Unknown Beetle larvae/Pupa

[Dogghound]

Found this larva whilst looking in a nest box today. The larva was around 2-3mm in size. I dont think it has any direct association with birds or their nests as the box has been empty quite a while, I think it was using the nest box to hibernate, there were around 20 individuals in the nest box all the same species as well as several pupa of what im certain are the same species.

The pupa Slightly larger than the larvae as expected. by about 1mm.


Im 100% sure their beetles but which species any ideas? P.S Its not a wooly bear, incase anyone is thinking along those lines.

Thankyou. Im Grateful for any info.

[Paul mabbott]

Sorry, not much of an idea. They are probably close to Anthrenus? Was the nest box totally devoid of contents. A bird's nest will provide nutrition for a population of carpet beetles for four or five years so a few feathers or exfoliated skins cells would provide significant nutrition.
Only way to know is to hatch it out - keep us informed!

[Dogghound]

Originally Posted by Paul mabbott

Sorry, not much of an idea. They are probably close to Anthrenus? Was the nest box totally devoid of contents. A bird's nest will provide nutrition for a population of carpet beetles for four or five years so a few feathers or exfoliated skins cells would provide significant nutrition.
Only way to know is to hatch it out - keep us informed!

Will do Paul, ill collect some pupa before any birds make home there. The nest box is practically empty apart from the odd hair (mammal hair that is) which is a little odd.

Cheers for the pointer. Although the larva look different from Anthrenus, less hairy and, not banded. Although i have found several adults last year in the garden. These are bigger than the pupa. .