Monday, 25 January 2016

Pylaisia polyantha

Highlight of today's lunchtime walk was a 30x15cm patch of Pylaisia polyantha on a horizontal Hazel on the edge of Redding's Inclosure.  This is another part of my target tetrad SO51J, with different habitats to those I have looked at elsewhere in the square.  As a result, additions included conifer plantation specialists such as Plagiothecium curvifolium (plentiful and fruiting), Hypnum jutlandicum, Pohlia wahlenbergii (on a track) and potential Sematophyllum substrumulosum and Bryoerythrophyllum ferruginascens (both to check).

NBN map of Pylaisia (yellow squares) with new site arrowed

Pylaisia is an eastern moss in Wales, with most colonies in Monmouthshire hedgerows where it tends to occupy a niche in the upper part of trimmed hedges, just below the level smashed by flailing each year.  I have found it once in Glamorgan and three times in the Llandeilo area of Carmarthenshire, and I suspect it should be present in George's neck of the woods.  It is most easily spotted in late winter because of its copious straight fruits, although it is easy to ignore as Homalothecium sericeum unless you have it in mind.

The photo is of a Monmouthshire hedgerow colony, not today's one (because I didn't have a camera with me).


  1. Another one to pin to the wanted board .... thanks for keeping us on our toes!

    Re Sematophyllum substrumulosum, i found some none-fruiting material that was probably just small Hypnum growing on decorticated log with Lophocolea heterophylla, but could not find any images that convinced me there was a way of separating the two in the absence of capsules. S.s. is said to have smaller auricles, but just wondered if there is a more reliable method or are capsules required?

  2. I wouldn't risk Sem substrum without capsules, but there might well be features when leaves of Hypnum and Sematophyllum are compared. My plant from today had a couple of nice big inflated alar cells each side of the leaf base. The leaf shape is slightly less consistently tapering than Hypnum too.

    PS I'm pretty sure George's mystery moss from the other day is Plagiothecium curvifolium

    PPS I had a moss with straight capsules on a conifer log that I eventually ignored and now wish I hadn't as I suspect it was more Pylaisia

    PPPS it's almost the season for Herzogiella...

  3. A few weeks ago I found what I thought might be Pylaisia on an ash near Cefn Onn, but it only had old headless capsules so I was going to go back in spring and see if it had any new ones...

    Thanks for Plagiothecium suggestion - I'm clearing sample backlog and that is next on my list.