Hello Aeshna as far asI can see anything that is nocturnal and takes a bit of finding
has very sketchy records e.g.bats,glow worms records seem to end where tv begins!
Mind you, if you talk to older people (in the pub is a good place)and sow the seed quite a few will get back to you with reminiscenses,hear say,some even positive id of locations
The Mendip link started through a youngster and has progressed to an old chap naming
areas including a farm I pass daily!
If you like detective work you look for feeding grounds and habitat, ask around, people are very helpful(some make things up just to be helpful and beware of anyone who wants you on your own
)There are sites that will give botanical info or invertabrate info for counties from big surveys
I hope I have not chewed your ear off
good luck if you do attempt to find new colonies