Here are Charles and Barry next to a seeping limestone cliff that was covered with patches of Seligeria. Quite which were present remains to be seen, but there was definitely S. acutifolia with short setae and another with long setae. Elsewhere we found Cololejeunea calcarea, Platydictya jungermannioides, Amblystegium confervoides, Orthothecium intricatum, Brachythecium glareosum, Rhytidiadelphus subpinnatus and Anastrophyllum hellerianum. The sheer abundance of bryophytes was amazing, especially a bit further downstream where Loeskeobryum brevirostre was locally dominant on the woodland floor. All this in an area that had no previous records of notable bryophytes at all: Martha Newton's pioneering work was further downstream, and Graham and I had previously looked at the limestone ravine about 2 km upstream.
Having said that, the highlight of the day for me was a lichen! Sticta limbata on 2 Hazels, 2 Ash and 1 Hawthorn a few hundred metres upstream of Pwll-du, was new for the SAC and the BBNP.
[Here's the context shot I took of the Sticta limbata colony, with approximate positions of the main patches shown - I'll send you the unmarked photo to edit yourself in case you need to refine the areas - Barry]