being doing well there in its south east aspect, and receives full sun for half the day. Although the flowers are inconspicuous and only appear earlier in the year at this time in late summer it still attracts its fair share of visitors. Wasps and overflies seem to like it, searching for something that I can’t see. But the past two weeks I’ve noticed another visitor I’ve only seen occasionally, and then not in the garden. This is a solitary wasp and despite it’s diminutive size, only about 10mm, it ia a beauty. Being small and pretty active it was a challenge to get a decent photo, but I eventually managed to get a couple I’m happy with.

Now I’m going to disappoint you here and tell you straight away that I can’t give you an exact name other than it is a Ruby-Tailed Wasp, a member of the Chrysis genus. Why am I being difficult? The reason is easy, and one I come up against often when trying to identify mini beasts. There are over 15 species within the genus and they all look very similar. So much of a look alike are they that 3 things are needed: an expert, a microscope and dissection skills. I am not an expert, I don’t have a microscope, nor do I have the inclination to spend time to dissect tiny insects. That said, it might be Chrysis Ignita, but........

Ruby-tailed Wasps are solitary and are parasitic on other wasps and solitary bees. The eggs are laid in the feels of the hosts, hatching out to devour the host larva and emerge the next year to start the cycle over again. Entering a wasps nest to lay it’s egg can be a dangerous activity, and in order to protect itself from the wasp stinging and killing it, Ruby-tailed Wasps have evolved  a highly slecrotized exoskeleton making in impenetrable to the host wasp. It also has another defensive action when discovered creeping around the host’s nest by rolling into a ball, making it even more difficult to attack.
Between April and September you can find Ruby-Tailed Wasps running over walls, banks and tree trunks searching for the host nests. The wasps have two basic strategies in parasitizing hosts. The first involves cleptoparasitism where the newly emerged larva of the Ruby-tailed Wasp eats the host egg or the young host larva and then eats the food resources left by the host in the nest. The second strategy first eats the food store and then feeds on the host larva. The shining apparatus has evolved into a multi tool that allows the Ruby-tailed wasp to saw or penetrate through the cell wall of the host wasp, then the ovipositor is used to lay the egg into the host large a=or near it, depending upon the parasitic strategy used. It’s a jungle out there!