Lichen: Placidium squamulosum
Name: Placidium squamulosum (Ach.) Breuss (1996)
Was: Catapyrenium squamulosum (Ach.) Breuss (1985)
Pronunciation: Placidium squamulosum
Conservation Evaluation: Least Concern, Nationally Scarce.
Body Type: Squamulose.
Description: The thallus consists of flattened squamules brown to dark red on the upper side and paler on the underside. They form either in continuous side to side alignment (tightly adpressed) or they are scattered and range in size from 2 to 7mm across. The underside has tiny colourless rhizines. The margins may show a slight upturning. Perithecia are common but frequently fully immersed; the ostioles or openings are black.
Chemical Tests: None.
Nature Notes: Found on calcareous soils and rocks often in crevices with lots of humus. Common in the Burren and along the coast.
Vice County distribution map: See map.
Link: Map this species on: Lichen Survey
Other species recorded in ireland:
- Placidium pilosellum (Breuss) Breuss (1996)
- Placidium rufescens (Ach.) A. Massal. (1855)
Text and images © Paul Whelan, 2009.