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!

Upper Mellte - no surprises except a tame Robin

Another day in the Waterfalls - this time searching the Sgwd Clun-gwyn and Sgwd Isaf Clun-gwyn areas of the Mellte.  The morning was pretty slow, with a few colonies of Anastrophyllum hellerianum on Oaks about the sum total of interest.  We searched a lot of mist-zone Ash trees on the west bank below Sgwd Clun-gwyn, but despite an abundance of Lejeunea cavifolia they held none of its smaller relatives.  I wonder whether the river flows are perhaps not constant enough because of the reservoir upstream - something to investigate.  Eventually we crossed to the east bank and followed a gorge-walkers' path back down to the riverside, where Graham spotted a small patch of Drepanolejeunea on an Ash.  This was well downstream of the main-river waterfall, but was clearly associated with a cascading side stream.

Graham photographing the Drepanolejeunea, and the result he got

Progress downstream towards Sgwd Isaf Clun-gwyn was notable only for the paucity of notable bryophytes, although we did manage to locate some Colura in a gorse thicket.  At last we reached the Millstone Grit scree between Sgwd Isaf Clun-gwyn and Sgwd y Pannwr, and our luck changed.  Almost immediately we located Lepidozia cupressina, and not just a little bit: great mounds, with the largest covering over a square metre!  Graham found this population a few years ago, but only at its southern end, and today's visit allowed us to fully appreciate its extent: L. cupressina was frequent to abundant through a 100x40m area, with records from 17 different 8-figure GPS squares.

All of the bryophyte cover on the rocks and tree base in the left photo is L. cupressina!

I found a particularly photogenic patch of Lepidozia and tried to photograph it.  In flew a curious Robin, which landed on the Lepidozia and even ate a scrap of cheese from my finger.  This perky little character is clearly used to tourists, and followed us around for nearly half an hour.

The scree woodland also held a few patches of Jamesoniella autumnalis - the only time we saw it during the day - as well as several colonies of Plagiochila punctata.  Speculative collections of potential Hylocomium umbratum and Hypnum callichroum will be investigated fully tomorrow.

Large Jamesoniella autumnalis with red leaves, which had me hoping for Mylia, and potential Hylocomium umbratum (which is probably just H. brevirostre)

Well I wasn't expecting that!

Actually, to be honest I was secretly hoping that Santa might bring me some Daltonia splachnoides during one of my days in Coedydd Nedd a Mellte, but the first couple of hours today were so dull I was really shocked to see the pretty little fringed calyptrae poking out from a log covered in Scapania nemorea.  The location - well up the Mellte valleyside between Sgwd Isaf Clun-gwyn and Sgwd y Pannwr - was hardly classic for Hyperoceanic species, but I'm not complaining!  This is the 4th Welsh record of this UKBAP/Section 7 moss, following three on Salix in conifer plantations in Brechfa Forest, near Llyn Brianne and near Llanwonno in the Glamorgan valleys.  It was new for Breconshire, although the Llyn Brianne colony was only a stone's throw into Carmarthenshire.  The general theory is that this Hyperoceanic moss is a spore-vagrant from Ireland, following Colura but more ecologically demanding.  Its presence in Coedydd Nedd a Mellte SAC raises the unanswerable question of how many other Hyperoceanic rarities in the SAC are relatively recent arrivals and how many are relicts; it is notable, though, that Aphanolejeunea and Drepanolejeunea are only on riverside (mostly cascade-side) trees, so even if they are recent arrivals they have found their way to classic oceanic woodland micro-niches.

This was certainly the highlight of my day in the central Mellte, but some lovely patches of Drepanolejeunea hamatifolia on a classic riverside Ash tree below Sgwd y Pannwr, new for the Mellte, came a close second.

Otherwise, the west bank of the Mellte was good but predictable: Anastrophyllum hellerianum in a few places (only on 4 or 5 trees); equally scattered Jamesoniella autumnalis (on perhaps 15 logs & trees); Cephalozia catenulata, Lophozia incisa and Odontoschisma denudatum on logs in a side valley; one small colony of Plagiochila spinulosa; and a few tufts of Colura on riverside Hazel.  Abundant Zygodon rupestris with a few sporophytes was perhaps the biggest surprise, growing on trees in the mist zone of Sgwd Isaf Clun-gwyn.

Jamesoniella and Plagiochila in abundance

Graham and I searched another previously unknown section of Coedydd Nedd a Mellte SAC today, with oceanic liverworts our primary focus.  This went pretty well, overall, despite stygian darkness that made the search difficult.  Some sections of the Nedd are outstandingly rocky and bryophyte-rich!

We parked at Pont Melin-fach and started off on the west bank downstream of the carpark.  This area (SN90611025) holds one of the largest populations of Jamesoniella autumnalis either of us had ever seen, with some Oak trunks supporting 10s of extensive patches.

The entire bryophyte cover on this tree trunk is Jamesoniella!

After GPSing a good number of Jamesoniella trees and noting Tritomaria exsectiformis and Anastrophyllum hellerianum, we returned to the carpark and headed upstream, again on the west bank.  Jamesoniella and Anastrophyllum were each encountered a few times upstream of Pont Melin-fach, but never in abundance.  Instead, Plagiochila punctata was remarkably abundant, with Graham locating at least 4 colonies including one tree at SN90881076 with 50+ patches of this liverwort.  Although there are a few scattered colonies of P. punctata in the SAC, it is much rarer here than P. spinulosa.  Plagiochila bifaria was also present on one tree, and P. spinulosa was on a few rocky areas.

Remarkably, the Plagiochila punctata trees were in clifftop woodland; Graham is looking at the main tree.

Just before we reached the Plagiochila hotspot, I spotted 6 patches of Drepanolejeunea hamatifolia on a relatively young Ash by a cascading sidestream (SN90871068).  This is about 1.5km from the only previous record of Drepanolejeunea from the SAC, found a couple of months ago.

Further upstream, we found an area of rocky woodland where Bazzania trilobata was locally abundant, with 20+ patches in a 10x10m area (SN91001088).  Despite Coedydd Nedd a Mellte supporting the best example of Oceanic woodland in south Wales, there are very few colonies of Bazzania on the site, even though this species is found much further south and east in Wales than the SAC's rarer oceanic liverworts.

The final notable liverwort of the day is, like Bazzania, more interesting in a Coedydd Nedd a Mellte context than in a wider south Wales context: we found Colura calyptrifolia on at least 4 Hazel and Ash around SN91121105.  Despite this species being found in most of south Wales' conifer plantations, often in great abundance, this is only the 2nd or 3rd time is has been seen in the SAC.  It is, of course, a Hyperoceanic liverwort that used to be restricted in Wales to a few of the best oceanic woodland ravines, and its rarity in south Wales' ravines (even where Aphanolejeunea, Drepanolejeunea, Harpalejeunea and Plagiochila exigua are present) is intriguing.

Another section of this amazing site has now been explored, and more bryophyte hotspots found.  There's still the area upstream of Pont Rhyd-y-cnau to be done, plus the central Mellte.

Nedd-fechan - the Atlantic valley that just keeps giving!

I returned to the Nedd-fechan on 20th October, a month and a half after my previous visit when Aphanolejeunea and Kurzia trichoclados were discovered new for Breconshire.  This time I was joined by Graham Motley, as we were meeting John Douglass to discuss his lichen survey of the Coedydd Nedd a Mellte SAC.  We gathered at the confluence of the Nedd-fechan and Pyrddin, and started our day by searching the north (VC42) bank of the Pyrddin as far as Sgwd Gwladus.  Actually this wasn't quite the start of recording, as I had spotted Aphanolejeunea on an oak in the middle of the path (the 2nd record for VC41) and Graham had pointed out Plagiochila bifaria on the same tree.  This reminded us of our previous visit to the Pyrddin, when we found Aphanolejeunea new for Glamorgan and South Wales in the mist zone of Sgwd Gwladus.  Little did we know what was to follow...

Having met up with John, we proceeded upstream along the Pyrddin.  Pretty soon we reached the first, low waterfall, where Graham found a few patches of Aphanolejeunea on a Sycamore.  As we approached the big waterfall there was more and more of this Hyperoceanic liverwort - 10 to 20 patches on most of the Ash trunks overhanging the river - whilst a few more acid trunks held Anastrophyllum hellerianum.  The Pyrddin is clearly now ideal for Aphanolejeunea, despite this being the southernmost locality for the species in Britain.  There is no way of telling whether it has increased recently because there is no indication that anybody has searched those riverside trees in detail before.  The valley below Sgwd Gwladus is deep, and the algae, liverworts and lichens on the tree trunks looked pretty well hydrated.

Aphanolejeunea microscopica forming a bright yellow-green patch

alongside larger Lejeunea and Lophocolea

There was more to come.  After lunch, we headed up the Nedd-fechan towards Nant-y-llechau: on the opposite bank to where I found last month's Aphanolejeunea and Plagiochila exigua.  We descended just upstream of the first waterfall, finding an Oak with Plagiochila bifaria on the way down.  Again the riverside Ash trees were covered with algae, lichens and Lejeunea, and pretty soon I spotted the species we had been discussing all day: Drepanolejeunea hamatifolia new for Breconshire.  There was a good lot of it - at least 20 small patches with perianths and male bracts, on the twin trunks of a young ash on the riverbank.  While I was admiring this colony, Graham wandered downstream a few yards and found Aphanolejeunea and Plagiochila exigua on another slender Ash.  Along with last month's finds, this is clearly a major hotspot for oceanic bryophytes.

Microscope pic of Drepanolejeunea (sorry, I forgot my camera in the field), and the adjacent 'lejeunea trees

Coedydd Nedd a Mellte SAC keeps producing new oceanic liverworts 15 years after Graham and I first visited, and I am sure there is more to find because several sections have never been searched.  It really is an astonishingly special place.  Our next trip will be to the central Mellte, upstream from the area where several bryologists searched in the spring; and then there's the Hepste near Sgwd yr Eira, last visited by us in 2001; and the Sgwd Clun-gwyn area, which has been visited several times but never with mist zones in mind; and Sgwd y Pannwr, and Pont Rhyd-y-cnau, and doubtless other places.

More Marchesinia

Marchesinia mackaii has appeared on this Blog several times recently, but this colony is rather different.

Our South Wales colonies are on limestone, whereas this one covers many square metres of igneous rock at Coed Tremadog.  I visited this outstanding lichen site, near Porthmadog, yesterday morning en route to a site visit in snowy Eryri.  Other highlights included Plagiochila britannica, P. bifaria and some potential Radula lindenbergiana.  Chris Forster Brown has found Leptodon smithii and Anomodon viticulosus there, and I'm sure that many more notable species would be found if several days were spent exploring, as the rock is very base-rich in places. 

There's a distinctly lowland, south-eastern feel to the flora, with species such as Eurhynchium pumilum and Neckera complanata more frequent than in most of Eryri.  The wonderful pink fungus Phlebia radiata appears from the NBN Gateway map to be similarly south-eastern in Britain, and no other Meirionydd records are shown.

Recording in a ravine later in the morning produced new populations of Drepanolejeunea and Harpalejeunea on a slender Ash in a small waterfall mist zone, both within a SSSI with a diverse oceanic flora but no previous records of these hyperoceanic liverworts.  It is great that even well-worked Eryri can produce surprises.

Recording in Eryri is enhanced by the wonderful landscape: snow-covered Moel Hebog was especially prominent in the background yesterday.