Coed Rheidol

A couple of jobs up north gave me an excuse to spend Sunday afternoon up the Rheidol valley to the north of Devil's Bridge. I wasn't expecting to add anything to this well-recorded site, but Bosanquet's rule held true - the best sites always do have more.

Drepanolejeunea hamatifolia

The single patch of Drepanolejeunea on a riverside rockface just downstream of Temple Mine doesn't appear in the census catalogue for Ceredigion, but the late Chris Forster-Brown reported a tiny patch from an oak further south during his survey of the NNR in 2020. 

The mine itself had Grimmia donniana, and a Pohlia with brown bulbils which had me hoping for andalusica - unfortunately just annontina under the microscope. I failed to notice any of the Gymnomitrion obtusum previously recorded here. A little further upstream, I found some Hylocomiastrum umbratum, Dicranum scottianum with ripe capsules and Lepidozia cupressina; I also re-recorded a patch of Plagiochila heterophylla found by Tom.

Plagiochila heterophylla

A few yards away, a leaning oak tree held a couple of good liverwort patches which included Scapania umbrosa and some potential Lophozia longidens, although I'm struggling to find the red gemmae to clinch the latter (finally! see photo below).  My recent find in south Pembs is the only other modern Welsh record, and it hadn't been recorded in Ceredigion before.

Lophozia longidens and habitat

Lastly, some dry crags on the valley side had a small Cynodontium which needs further work. Difficult without capsules, but it's unistratose and smooth-celled - possibly tenellum. 

Bryum cf. gemmiparum again

 

A spring tide gave me a chance to revisit the cove near Tenby with putative Bryum gemmiparum. Although there are a few cushions on irrigated shale rockfaces, I didn't manage to find any bulbils so it still won't be confirmed. These photos do look convincingly similar to those of the real thing though.

 Treffgarne and Rosebush

There's a flooded quarry by the main road just north of Treffgarne which I'd kayaked on once, but never mossed in. Lots of Lophozia excisa fruiting happily on the track on the way in. A climb up to the millstone grit crag at the back of the quarry initially seemed disappointing, but I collected a specimen of a small, slender pleurocarp from the base of it which appears to be a good candidate for Homomallium incurvatum. I may be guilty of showing my workings again.....(I was, as Tom Blockeel helpfully confirmed - although macroscopically right for Homomallium, the alar cells are too irregular and incrassate - the illustrations in Smith's flora are apparently very misleading).

A somewhat similar but slightly larger pleurocarp from the wooded area below has deciduous branches and appears to be Platygyrium repens which would be a county first. 

On to Treffgarne Tors, where I located Bazzania trilobata and Hymenophyllum tunbrigense, but not the Lepidozia cupressina. Various patches of Lepidozia reptans, but if its uncommon relative is still there, it's not doing very well. I carried on to Puncheston, where the common at Waun Fawr is definitely in trouble - rank Molinia over the once lovely flushes. I went on to Rosebush Quarry instead, where the Cynodontium tenellum appeared to be flourishing, and cushions of Sphagnum russowii were looking good.

Sphagnum russowii mixed with fimbriatum

Cynodontium tenellum

The last moss of the day, from lime mortar on an old quarry building, proved to be the most interesting. The long mucro on this Aloina seems to make it Aloina obliquifolia, a European species which isn't on the British list. Such mucronate specimens are assigned to Aloina rigida var. mucronata in the UK, despite being distinguished as A. obliquifolia in the European checklist. It certainly looks different to and much larger than the blunt-leaved rigida that I'm familiar with from Pendine and the south Pembs limestone. There was only one small patch of it, but it had ripe capsules.

Aloina obliquifolia

By Hook or by Brook

Sanionia uncinata habitat, Eastern Cleddau

Waders on for some otter survey work for NRW around Gweunydd Blaencleddau SAC this week. First a chance to finally find some Sanionia uncinata in the county, which had eluded me thus far. Some good patches on grey willows sprawling across the channel. 

Sanionia uncinata

I'll confess to not being particularly experienced with hook mosses, so I went up to the flushes on Dolau isaf to refresh my memory. The Scorpidium cossonii was easy enough, but there was a Palustriella at the top end below the main calcareous spring that I had to collect. 

Under the microscope, the shape of the stem leaves suggested that it wasn't falcata - the regular species of base-rich springs on Preseli, but commutata. I tried to turn it into decipiens, thinking that I'd found papillae as well as prorate cell ends:

Although they looked tall and conical to me, Sharon concluded that these are still just prorate cells so, unsurprisingly, my speculative attempt at a new species for Wales were quashed.  However, with Palustriella commutata dominant and Cratoneuron filicinum frequent, this represents a small area of an Annex 1 habitat previously overlooked on the site - Petrifying Springs with Tufa formation (Cratoneurion). In common with many Welsh examples it lacks the tufaceous element. It narrowly escaped some channel excavation work done in the name of southern damsefly conservation, which stop just 3m short of the patch. 

I thought that the Pohlia around three of these spring heads might bet wahlenbergii var. glacialis, quite tall and with some mid-leaf cells around 30um wide. Sharon corrected me again - the leaf shape is a better fit for var. wahlenbergii and it's just a tall version of that.

Pohlia wahlenbergii and habitat

Back on the river again, I checked a few willows and rocks for Harpalejeunea molleri which grows in the next valley over, but no joy. Lots of otter spraints to record on the rocks though, and couches amongst the sedge tussocks. Mink evidence too. Willow tits in four places - this is a proper hot-spot for them.