Scapania paludicola and Matt's other finds

Matt Sutton has been busy in Pembrokeshire, looking for species that I missed whilst recording for The Mosses and Liverworts of Pembrokeshire.  He has made numerous new hectad records over the last couple of years, and found Ditrichum lineare new to the county in 2017.  Last year he made two additions - Bryum moravicum near Kilgetty and Scapania paludicola near Llangolman - as well as finding notably disjunct rarities such as Porella obtusata on the south coast near Saundersfoot and Cephaloziella turneri in a gully on the north coast near Strumble Head.  Although VC45 is probably the most intensely recorded county in Wales for bryophytes, diligent searching is bound to turn up new things.

Matt's Scapania paludicola is particularly welcome because it helps with a longstanding puzzle.  This species was thought to be very rare in Britain, but my CCW colleagues began finding it in pH-neutral mires across much of Wales and the Atlas suggests it is something of a Welsh speciality.  However, forms of Scapania irrigua mimic the leaf shape and arched keel of S. paludicola and I have long held a nagging doubt that the widespread Welsh plant might just be extreme S. irrigua.  This was not helped by the complete lack of gemmae on Welsh plants, unlike a couple I was sent from Scotland as Recorder for Hepatics.  Matt's find had dark gemmae, finally putting my mind at ease.  I am now confident that the Welsh mire Scapania really is S. paludicola.  Matt's plants were alongside typical neutral mire species: Sphagnum papillosum, Aulacomnium palustre and Straminergon stramineum.

Bog Earwort in Glamorgan

Two days ago I recorded small quantities of the Nationally Scarce Scapania paludicola at the same site I first noted it at in 2014 (top photo, one of several monitoring plots on Tair Carreg Moor), the land sitting in the shadow of the huge overburden mound on Merthyr Common. The vegetation in the area where it occurs is a mosaic of rather ordinary M24a and M6d, perhaps suggesting the species could be more widespread in the county than records currently indicate. Photographic sequences of the monitoring plot show the vegetation has become more rank in recent years due to reduced grazing, but despite this, low density bryos can still be found by carefully searching in the gaps between the tussocks of Molinia. Direct associates in this niche were all at very low abundance and included Calypogeia fissa, Hypnum jutlandicum, Scapania irrigua and Sphagnum denticulatum. The above photo shows the specimen collected in 2014, those below being from 2017, these perhaps better illustrating the strongly arched keel which gives the species its characteristic appearance.

Clare Mockridge has provided the bulk of Glamorgan records, with six entries from 1994 to 1998, a period of extensive Phase II NVC work in the county; though most records are from Llantrisant Common. The only other county record was provided by Peter (Sturgess) & Roy (Perry) at the Fochriw Reclamation Scheme Site in 2010. Wider searches will hopefully reveal more about this seemingly localised species.

Llyn Eiddwen

More news from distant West Wales.  Llyn Eiddwen is a NNR up in central Ceredigion, it has extensive mires on two sides which are owned by WTSWW and there are some quite choice bryophytes there.

I went in hope of refinding Sam's record of Pseudobryum cinclidioides but soon realised that it was unlikely to be above water since the lake was at least 1 or 2 feet higher than normal and much of the mire at the outflow end of the lake was submerged.  Still it was more than made up by finding numerous colonies of Scapania paludicola.


This distinctive species (did I just write that about a Scapania?) was growing on the tops of many of the Sphagnum hummocks scattered across the mire.  The keel is strongly arcuate but otherwise it is probably closest to S. irrigua although larger than many forms of that variable species.
Also of note were two patches of Cephalozia pleniceps, a rare species in Ceredigion, a hyper-abundance of Straminergon stramineum and a fine patch of Hamatocaulis vernicosus.  The mire is decidedly base enriched, at least in part, but I couldn't see any S. contortum or even Campylium stellatum although Sam had recorded the latter.  A nice patch of Riccardia palmata was a fairly good find for the county too but I was probably most pleased with some scraps of Cladopodiella francisci on a peaty bank at the edge of the mire as I had guessed it would be there if a scraping of liverworts from a vertical bank were examined but only a couple of shoots were present amongst a mat of Ceph bicusp and it would have needed a miracle to have spotted them in the field.

The site now has 144 species and there will undoubtedly be more to come.