Like it or not, there are people around who like to have a few ‘trophy collections’. This even includes lichen folks. I have been told of an extremely rare lichen having one of its 3 known populations nearly wiped out by a collector.
Please do not post precise locations of at-risk species here, as this discussion board is public and searchable from google! As the administrator of the site, the one form of censorship I plan to practice will be removal of precise location information for at-risk species when I notice it in posts or if others notify me of them!
If you want to communicate a location to another user of these discussions, you can probably find their email address in the membership list, or even get to their profile by clicking their name at the upper-left of the message. Or, you can leave a post asking them to get back to you. Or, since the lichen community is relatively small, you can probably find their contact information some other way pretty easily.