Tuesday, 28 April 2015
Lejeunea patens (Pearl Pouncewort)
Lejeunea patens is uncommon in VC41. As far as I can tell, the most recent record was made by Sam and Graham (2010) for Sgwd Gwladys in the Pyrddin Valley, where it grows as an epiphyte on Oak. The only other records (1960s) are for Craig y Llyn, where it grows on rock. So it was nice to find these plants growing as epiphytes on willow in the conifer plantation above Pentreclwydau (between Resolven and Glyn Neath).
Lejeunea patens has a distinctive, large lobule that makes a sharp, acute angle with the leaf, which differentiates it from the much more common L. lamacerina (the most common Lejeunea in NPT).
Lejeunea cavifolia has smaller lobules, but the 2 species are best distinguished by their cellular oil bodies. While cavifolia usually has a large number (25+) of small oil bodies, patens has few (up to 8) and they are larger.
The colonies have a distinct pale lustre in certain light, so the common name is rather apt.