SafePlants

Xanthoria parietina: The Common Orange Lichen

Xanthoria parietina is a widespread foliose lichen, easily recognizable by its vibrant color and leafy structure. Often found in coastal areas and even near cattle farms, this lichen adds a splash of color to diverse environments.

Common Names

• Common orange lichen
• Yellow scale
• Maritime sunburst lichen
• Orange lichen
• Orange wall lichen
• Sunburst lichen
• Golden Shield Lichen
• Shore Lichen

Taxonomy and Nomenclature

• Scientific Name: Xanthoria parietina
• Genus: Xanthoria
• Family: Teloschistaceae
• Note: Xanthoria elegans, commonly known as the elegant sunburst lichen, is a related species within the same genus.

Distribution and Habitat

• Xanthoria parietina exhibits a wide distribution.
• It is found on rocks, concrete, and trees.
• It is often found near coastal environments and cattle farms.
• Specific locations mentioned include the Western Isles, Humboldt Lagoons State Park in California, and Mount Washburn Trail in Yellowstone National Park, Wyoming.

Morphological Characteristics

• It is a foliose (leafy) lichen.
• It forms large, rounded patches up to 10 cm across.
• It has wide, round-lipped marginal lobes.
• The thallus (body) is yellowish green to golden-yellow or orange, and grey in shade.

Ecological Role

• Favors ammonia in the environment.

Interactions with Other Organisms

• Orange lichens identify hunting perches of birds.
• Grows in profusion in seabird colonies.

Considerations for Pets

• Grows on rocks, concrete and trees.

Considerations for Children

• Grows on rocks, concrete and trees.

Quirky Facts

• The intensity of the lichen's color can vary depending on the amount of sun or rain it receives. Shaded lichens may appear green, while sun-exposed ones are more intensely orange or yellow.
• The orange color is due to the production of the pigment parietin.

Traditional Uses

• Pigments of lichens, especially the orange, red, and brown ones, can be extracted by boiling and used to dye wool and other fibers.
• An orange pigment found in lichens and rhubarb called parietin may have potential as an anti-cancer drug.

Further Information

• "Microchemical Methods for the Identification of Lichens" by Alan Orange is a resource for identifying lichens.