Rare fungus on Weissia multicapsularis

There aren't many rarer British mosses than Weissia multicapsularis, as it has fewer than 5 known colonies in the World!  Its first Welsh record came from Dingestow in 1981 (when I was too young to appreciate mosses) and it was a thorn in my side, with 15 failed attempts at relocation, until I found my own colony about 1km from the original site in 2008.  I revisited the colony this afternoon and tall, brownish, short-leaved Weissia are frequent over the same area as I marked in 2008, although I completely failed to find any sporophytes to confirm the ID.  The site seems utterly mundane - a steep bank in improved pasture - but also supports Acaulon muticum, Weissia squarrosa and lots of a small Fissidens that looks likely to be F. crispus.  I suspect it has never been overly fertilised because it is too steep, and a combination of a SW-aspect, grazing and slumping prevent takeover by vascular plants.

Anyway, one patch of Weissia had a little orange fungus growing at its base.  I figured that a fungus growing on Weissia multicapsularis could be pretty rare, so I carefully collected the fungus and 3 stems of the moss for identification.  It looked rather ill-defined compared with most Octospora that I have seen, perhaps because of the membranaceous margin (something mentioned on the excellent Bryoparasitic Pezizales site http://www.octospora.de/Ltuberculatella.htm).  Under the microscope it had remarkably lobed asci containing 8 strongly warted spores.  A check on the Pezizales website suggested the only fungus recorded so far from Weissia species is Lamprospora tuberculatella, which has spores that are identical to my specimen.  From what I can see on-line, there are no previous British records, so a very rare moss may support an even rarer (in British terms) fungus.