General:
Common Name: The Paw Lichens. Alludes to the presence of brown, paw-like apothecia on the lower surface; in all other genera the apothecia are located over the upper surface or along the lobe margins.
Small to medium or large stratified foliose lichens, corticate above and below, sorediate or isidiate or not, lobes loosely appressed to loosely attached, short to elongate, averaging to 0.5–2 (–3) cm wide, thin. Upper surface greenish, greyish or brownish, dull or shiny. Lower surface pale to dark, naked or more or less covered in dense woolly tomentum, occasionally also tuberculate, lacking rhizines. Medulla white (yellow to orange). Photobiont green and/or blue-green.
Apothecia appressed over lower surface near lobe tips, disc brown; spores 4-celled, spindle-shaped, pale brown, 8 per ascus.
Over trees, logs, mossy rocks.
Notes: Nephroma is a cosmopolitan genus of about 40 species worldwide. Nine are known from North America and all occur in B.C. Although thin-layer chromatography has been used successfully in the elucidation of some Nephroma species (see for example James and White 1987), spot tests are of little taxonomic value in this genus.

Species description:
Photobiont a grass-green alga; upper surface usually at least in part greenish (especially when wet: check sheltered lobes); soredia and isidia absent; over mossy rock or decaying logs; restricted to cool, snowy districts AND
Upper surface dull, greenish to brownish; internal cephalodia not visible from above; lower surface dark brown toward thallus centre; apothecia rare

Reactions:
All spot tests negative.

Contents:
Zeorin and various other triterpenoids (also various other substances).

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