Lecanora ecorticata J. R. Laundon, Nova Hedwigia 76, 100–102 (2003).—Lepraria ecorticata (J. R. Laundon) Kukwa, Mycotaxon97, 64 (2006); type: Great Britain, England, Devon (Vice- County (V.C.) 4), Ilfracombe, Torrs Walks, 21/50.47, on shaded vertical rocks, 1 September 1971, J. R. Laundon 2851 (BM—holotype [lost]) [Thin-layer chromatography: atranorin, usnic acid and zeorin, according to the protologue]; Wales, V.C. 49, Caernarvonshire, Beddgelert, Bethania, 2.25 miles south of Snowdon, SH626.509, abundant on underhang of wall running alongside a rough track, 30 April 1983, R. O. Millar (BM – 000763146—lectotype, designated here! MBT 393476) [Thin-layer chromatography: usnic acid, some terpenoids (in traces), 2005, Martin Kukwa].
Description
Thallus crustose, diffuse, often forming large colonies, arising from aggregations of separate granules to form a leprose crust, pale yellow-green (Munsell 5GY 7–8/2), becoming blue-grey in deep shade; thallus eventually up to 2mm thick, but then most of the thickness is of dead decolourized granules; thicker thalli may become cracked; granules fine, 60–100 μm diam., ecorticate, without projecting hyphae. Medulla and hypothallus absent. Prothallus absent or occasionally sparsely present in shade.
Ascomata and conidiomata unknown.
Chemistry. Unidentified terpenoid A at Rf class 6 in solvent system G, dirty grey-brown after heating, UV+ dull pink (minor), additional trace of a terpenoid at Rf class 6, immediately below usnic acid; two fatty acids, Rf class 4–5 in G (major or minor), appearing as a single spot Rf class 6 in solvent system A, traces of additional fatty acids; usnic acid (major); atranorin (accessory, minor). Zeorin is absent. Thallus K−, C−, KC+ pale yellow, PD−.
Ecology. On rain-sheltered siliceous rocks, extending further into sheltered cavities than most other lichens, and typically forming pure stands.