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Peltigera britannica  >
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Peltigera aphthosa

PNW Range:
  West sideUncommon
  East sideCommon
  Immediate coastUncommon
  Alpine or subalpineCommon
Habitat: Common in more continental climates east Cascades but largely replaced by P. britannica in low to mid-elevation moist forests west Cascades; frequent on roadcuts and in open outcrop and talus areas.
Substrate: Soil, forest floor, and mossy rocks.
Synonymy: none
Peltigera aphthosa - Habit
Growth Form
Fruticose: Never
Foliose: Almost always
Crustose: Never
Appressed Foliose: Sometimes
Fluffy Foliose or Strappy: Sometimes
Dangling Hair: Never
Erect Hair: Never
Appressed Hair: Never
Stalks With Squamules: Never
Stalks: Never
Squamules: Never
Single Holdfast: Never
Dangling Nets: Never
Lobe Width (mm): 30 (± 10)

Upper Surface
Upper Surface Color    (Dry) 
   Pale Gray Green: Almost always
   Pale Green: Almost always
   Dark Green: Almost always
   Olive Brown: Commonly
   Olive Green: Almost always
   Brown: Sometimes
   Tan: Sometimes
Upper Surface Tomentose: Never
Upper Surface Pruinose or Scabrid: Never
Upper Surface with Network of Ridges: Never
Upper Surface with Pseudocyphellae: Never
   Upper Surface with Holes into Cavity: Never
Cilia on Margins: Never
Lower Surface (Foliose)
Lower Surface Color    (Dry) 
   Whitish: Commonly
   Pale Gray: Commonly
   Dark Gray: Commonly
   Black: Commonly
   Brown: Sometimes
   Tan: Sometimes
Veined Below: Sometimes
Rhizinate Below: Almost always
   Rhizines Squarrose: Sometimes
Tomentose Below: Sometimes
Cyphellae: Never
Pseudocyphellae Below: Never
Papillae Below: Never

Inside (Medulla) Yellow or Orange: Never
Central Cord: Never
Hollow Stalks or Hollow Lobes: Never
Gelatinous: Never

Green Algae Primary Photobiont: Almost always
Cyanobacteria Primary Photobiont: Never
Internal Cephalodia: Never
External Cephalodia: Almost always

Sexual Reproduction
Perithecia: Never
Apothecia: Sometimes
   Mazaedium: Never
Disk Color    (Dry) 
   Disk Brown or Tan: Almost always

Asexual Reproduction
Isidia: Never
Soredia: Never
Lobules: Never