Allantoparmelia alpicola (aka “Rock Grub Lichen”)
Location Summary
Substrate: On rock.
Identification Characteristics
Description: Thallus dark brown to almost black, frequently gray in older parts; lobes usually short, up to 1.5 mm broad; lower surface pale to dark brown or black; loosely to tightly adnate, occasionally cushion-like, to 7(12) cm diameter; convex, & often nodulose; upper surface lacking pseudocyphellae, soredia, & isidia, but often lobulate; lower surface generally folded or irregular; attached by irregular holdfasts; medulla P+Y, C- or C+R, KC+R
Chemistry: Medulla PD+ deep yellow, KC+ red, C- or C+ pink (alectorialic & barbatolic acids).
Range: Subalpine to alpine; circumpolar south to Washington & Montana; fairly common
Lookalikes: very similar to Brodoa in color & overall appearance, but the lobes are broader & shorter, & the chemistry is different. Allantoparmelia almquistii is a rarer arctic-alpine lichen with distinctly flattened, narrower lobes (usually less than 0.5 mm across) becoming entangled & producing slender lobules near the thallus center. In appearance, it is midway between a flattened morphotype of Pseudephebe minuscula & Allantoparmelia alpicola. Melanelia stygia is also a similar species of Allantoparmelia but has conspicuous pseudocyphellae & rhizines. Melanelia panniformis is thin & flattened at the growing margin, producing rounded, imbricate lobules only on the older thallus portion. Chemistry easily differentiates them: A. almquistii has a C+ red, PD- medulla (olivetoric acid); Pseudephebe is PD-, C- (no substances); Melanelia stygia can be PD+ red (fumarprotocetraric acid) or PD- & is always C- ; M. panniformis is PD-, C- (perlatolic acid); in Brodoa, the cortex is K+ yellow (atranorin) & the medulla is KC+ pink (lobaric acid) & either PD- or PD+ red-orange (protocetraric acid). See also Protoparmelia.
Bibliography: Lichens of North America, by Brodo, Sharnoff, & Sharnoff, Macrolichens of the Pacific Northwest, by Bruce McCune & Linda Geiser
Database Entry: Distance Everheart 12-26-13