Ahtiana sphaerosporella (aka Parmelia sphaerosporella, “Mountain Candlewax Lichen”)
Habitat: Subalpine forests to isolated trees at timberline, occasionally in lower elevation montane forests.
Description: Thallus dull, pale yellowish green, often with dark greenish black margins & blackening in exposed habitats; lower surface pale tan. Large, pale brown apothecia generally common on upper surface, the disk pale brownish or greenish or darkening. Frequently tightly wrapped around small twigs or tightly appressed to larger stems. Thin, rounded lobes about 2-4 mm across, with wrinkles & folds covering the upper surface; with short, slender, often branched, woolly rhizines; lacks pseudocyphellae, soredia, & isidia; pycnidia black, laminal, immersed or slightly protruding; spot tests negative except KC + Y cortex.
Northwest Territories south to California, inland to Montana & Alberta.
Substrate: Bark & wood of conifers. White -bark pine & subalpine larch in intermontane, subalpine localities.
Lookalikes: Cetraria pallidula can be similar in colour, but is suberect, has mainly marginal & submarginal pycnidia, & is not known to occur in the subalpine like Ahtiana sphaerosporella. Also looks like a very appressed Flavoparmelia caperata without soredia, but Flavoparmelia has a lower surface & is rarely fertile.
Bibliography: Macrolichens of the Pacific Northwest, by Bruce McCune & Linda Geiser, Lichens of North America, by Brodo, Sharnoff, & Sharnoff
Database Entry: Distance Everheart 12-26-13