General:
Common Name: The Tripe Lichens. Alludes to the general resemblance of the species to certain “Rocktripes” of the genus Umbilicaria.
Minute stratified foliose lichens, corticate above and below, lacking isidia and soredia, lobes attached to substrate by a more or less central holdfast, rotund to subrotund, thallus averaging to 0.8–3.0 mm across, rather thick. Upper and lower surfaces brownish black, shiny, lacking rhizines. Medulla white. Photobiont blue-green.
Apothecia located over upper surface, immersed, perithecia-like (blackish dots as seen from above); spores simple, oval, colourless, 16 per ascus (in BC).
Notes: Phylliscum is a primarily temperate genus of approximately six species, only one of which is known to occur in North America.

Reactions:
All spot tests negative

Contents:
No lichen substances reported.

Source:  Lichens of British Columbia

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 By:  Trevor Goward

Synonyms and Alternate Names:
Thyrea demangeonii (Moug. & Mont.) Fink