As some may remember, I in May requested help in identifying a
semiaquatic moss I'd found locally, and which grew well in my aquarium
(still does, btw).

Anyway, the moss has now been tentatively ID'd as Leptodictyum
riparium, an apparently common european moss inhabiting shallow waters
(e.g. brooks, lakeshores, by waterfalls...).

Pictures & a little info can be found he
http://mikes-machine.mine.nu/Mysterymoss.htm