Aphanolejeunea in Brechfa Forest

On Friday I spent a few hours revisiting the lichen hotspot in the valley of the Afon Marlais, a few miles upstream of Brechfa, to record some previously unexplored sections of the site.  The lichens were excellent, with 3 spp of Sticta (including really large S. fuliginosa sl), some beautiful patches of Pannaria conoplea (only 4 sites in S Wales), and a few new lichens for the site such as Thelotrema lepadinum and Megalaria pulverea.  I didn't look at bryophytes too much, but couldn't help noticing that many of the riverside Ash trees were plastered with Aphanolejeunea microscopica as well as Colura.


The only previous Carmarthenshire record of Aphanolejeunea came from the Mynydd Mallaen area nearly 15 years ago, and the abundance of Aphanolejeunea along the Afon Marlais was reminiscent of its abundance in the Waterfalls area of the Nedd/Mellte valleys of VC42.  I couldn't find any Drepanolejeunea on Friday, but did see it by a waterfall in a tributary of the Afon Marlais a few years ago.  Earlier last week I revisited Cwm Marydd, where Tritomaria exsecta is still doing well.

Southernmost Aphanolejeunea

Graham and I have nearly finished our report on the oceanic bryophytes of Coedydd Nedd a Mellte SAC, with our own photos plus a few by other South Wales Bryologists.  The only gap was the Aphanolejeunea colony in the middle of the footpath to Sgwd Gwladus - in Glamorgan and the southernmost patches of this species in Britain.  Bea and Johnny were keen on a visit to the waterfall today, and I managed to surreptitiously grab a photo of the tree as well.  Double success :-)

The Aphanolejeunea tree - admire but do not collect!!

The only other bryophyte I noticed was a relatively large Fossombronia on one of the dry promontories in the river (again in Glamorgan); sadly there were no sporophytes and I didn't want to check its rhizoids because there were only two thalli.  Something to revisit.
 

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.

Wonderful Waterfalls Country

The Nedd and Mellte valleys in southern Breconshire have long been known as a bryological hotspot: they are SAC for their Old Sessile Oakwood and Tilio-Acerion habitats and hold many miles of deeply-incised valley woodland.  Over the last 20 years, the valleys have produced many bryological gems, including Aphanolejeunea microscopica new for Glamorgan, Plagiochila exigua new for Breconshire, and the largest known British population of Rhytidiadelphus subpinnatus.  Despite many visits by different people, included a funded bryophyte survey lasting several weeks, there remain several areas with no records of notable species at all: is this because they are dull or just inaccessible?  The visit Graham and I made to an unknown section of the Mellte earlier in the year suggested that hotspots remain undiscovered; a day in the Nedd valley below Glan-yr-afon (SN9009) redoubles that feeling!

This area really is outstandingly rich in oceanic bryophytes, especially in a south Wales context.  Photos of highlights follow:

Aphanolejeunea microscopica - on one slender Ash downstream of the downstream-most major waterfall on this section of the river.  The second record for the SAC and new for Breconshire, following a colony on the Pyrddin in Glamorgan about 1.5 km to the west.

Plagiochila exigua - a large patch on a slender Oak overhanging the river, just downstream of the 2nd major waterfall as I worked my way upstream.  Very clearly associated with mist from the waterfall.  The second record for Breconshire and the SAC, following a colony found by Graham in 2011 on base-rich rocks about 3km to the north.

Plagiochila bifaria - sharing the Oak with P. exigua, where it formed a patch nearly 1m long.  The third record for Breconshire and the SAC, following colonies Graham and I spotted by the Nedd 2km to the north and on dry cliffs above the Mellte earlier this year.

Anastrophyllum hellerianum - on at least 7 Oaks above the 2nd waterfall and on 1 Oak above the 3rd major waterfall as I went upstream.  I looked at many, many other Oaks in the valley and the clustering of Anastrophyllum, Jamesoniella autumnalis and Blepharostoma trichophyllum around these 2 waterfalls was really obvious.

Rhytidiadelphus subpinnatus - 2 colonies seen: 1 on a boundary bank near Glan-yr-afon looked rather scrappy and intermediate, but this 1x1m patch on an Ash bole just above the river was absolutely classic!

Hymenophyllum tunbrigense - an honorary bryophyte that occurs in remarkable abundance in this part of the Nedd valley.  I took GPS readings for at least 20 different patches, most of which were >1x1m in extent.  Plagiochila spinulosa was alongside most of them.

A mystery liverwort - this is probably Kurzia trichoclados on humus on a Hymenophyllum crag, but it was very glistening and looks 'wrong'.  It is possible that this could be Telaranea europaea... annoyingly my compound microscope has bust, so I can't be sure.  If it is 'just' the Kurzia then it is new for Breconshire and the SAC, but if my dreams came through it would be the 3rd British record of the Telaranea!

There are still several completely unknown sections of the SAC and I have no doubt that more rare bryophytes await discovery.  Graham and I will be writing a report covering the bryophyte interest of the SAC this winter, which will help identify the gaps and should prompt a couple more expeditions.