<  Scytinium polycarpum
Solorina crocea  >
Click on Characteristic name for explanation. Click on image for larger version.
Scytinium rivale

PNW Range:
  West sideOccasional
  East sideUncommon
  Immediate coastRare
  Alpine or subalpineOccasional
Habitat: Small to medium sized streams in the mountains, in or near water, submerged much of the year.
Substrate: Noncalcareous rock, rarely on hard submerged wood.
Synonymy: Leptogium rivale
Scytinium rivale - Habit
by B. McCune
Scytinium rivale - Thallus section
Thallus section
by B. McCune
Scytinium rivale - Habit
by B. McCune
Scytinium rivale - Habit
by B. McCune
Scale: Bar=1mm unless noted
Growth Form
Fruticose: Never
Foliose: Almost always
Crustose: Never
Appressed Foliose: Almost always
Fluffy Foliose or Strappy: Never
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): 0.6 (± 0.3)

Upper Surface
Upper Surface Color    (Dry) 
   Pale Gray: Sometimes
   Dark Gray: Almost always
   Black: Rarely
   Brown: 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: Never
Lower Surface (Foliose)
Lower Surface Color    (Dry) 
   Dark Gray: Almost always
   Black: Almost always
   Brown: Almost always
Veined Below: Never
Rhizinate Below: Never
Tomentose Below: Never
Cyphellae: Never
Pseudocyphellae Below: Never
Papillae Below: Never

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

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

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

Asexual Reproduction
Isidia: Never
Soredia: Never
Lobules: Never