Fauna
Fungus

Common Toadskin Lichen

Lasallia papulosa

Also known as Toadskin Lichen, Pustulate Rock Tripe, Blistered Rock Tripe

Common toadskin lichens cling tenaciously to sheer granite and sandstone faces by a single central anchor called an umbilicus. Their blistered, warty upper surfaces shift dramatically with moisture, transforming from brittle, ashen grey in drought to pliable, vibrant olive-green after rainfall. Growing at a pace of mere millimeters per decade, these long-lived symbiotic organisms slowly dissolve rock minerals and pioneer primary soil formation.

LichenRock DwellerSymbiotic
Common Toadskin Lichen reference1 / 7
(c) Zac Peterson, some rights reserved (CC BY) · cc-by
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Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Key facts
Diet & preySunlight, Atmospheric moisture, Windblown mineral dust
Predators
  • Oribatid mites
  • Slugs
  • Land snails
ThreatsAirborne sulfur dioxide pollution, trampling by rock climbers, and quarrying
HabitatsExposed siliceous boulders, granite outcrops, and sheer cliff faces
Life span50–100+ years
Classification
  1. OrderUmbilicariales
  2. FamilyUmbilicariaceae
  3. GenusLasallia
  4. SpeciesLasallia papulosa
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Many wild fungi have toxic look-alikes; never ingest wild specimens based on app identification alone.
Responsible observation
  • Hydration Effect: Mist dry thalli with water to watch them rapidly soften and turn green within minutes.
  • Leave Undisturbed: Avoid peeling specimens off rock surfaces, as they require decades to regrow.
Related species
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