<  Parmeliopsis hyperopta
Parmotrema crinitum  >
Click on Characteristic name for explanation. Click on image for larger version.
Parmotrema arnoldii

Overview
PNW Range:
  West sideUncommon
  East sideNone
  Immediate coastAbundant
  Alpine or subalpineNone
Habitat: Coastal conifer forests and scrub; infrequent in Willamette Valley and Cascades.
Substrate: Bark and wood, rarely rock.
Comments:
Synonymy: none
Parmotrema arnoldii - Habit
Habit
by B. McCune
1/3
Parmotrema arnoldii - Habit
Habit
by B. McCune
2/3
Parmotrema arnoldii - Habit
Habit
by B. McCune
3/3
Scale: Bar=1mm unless noted
Growth Form
Fruticose: Never
Foliose: Almost always
Crustose: Never
Appressed Foliose: Sometimes
Fluffy Foliose or Strappy: Commonly
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): 8 (± 4)

Upper Surface
Upper Surface Color    (Dry) 
   Pale Gray Green: Almost always
   Pale Green: Rarely
   Whitish: Sometimes
   Pale Gray: Almost always
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: Almost always
Lower Surface (Foliose)
Lower Surface Color    (Dry) 
   Black: Almost always
   Brown: Sometimes
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
Medulla KC+ Orange, Red, or Pink: Almost always
Medulla UV+ Blue White: Almost always
Sexual Reproduction
Perithecia: Never
Apothecia: Rarely
   Mazaedium: Never
Disk Color    (Dry) 
   Disk Brown or Tan: Almost always

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