Lecanora stenotropa
Lecanora stenotropa is a widely distributed species of saxicolous crustose lichen in the family Lecanoraceae. It was described as new to science in 1872 by the Finnish lichenologist William Nylander.
Description
Lecanora stenotropa has a thallus composed of scattered to partially merging rounded. These granules occasionally form a more or less continuous crust. The thallus typically appears brown-green to green-grey in colouration. The lichen may have a black or none at all.The reproductive structures, called apothecia, typically measure 0.4–0.8 mm in diameter, though specimens with larger apothecia have been documented elsewhere. These apothecia are and can be found either scattered or densely clustered, in which case they may become angularly compressed where they meet. The is entire to , white to grey in colour, barely raised, and may become almost excluded as the apothecium matures. The at the centre of each apothecium is pale brown to grey-brown, flat to slightly convex, and lacks .
Internally, the is colourless and. The hymenium measures 45–60 μm in height, though thinner measurements have been reported elsewhere. The paraphyses are 1.5–2 μm in diameter, unbranched or sparsely branched, with slightly swollen tips. The measure 8–12 by 3–4 μm and are narrowly ellipsoidal in shape.
When tested with common chemical spot tests used in lichen identification, the species is C− and K−, Pd−, UV−, and either a weakly positive yellow reaction or no reaction to KC. The lichen contains usnic acid, isorangiformic acid, and zeorin.