Another thing was I knew it was going to be tricky before I even saw it - the person handing it over is an experienced coleopterist who knows his beetles, so if he can't ID it... Anyhow, being at the BENHS did mean that I had access to books and microscopes there and then, plus some other coleopterists to ask. So, starting at the start, it was about 5mm long, with blue-black elytra and head, an uptilted tip to the scutellum, orange-red pronotum, orange legs (apart from a small dark bit near the base) and dark (with an orange part near the base), fairly short antennae with triangular segments giving a somewhat serrated appearance. OK, that looks like, and keys out as, Smaragdina affinis - one of the leaf beetles (Chrysomelidae) and a rare one considered Endangered (RDB1) in Britain.
The mystery Smaragdina... |
There are other Smaragdina species in Europe - could one have found its way here, or been overlooked? Looking through the European species online and in books, I came to two possibilities - found not too far away in Europe, and broadly the right colour etc.- S. flavicollis and S. salicina. Looking at how to separate them, they are very similar - although varying in average length, the size ranges overlap and this specimen sits right in the middle of the overlap, so that's no guide. Also, both can have a hairless vertex to the head with a shallow round dent (which this does). So, off to the dissecting microscope.
Head on - a tricky little beast. |
Head showing round depression on the vertex between the eyes. |
Fortunately it's a male, so I could dissect out the aedeagus and compare it to those of the two possible species I'd come up with.
Aedeagus showing somewhat spatulate end, blunt 'pimple' at the tip, and other structures. |
So, do I have a species new to Britain? Well, it's not on the most recent British list and I don't know of any publications reporting it having been found here - still, finds like this need checking to make sure.
* UPDATE * My ID has been verified by an expert - it is S. salicina which is widespread in continental Europe, including France, so it is plausible that this is a genuine new species to Britain, either overlooked or recently arrived. Next step - try to work out whether it's established/breeding (and can go on the British list) or whether it is a one-off 'import'. More info when I know!
* UPDATE 2 * This has now been published as a paper:
Hubble, D. & Murray, D. (2011). First British record of Smaragdina salicina (Scopoli, 1763) (Chrysomelidae). The Coleopterist 20(1): 1-3.
I remember when I managed to get a damselfly record of a new 10km in the NE of England - I was pretty excited by that - but possibly new to the UK - that’s different altogether!
ReplyDeleteStewart M
I know - a first for me, even if I didn't collect it... currently feeling very excited as the ID is correct and it is salicina. Now to update the post and try to work out whether it's established in the UK or just a one-off 'import'...
ReplyDeleteI love it when an ID mystery proves to be something new and not just a mistake. Good on you for recognizing there was something odd going on here.
ReplyDeleteCheers :)
ReplyDelete