Does Anomalon parasitize oak leaf rolling weevils?

In the part of Florida I'm visiting, oaks are covered with the nidi of oak leaf rolling weevils (Homoeolabus analis). They are easy to miss if you're not looking for them but once you see one you can see the hundreds or thousands in almost every tree. And in some places they fall to the ground in such numbers that they crunch as you walk on them. It's no surprise to anyone that they get parasitized, of course, and I've been reading up on them. There's enough going on inside that a book could be written. If you teach biology, they would be super fun to use for an ecology laboratory exercise, a la goldenrod galls.

Anyway, I've noticed that a small, absolutely adorable ichneumonid, Anomalon sp., is surprisingly common on oak trees in the area. I haven't exhaustively scanned for the wasp at other trees, but my sense is that something is attracting them to oaks, especially live oaks. Males are common and they seem to be searching leaves carefully, though I'm not sure for what. I've only found one female so far and she was doing the same, at one point pausing and eating something off of a damaged leaf part. So they could just be foraging for something to eat. But I'm suspicious, and am wondering whether the beetle is a host for the wasp. It's not in the literature as far as I know so I thought I'd make a journal post that might be of interest to somebody who actually knows stuff about this wasp or beetle. If that's you and you've stumbled on this post, I'd love to know more.

Posted on June 27, 2018 03:07 PM by colinpurrington