Unidentified Insect mid moult....

[ollyk]

Hi at a local NR today looking round, as always peering into the water when I noticed this insect lying at the bottom..



Watched for a while and after a few minutes there was a wriggle, at this point it became obvious the creature was part way through shedding it's skin, and in my opinion, struggling...

I was too curious to overlook this so I carefully removed from the water and what I found has got me rather puzzled tbh!







Size was quite large. To give you an idea, my finger 'segment' in pic unknown2 is 1 1/4", so about 1 1/2" in all. Legs and antenna were all free to move (but part of section not yet released) so I thought this was not likely to be a pupa but some sort of instar or final moult from a nymph?, to me this rules out a moth or similar that might have accidentally fallen in... The antenna however suggests this is indeed a terrestrial critter that could have fallen in

One more thing - are they gills I can see on the abdomen or part of the shed process?

I do not know where to start so help would be appreciated!

[ollyk]

Could this be a caddis larvae in final stages? Abdomen is very large but maybe it had been puffed up to split the old skin...?

Thoughts appreciated.

[AndyC]

It's a mess!
Maybe caddis but it looks more like an alder fly to me.


Andy

[ollyk]

Andy thanks for that. Hadn't thought about alder fly..
I agree it doesn't look like things were going well for this poor creature. I know from owning sickies this process is normally fairly quick to minimise risk of predation.