Yellow Spectacled Ichneumon

This picture was taken in the conservatory on the 3rd December and shows that with the continuing mild weather, there are still insects to be found.

On first inspection of this creature, I mistakenly thought that this was some sort of sawfly due to the saw-like ovipositor (the elongate structure located at the tip of a female insect's abdomen).

However, sawflies do not have a distinct waist between the thorax and abdomen. In my picture you can just make out a narrowing of the waist, which makes this an Ichneumon fly. What makes this group of insects interesting is that they are parasites. The ovipositor is used to lay the egg or eggs inside the body of another victim. The host is selected by scent and, although many ichneumons are active at night, they can often be seen searching for hosts in the daytime. They fly low over the vegetation or scuttle about on the plants with their antennae waving vigorously to pick up the scent. Most species attack the caterpillars of butterflies and moths.

It is very difficult to get a positive identification of this group of insects, as there does not appear to be any identification guides available, and the best that I can come up with is Tromatobia oculatoria. The main identification feature for me is the yellow band that surrounds the eyes, and therefore I'm going to give this my own name of the Yellow Spectacled Ichneumon. If I'm correct with the identification, then this little chappie is actually a parasitoid of particular spiders.