General:
Common Name: The Starburst Lichens. Describes the centrifugal growth pattern characteristic of the species.
Small stratified foliose lichens, corticate above and below, sorediate, lobes closely appressed, elongatelinear to elongate, averaging to 1–2 mm wide, thin. Upper surface whitish grey or pale yellowish green, more or less shiny, especially at lobe tips. Lower surface pale brown to blackening, bearing short, simple rhizines. Medulla white. Photobiont green.
Apothecia located over upper surface, disc brown; spores simple, sausage-shaped, colourless, 8 per ascus.
Notes: Parmeliopsis is a boreal–temperate genus consisting of three species worldwide. All of these occur in North America, though only two are present in B.C.

Species description:
Upper surface whitish; soredia present or absent AND
Isidia absent; soredia present; over bark or rock AND
Upper surface somewhat shiny near lobe tips; over acid bark; medulla KC+ rose

Reactions:
Cortex K+ yellow.

Contents:
Atranorin and divaricatic acid.

Source:  Lichens of British Columbia

Synonyms and Alternate Names:
Foraminella hyperopta (Ach.) S. F. Meyer
Parmeliopsis diffusa (Weber) Riddle