Galapagos Species Database

Thallus corticolous, saxicolous or terricolous (in the Galapagos only one corticolous specimen is currently known), placodioid leprose, i.e., developing upon a common, shared hypothallus, delimited by a byssoid arachnoid, ‘cottony’ prothallus forming an irregular, not distinctly lobed margin, always lacking a distinct lip, not ‘crisped’; surface deeply grayish green, often with a bluish green tinge, in the herbarium fading to a pale yellowish green; hypothallus moderately to well developed, loose, ‘fluffy’, ‘cottony’, rhizohyphae sparse or absent; granules ecorticate, ill-defined, mealy [(20–)30–70(–100) µm in diam., fairly even in size but ±aggregating in larger clusters (up to 100 µm)], generally loosely packed, typically with some extruding hyphae. Photobiont green, coccoid. Spot tests and chemistry: P, K± sordid yellow, KC, C, UV+ bright yellowish white; zeorin and divaricatic acid. Distribution and Ecology. Cosmopolitan, but rarely reported from the tropics, in Galapagos known from a single collection only: in the agricultural area in the humid zone of Santa Cruz Island, close to the road, on bark of an introduced tree (Syzygium sp.). Notes. In South American records of L. aff. incana possibly refer to a cryptic, still undescribed species. Without molecular evidence it would be premature to describe the material as new.