Thursday, 2 April 2015

Herzog's Pocket-moss

A belated post from 28th March of Fissidens crispus (=limbatus) which I collected from soil encrusted rocks below the quarry face at Wern-halog, just east of Llanrhidian at SS50809349, found growing directly alongside F. viridulus and Oxyrrhynchium pumilum. The quarry exposure is part of the Millstone Grit Group (which I've always understood to be principally acid), but the plant assemblage shows there is some basic influence. You can get an indication of the protuberant leaf cells in the image below, but this was much clearer in binocular vision; this along with the small cell size making the id straight forward using Smith.


  1. Hi Barry, you are correct with your assumption.

    I am sure you are aware of this but if not:

    The Geology of Britain Viewer (link at base) is a free open access way to view geology and if you click on an area (and then in the pop up 'further details') it will take you to a description of the geology. Embarrassingly it has no description of the Llanelen Sandstone member (poss what is in your quarry) but it will work for most other areas.

    Perhaps the base richness is locally from the till (if there is any there ?!).

    The maps have recently been upgraded to 1:50,000 scale so you get an OK view.

    Not a bad resource for £0 !


  2. Well done Barry - I've only seen F limbatus/crispus 5 or 6 times full-stop and there are fewer than 20 Welsh records (from memory). The long perichaetial leaves seem to be a good pointer, but it's very easy to overlook.

  3. Having the geological maps to hand is incredibly useful and the fact it's free is a major bonus. I use the app all the time, but must confess that i've never used the GoB viewer site from my laptop - very handy thanks.