Your intuition is right - termites! No not in the house! They are highly destructive. I would put that thing outside and get some termite control product from the Home store.

Doesn't look like a woodworm beetle, but it does kind of resemble reticulitermes lucifugus grassei, commonly known as mediterranean termite. Colonies of those are as close as coastal France, but not usually seen here.

A small reticulitermes termite colony was found in North Devon in 1998,though it's not clear which particular variety it was - they are not native to the UK and have not previously been an issue in this country, see article in the link

http://news.bbc.co.uk/1/hi/uk/77797.stm

I don't know which part of the UK you're in; if its a cold region (in the north, for instance) its less likely to be a termite, but you probably should contact your local council about them - someone somewhere may be tracking the progress of these insects in this country. I hope its not a termite, but either way, I'd be removing that christmas tree back outdoors asap...

Hopefully Seaburngirl will see this question - she is the most likely to know precisely what this insect is.

welcome to GoY :o)

Its not wood worm beetle [had those!] nor is it Hylotrupes as both have wing cases as adults and look like maggots [legless] as larvae.
There are no native termites in the uk and again they tend to have very soft, pale bodies.

These appear to have fine bristles on their abdomen and I cant see what their eyes and mouthparts are like.

They remind me more of wingless thrips to be honest. The bristles and their antennae are very distinctive. But I cant find a good match.
Where in the uk are you and where did you get your tree from?

You could email the British entomological society with an image or the natural history museum. I have sent the NHM specimens to id in the past. they are usually very good.

Thank you all for your very quick replies :) I've put it outside now just in case. I bought it in B&Q in Scotland it's a Nordmann Fir (south Black Sea - could be some form of reticulitermes) and thanks that's a good tip about the council/ NHM. I guess a picture of eyes/mouth are best ways to ID?

I noticed today that they can jump too and there were even tinier yellowish/translucent ones (not sure if that makes any difference). They're gone now anyway so unless I see dust in the wood I'm not too concerned.

Happy Christmas to you all!

I discounted these Reticulitermes as according to my guide the European ones are as far north as Bordeaux and Northern Italy.
but do you mean it was sourced from the south Black sea?

That Christmas tree could have come from anywhere. The whole lot was probably infected.

If it was originally from the southern end of the Black Sea, that makes it much more likely its Reticulitermes... but will they survive and thrive outdoors in Scotland? Hopefully not...

I am of the opinion; as Seaburngirl suggests that they look very much like a thrip. Trying to troll through the Internet would end up with you wasting hours. I would; as suggested take the tree outside and I would put a heavy hose spray on it before bringing it back inside.

I would never bring the tree back inside again. Just hang up some mistletoe and sing Christmas Carols.

And send off the specimens to the relevant place. I would burn the tree pronto just in case!

They look like tiny versions of longhorn beetles - but without wing cases. (I can't find a good match.)