Target species for today was Preissia quadrata, a close relative of the ubiquitous Marchantia polymorpha:
Preissia quadrata is rare in the Warrington area because it prefers calcareous rocks and soils, which we don’t have much of. The Mucky Mountains, though, have exactly the right conditions created by tipping of alkaline waste from the Vitriol Works through til the mid-1800s. 150 years later the waste has weathered and been colonised by all sorts of interesting wildlife.We went to see whether we could refind the Preissia after a top tip from Peter Gateley as to where he had seen it last. And also to test our nerve and our ID skills on the many small acrocarps present around the site:
I still have some “homework” to look at from this site, but it was particularly nice to find and key out Bryoerythrophyllum recurvirostratum after studying it on the BBS Acrocarps weekend. We saw all three common species of Metzgeria, the epiphytic ribbon-like thallose liverwort.
And we found the Preissia!
Even the most unpromising-looking sites can hold interesting species – that’s one of the most addictive things about bryology.