Fungus
Lesser Rocktripe
Umbilicaria muhlenbergiiAlso known as Plated Rock Tripe, Muhlenberg's Rock Tripe
Lesser rocktripe clings to exposed granite boulders and vertical rock faces by a single central cord called an umbilicus. Its leathery, plate-like thallus features a distinctive cracked and pitted upper surface that curls inward during dry spells, exposing a darker underside to reduce moisture loss. When rehydrated by mountain mists or rain, the lichen quickly softens and resumes photosynthesis through its symbiotic green algal partners.
LichenSaxicolousCold-Hardy
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—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & preyPhotosynthetic (via green algal photobiont)
Predators
- Springtails
- Oribatid mites
- Land snails
ThreatsAir pollution, heavy rock-climbing traffic, wildfire
HabitatsExposed acidic rock outcrops, granite cliffs, boulder fields
Life spanDecades to centuries
Classification
- OrderUmbilicariales
- FamilyUmbilicariaceae
- GenusUmbilicaria
- SpeciesUmbilicaria muhlenbergii
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Many edible wild fungi have toxic look-alikes; never eat wild fungi based on app identification alone.
Responsible observation
- Field Inspection: Gently lift the outer edge to view the single central stalk anchoring it to stone.
- Moisture Check: Observe how brittle, dry thalli instantly turn supple and olive-green after rain.
Same Genus (c) Michael J. Papay, some rights reserved (CC BY), uploaded by Michael J. Papay · cc-by
Image unavailableSame Genus 
Competitor (c) Jeffrey Lee (he/him/his), some rights reserved (CC BY) · cc-by
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