Lepraria, Acharius, 1803

KEY 2: Key to Lepraria in Colorado (excluding fruticose forms):

1a. Thallus aggregate................................................................................................................................................................................2

1b. Thallus placodioid ..............................................................................................................................................................................6

2a. Thallus shades of white-blue-gray......................................................................................................................................................3

2b. Thallus shades of yellow-green..........................................................................................................................................................5

3a. Thallus with long, persistent, projecting hyphae persistent at maturity, primarily on mosses and soil, K+ yellow, C-, KC-, P-, UV- (atranorin, nephrosteranic acid)................................................................................................... L. rigidula (B. de Lesd.) Diederich

3b. Thallus lacking long, projecting hyphae persistent at maturity, chemistry various ...........................................................................4

4a. Thallus primarily mound forming, often consisting of (at least in part) large, pseudocorticate granules that exceed 1 mm in diameter, almost invariably on alpine soil where it sometimes forms monodominant stands, K- or K+ yellow, C-, KC-, P- or P+ yellow, UV- (atranorin, roccellic/angardianic acid, porphyrilic acid, fatty acids)............................... L. alpina (B. de Lesd.) Tretiach & Baruffo

4b. Thallus never mound-forming, lacking large, pseudocorticate granules that exceed 1 mm in diameter, primarily in lower montane to subalpine habitats (rarely in the alpine), on mosses, soil, and non-calcareous rocks, K+ yellow or K-, C-, KC- or KC+ red, P+ yellow or orange, UV- (chemistry various, but always P+) ..................................................................... L. neglecta (Nyl.) Erichsen

5a. Thallus with distinct yellowish hue, uncommon on bark, soil, mosses, and rocks, K- or K+ red, C-, KC-, P+ orange, UV- (dibenzofurans, oxypannaric acid-2-methylester) .......................................................................... L. diffusa (J.R. Laundon) Kukwa

5b. Thallus with greenish hue, widespread on on non-calcareous rocks, soil, mosses, lignum, and tree bases, K+ yellow or K+ yellow to red, C-, KC-, P+ yellow or P+ orange (atranorin, zeorin, +/- stictic acid aggregate, roccellic/angardianic acid, salazinic acid) ... ............................................................................................................................................................................. L. elobata Tønsberg

6a. Thallus KC+ pink or red, on soils, mosses, and trees, sometimes forming large stands especially under rock overhangs, K-, C-, P+ yellow or orange, UV- (alectorialic acid, +/- barbatolic acid, +/- protocetraric acid).......................................................................... ................................................................ L. eburnea J.R. Laundon (*take care to carefullyy find placodioid portions of the thallus under magnification, which can sometimes superficially appear as aggregate and therefore could be mistaken for Lepraria elobata )

6b. Thallus KC- ........................................................................................................................................................................................7

7a. Thallus (entirely) shades of white-blue-gray, never with yellow to green portions, with highly distinctive rounded margins and raised lip, on non-calcareous rocks, conifers, and hardwoods, K+ yellow, C-, KC-, P+ orange, P+ red, or P-, UV- (atranorin, roccellic/angardianic acid, +/- protocetraric acid)....................................................... L. normandinoides Lendemer & R.C. Harris

7b. Thallus shades of yellow to green, at least in part (thallus often gray to white in center but always yellow to green elsewhere, particularly along the margins)...........................................................................................................................................................8

8a. Thallus often rosette forming, with highly distinctive rounded, crisped margins that have raised lips ascending well above the primary plane of the thallus (aff. L. normandinoides ), these margins distinctively a sunny yellow in color, occuring over a wide variety of substrates but preferentially on soft substrates (e.g., soft rocks such as sandstones and over mosses), in exposed, arid microhabitats but also in more sheltered environments, K+ yellow, C-, KC-, P+ orange to red, UV- (atranorin, roccellic/angardianic acid, pannaric acid 6-methyl ester, pannaric acid, unknown dibenzofuran A, and occasionally pannaric acid 2-methyl ester........... ............................................................................................................................................ L. saliersiae E. Tripp & J. Watts , sp. nov.

8b. Thallus rarely rosette forming, lacking raised lips, thallus and margins only inconspicuously faint yellow at most, more commonly with a greenish to bluish hue, growing on wide variety of substrates in moist to drier habitats and from forested to urban ecosystems, K+ yellow-brown, C-, KC-, P+ orange, UV-, (atranorin, zeorin, stictic acid aggregate, +/- roccellic/angardianic acid).................... ....................................................................................................................................................... L. finkii (B. de Lesd.) R.C. Harris