Parmelia fraudans (Nyl.) Nyl.
Pea-green crottle
Parmeliaceae

Introduction to the Lichens

Photograph

© Curtis Bjork     (Photo ID #26563)


Map

E-Flora BC Static Map

Distribution of Parmelia fraudans unavailable

Species Information

General:
Medium stratified foliose lichens, corticate above and below, sorediate or isidiate or not, checkered pseudocyphellate (in BC), lobes loosely attached to rather closely appressed, elongate, averaging to 1.5–10 mm wide, thin. Upper surface whitish or pale greyish blue, somewhat shiny. Lower surface blackening, shiny, bearing short or rather long, simple or branched rhizines. Medulla white. Photobiont green. Apothecia located over upper surface, disc brown; spores simple, ellipsoid, colourless, 8 per ascus. Over rock and trees.

Notes: Parmelia is primarily a boreal and temperate genus consisting of 39 species worldwide. Eight of these are reported for North America and seven occur in B.C. As originally circumscribed by Acharius in 1803, Parmelia encompassed an enormous assemblage of foliose lichens, including Lobaria, Pannaria and Xanthoria. Beginning in the latter half of the 19th century, and apparently concluding only in the past decade, lichenologists have divided Parmelia into dozens of new genera, most of which are now widely accepted. Local species accommodated until recently in Parmelia are now dispersed among the following genera: Ahtiana, Arctoparmelia, Flavopunctelia, Hypotrachyna, Melanelia, Neofuscelia, Punctelia, and Xanthoparmelia.
Species description:
Soredia and/or isidia present (rarely sparse); ecology various AND Thallus isidiate; isidia hard and shiny or occasionally with soft, cottony appearance but never associated with soralia AND Rhizines unbranched or at most sparsely forking/dichotomous; distribution various AND Isidia “soft”, not at all hard-corticate, never shiny, generally short and granular; medulla K+ yellow becoming orange AND Upper surface faintly yellowish; isidia mostly marginal, densely clustered; over rock; inland
Reactions:
Cortex K+ yellow, medulla K+ yellow becoming red, PD+ orange.
Contents:
Atranorin, protolichesterinic acid, salazinic acid, usnic acid (soredia only).

SourceLichens of British Columbia

Illustration

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration ByTrevor Goward

Habitat and Range

Habitat: Frequent over acid rock in cool, somewhat sheltered inland localities

World Distribution: incompletely circumpolar, S to AZ.

SourceLichens of British Columbia