Order: Peltigerales Family: Collemataceae
Species: Leptogium plicatile
UK photographs. Identified by Brian Coppins
Variable. Convoluted dark olive-brown or red-brown thallus, loosely rosette-shaped, closely adpressed. Thick, tough, +/- ridged lobes with divided, pleated margins (most noticable when dry). Coarse, isidia-like warts are sometimes present, apothecia infrequent.
Found on hard, damp limestone and horizontal tombstones. Occasional on siliceous rock affected by calcareous seepage.
Similar: Collema auriforme. Becomes jelly-like when wet.
Leptogium plicatile February 2010