Lichen: Parmotrema perlatum
Name: Parmotrema perlatum (Huds.) M.Choisy (1952)
Pronunciation: Parmotrema perlatum
Conservation Evaluation: Least Concern
Body Type: Foliose
Description: A leafy or foliose lichen with a grey-green thallus that is loosely attached to branches or rocks. A single specimen can grow to about 15 cm in size. The lobes that make up the thallus are up to 15 mm in wide. The edges of the lobes are wavy and raised up from the substrate and contain soralia. The underside is black towards the centre and the region towards the edge of a lobe is rich brown in colour. The edge itself is a characteristic black, giving rise to the popular name of ‘black-edged leaf lichen’.
The surface of the thallus is smooth with black cilia (up to 2 mm length and sometimes forked). Apothecia are rare.
Chemical Tests: K+ yellow, P+ orange, KC+ orange, UV-.
Nature Notes: Widespread in Ireland and particularly abundant in the south and west. It prefers acid bark or silica-rich rocks in well lit areas. It is sensitive to sulphur dioxide (SO2). Once known as Parmotrema chinense. Frequently abundant on hawthorn.
Vice county distribution map: See Map
Link: Map this species on the Lichen Survey
Other species recorded in Ireland:
- Parmotrema arnoldii (Du Rietz) Hale
- Parmotrema crinitum (Ach.) M.Choisy
- Parmotrema perlatum (Huds.) M.Choisy
- Parmotrema reticulatum (Taylor) M.Choisy
- Parmotrema robustum (Degel.) Hale
Text and images © Paul Whelan, 2009.