Homage in the Hepste

It's nearly 18 years since Graham and I visited Sgwd yr Eira to pay homage to the southernmost British population of Sphenolobopsis pearsonii - found by Martha Newton in 1994 and 'twitched' by us in 1999.  We were glad to see that this Nationally Scarce liverwort is still present on one rockface (we assume it's the same one where Martha found it, though we haven't yet checked), but were worried to see that most of the patch looks moribund.

On our way to the Sphenolobopsis we searched the ravine downstream - where Plagiochila bifaria was present in a classic mist-zone location - and some south-facing cliffs where putative Ctenidium molluscum var robustum (or perhaps var condensatum) grew close to var molluscum and looked convincingly different (if un-nameable).  Nearby there was some Dicranum montanum on a log.

Then we reached Sgwd yr Eira, with its classic walk-behind waterfall and extensive mist zone.  Most Ash trunks were plastered with algae - too humid for anything else perhaps - but eventually we found some Plagiochila exigua at the base of an Ash.  Unlike the small Lejeuneaceae this species lacks propagules, so it's a sure-fire indicator of long-term Atlantic bryophyte richness in the valley.

The first stretch upstream of Sgwd yr Eira was a bit dull, but frequent Anastrophyllum hellerianum on logs and a few patches of Filmy Ferns kept us going until we reached a set of low cascades.  At long last there was some Aphanolejeunea - 30+ patches on a Willow and 1 on a massive boulder - the first record for the Hepste-Mellte catchment.  Careful scrutiny revealed a single shoot of Drepanolejeunea growing alongside one Aphanolejeunea patch, but we couldn't find any more.

Happy with our lot we continued upstream in the fading light, where a yapa (Bolivian word for an added bonus) came in the form of Hygrobiella laxifolia on a riverside rock shelf.  The godfather of south Wales bryology HH Knight found this species in "Hepste Glen" in the early 20th century, but nobody had seen it since.  This was a fitting end to an outstanding final day of our Coedydd Nedd a Mellte survey!