Larvae from large aggregation at Clumber Park

[poschiavanus]

Just a quick post of a couple of pictures taken today.



We noted a couple of aggregations of these (presumed) larvae along Lime Tree Avenue today. They were very active swarming over each other.

They are insects (right number of segments) but appear to lack both true thoracic legs and any abdominal prolegs. They have a sclertoized head capsule, which looks fairly lepidopteran in appearance. Each segment has a ring of quite long spines, and a group of four spines at the tail end.

I've had a very quick flip through a couple of books, but I still don't know which order they are in. I'm currently assuming they are either moths, beetles or flies. As these aggregations were quite striking once sighted someone else may be able to put me on the right track.

Cheers,

Posch

[Dogghound]

They are Bibionidae larvae.

[Wild-Woman]

So maybe St Mark's Fly then DH? Interesting. Do they over-winter as larvae or pupae?

[Dogghound]

Possibly St Marks or something similar. You often find them in these large aggregations similar to the adults in many ways. They overwinter as larvae, or at least some species do as I regularly find them during winter in leaf litter, under decaying logs etc.

[poschiavanus]

Originally Posted by Dogghound

They are Bibionidae larvae.

Thanks DH.

I'd nearly got there last night (I'd narrowed it down to 2-3 families of Nematocera), when I got a tip-off from another WABber about information elsewhere on the net.

Since then I've read the HIBI Diptera Larva key and seen quite a few recent images of very similar insects and have found a key to the larvae of Bibionidae (albeit in Norwegian ). So I hope to give them a go in the next couple of days.

Hopefully quite a few other WABbers will recognise these next time too.