Lepraria malouina  

Description
Thallus entirely leprose, pale yellow-grey, 5–6 cm wide, cracked. Prothallus thin and scarcely visible, pale. Hypothallus thick, 0.6–0.8 mm high, pale, loosely organized, with the lowermost part brown to dark brown where the hyphae attach to the substrate. Hyphae hyaline, c 2 µm diam., + smooth, septate, often branched at septa. No marginal lip. Rhizohypahe absent. Granules 35–40 µm diam., no pseudocortex formed, with ±short, protruding hyphae.
Chemistry: Usnic acid (major), stictic acid complex (major).

Etymology:
Derived from the French name for the islands, Îles Malouines, named after the fishermen and mariners of St. Malo (France) who were the first to settle on the islands.

Distribution and Ecology.
Known only form rock on the Falkland Islands.

Comments.
The terminology of Lendemer (2011) is used. In South America, 30 species of Lepraria are currently recognized (Flakus & Kukwa 2007, Lendemer 2010, Elix et al. 2010, Flakus et al. 2011), none of which has the chemical content met with in the present species. Lepraria species with usnic acid (Lecanora ecorticata J.R. Laundon (syn. Lepraria ecorticata (J.R. Laundon) Kukwa), Lepraria coriensis (Hue) Sipman and L. usnica Sipman) belong to other genera, and do not form a monophyletic clade (Nelsen et al. 2008).