Lichen: Parmelina pastillifera
Name: Parmelina pastillifera (Harm.) Hale (1976).
Old name: Parmelia pastillifera.
Pronunciation: Parmelina pastillifera
Conservation Evaluation: Least Concern
Body Type: Foliose
Description: The thallus (4-15cm wide) is composed of mineral grey lobes (3-10mm wide) that overlap a little. The lobes are pressed closely to the substrate (adpressed) and have rounded margins with small irregular indents. The margins are frequently pruinose. The under surface is black turning brown towards the margins; this brown tint may also be seen from the upper surface. Simple rhizines develop out to the lobe margin. The grey upper surface often takes on a blue tint with light blotches (maculae). Isidia are common and are a distinguishing feature. They appear as small blue-black to black mushroom shaped structures sometimes fusing into large black clumps. The clumps of isidia may be scattered throughout the thallus or found in small groups, especially towards the centre of lobes. Apothecia and pycnidia are rare and have not been found on Irish specimens.
Chemical Tests: Cortex K+ yellow; Medulla C+ carmine red; K-, KC+ red, Pd-, UV-.
Nature Notes: Found on ash and other acid-bark trees especially in nutrient rich areas such as near farms. Also likes silica rich rocks and well lit areas such as roofs and town monuments.
Vice county distribution map: see map
Link: Map this species on the Lichen Survey
Other species recorded in Ireland:
Parmelina carporrhizans (Harm.) Hale
Parmelina tiliacea (Hoffm.) Hale
Text and images © Paul Whelan, 2010.