Identification notes
This is a moss with a restricted but quite well-defined kind of habitat. If you can find the habitat, you will often find the moss!
It does not have its own page in the Field Guide but is locally frequent in shaded, very humid situations in fast-flowing, base-poor watercourses. It likes to be splashed or inundated and is often to be found as low-growing, wiry patches close to the water on rocks below cascades and waterfalls. Associated species usually include Sciuro-hypnum plumosum, Hygrohypnella ochracea, Lejeunea lamacerina and more rarely, Rhynchostegium alopecuroides.
It may grow close to the similar-looking and very common H. heteropterum but is rarely found in the drier places on the bank preferred by that species. Both plants have small leaves, but if you look at them closely with a good x20 hand-lens, you should be able to see the stout nerve of H. wulfsbergii, at least on the larger stem leaves. In fact, the nerve makes the leaves look a little keeled, something not shown by H. heteropterum. If you are in any doubt, put a shoot under a dissecting microscope later on to check the nerve detail properly.
