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Physcia dubia

Overview
PNW Range:
  West sideOccasional
  East sideCommon
  Immediate coastUncommon
  Alpine or subalpineCommon
Habitat: Rock outcrops and talus in a wide variety of habitats, but most common in continental to suboceanic climates.
Substrate: Generally on rock or mosses over rock.
Comments:
Synonymy: none
Physcia dubia - Thallus transverse section
Thallus transverse section
by B. McCune
1/7
Physcia dubia - Lobes
Lobes
by B. McCune
2/7
Physcia dubia - Habit
Habit
by B. McCune
3/7
Physcia dubia - K test
K test
by B. McCune
4/7
Physcia dubia - Habit
Habit
by B. McCune
5/7
Physcia dubia - Soralia
Soralia
by B. McCune
6/7
Physcia dubia - Lower
Lower
by B. McCune
7/7
Scale: Bar=1mm unless noted
Growth Form
Fruticose: Never
Foliose: Almost always
Crustose: Never
Appressed Foliose: Commonly
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): 1 (± 0.5)

Upper Surface
Upper Surface Color    (Dry) 
   Pale Gray Green: Almost always
   Pale Green: Rarely
   Whitish: Almost always
   Pale Gray: 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: Almost always
   Tan: Almost always
Veined Below: Never
Rhizinate Below: Almost always
   Rhizines Squarrose: Never
Tomentose Below: Never
Cyphellae: Never
Pseudocyphellae Below: Never
Papillae Below: Never

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

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

Chemistry
Cortex K+ Yellow: Almost always
Sexual Reproduction
Perithecia: Never
Apothecia: Rarely
   Mazaedium: Never
Disk Color    (Dry) 
   Disk Black: Almost always

Asexual Reproduction
Isidia: Never
Soredia: Almost always
Lobules: Never