Thursday, 1 January 2015

Freezing Fun

Icy Thamnobryum by a stream.
The freezing nights between Christmas and New Year weren't exactly ideal for bryology, but at least we didn't get moss-burying carpets of snow!  I spent a day recording in three tetrads south of Trelech in western Carms - SN22T, SN22X and SN22Y - getting 80+ in the first two and ca70 in the third.  This area is typical of the 'dairy zone', but the valleys have footpaths so give up some of their diversity.

Epiphyte highlights were abundant Frullania tamarisci and Neckera pumila, along with Lejeunea cavifolia.
Lane banks supported Marsupella emarginata in two places and one colony of Bryum sauteri, as well as Cirriphyllum piliferum and Rhytidiadelphus triquetrus.
Didymodon nicholsonii grew in abundance on tarmac and there were a few patches of Syntrichia latifolia in one place.
A wooded flush with abundant Golden Saxifrage was locus classicus for large Aneura cf euromaxima/pellioides.
Fissidens celticus, F. curnovii, Heterocladium heteropterum and Hookeria lucens were present near streams, and one river bank held Epipterygium tozeri

The dairy plateaux above were dull as ditch water, and even the valleys were hardly riveting, but another three tetrads have been ticked off leaving just 92 unvisited (by me) in Carms.

Aneura cf euromaxima in a wooded flush. 
A poor photo but showing the typical large size and undulate margins.


  1. A good bit of square bashing there Sam. I can't see any reference euromaxima in Paten and wonder if there is an accessible reference to the id features?

  2. Your best references to the Aneura situation are my Pembs Flora and the Atlas. It's all a bit of a muddle: basically research in Edinburgh has shown that there are 7 genetically different Aneura in Britain, one of which is Aneura (Cryptothallus) mirabilis. Some of the reminder are small things that tightly adhere to the substrate - think dune slack or base-rich slag - that's the typical Aneura pinguis and perhaps another thing. Some are very much larger, looking very much like a Pellia, and have various names in various places. They tend to grow in stony woodland flushes or wet woodland, often over fallen twigs in permanently wet places. One of these has been dubbed A euromaxima by Edinburgh, but there's another genetically distinct thing that looks macroscopically identical: it may differ in oil body or sporophyte characters but more work is needed. The third group is some medium-sized, rather loosely adhering Aneura, typical of flushed upland crags etc (soggy ledges with Drepanocladus and algal gunk); one of these has been dubbed A britannica, but again more work is needed. It is quite possible that the 6 non-white Aneura will have morphological characters worked out at some stage, but it is proving difficult to match the morphology to the DNA at the moment.

    A final twist is the reporting of the American species Aneura maxima new to Europe from the Ardennes in the 1990s. There were suggestions that this was introduced in the 2nd World War (!). Subsequently there have been publications of A. maxima new to a series of European countries, notably not including Britain. We have the same thing here, but Edinburgh have shown it is distinct from true A maxima (and also the SE Asian A pellioides, which was another suggested ID for the European stuff) so rightly do not want to add to the catalogue of errors by publishing A maxima as a British species.

    My square-bashing in Carms with Graham really started the whole ball rolling: I found these big thallose jobs that quite clearly weren't Pellia, sent some to the Belgian chap who had reported A maxima new to Europe and had confirmation of the ID from him, but then sent it to Jean Paton who said it was too big for A maxima (!). Anyway, it is pretty commonplace in Wales and doubtless throughout much of NW Britain, we just don't have a good name for it yet! I record it separately from small A. pinguis as "Aneura sp.".


  3. Thanks for that detail - fascinating stuff and good to know we still have a lot to learn about these plants