Name that pupa! (1 Viewer)

[Mis]

I found this pupa on a thistle leaf today (SE edge of London). It is flatter than a ladybird pupa and about 7mm long. I say pupa rather than exuvia because it appeared to still have contents but may have been a failure and in the process of drying out. The two dark spots give it the appearance of a bizarre mask!
Can anyone identify it for me please?

 

[Mis]

I think I've found it. It could be Cassida rubiginosa, the thistle tortoise beetle. I'll have to search the area for adults but it seems they aren't easy to spot.

 

[Brian Stone]

Seems little doubt. A new one on me. Well done for tracking down the ID.
http://www.bioimages.org.uk/HTML/P4/P49845.php

 

[paul mabbott]

Yes and no! Most likely a Cassida - they (and some relatives) have pupae like this - commonly covered in frass for extra defence). However there are several species in UK (more globally) and C. rubiginosa is not the only common one in London.

http://culex.biol.uni.wroc.pl/cassidae/katalog internetowy/index.htm - for comprehensive information.