SafePlants

Xanthoria parietina: Common Orange Lichen

Xanthoria parietina is a foliose lichen with a wide distribution. It is commonly known as common orange lichen, yellow scale, maritime sunburst lichen, orange lichen, and sunburst lichen.

Considerations for Pets

• Grows on rocks, concrete and trees.
• Prefers areas with ammonia.

Taxonomy and Nomenclature

• Scientific Name: Xanthoria parietina
• Common Names: Common orange lichen, yellow scale, maritime sunburst lichen, orange lichen, sunburst lichen, golden shield lichen, shore lichen.
• Family: Teloschistaceae
• Xanthoria is a genus of lichenized fungi

Distribution and Habitat

• Widely distributed.
• Found on rocks, concrete, and trees.
• Common on coastal rocks in New Zealand (Xanthoria ligulata mentioned as a related coastal species).
• Also found in mountainous areas (e.g., covering a boulder) and near cattle farms.

Morphological Characteristics and Growth Habits

• Foliose (leafy) lichen.
• Forms large, rounded patches up to 10 cm across.
• Has wide, round-lipped marginal lobes.
• Thallus color ranges from yellowish-green to golden-yellow or orange, and may appear grey in shade.
• Lacking isidia or soredia.
• Apothecia (fruiting bodies) are usually present with a dark orange disc surrounded by a lighter edge.
• Orange or yellow lichens that grow in shade may appear green, while grey lichens are possible.

Ecological Role

• Orange lichens also identify hunting perches of birds and grow in profusion in seabird

Interactions with Other Organisms

• A symbiotic association between a fungus and an alga. The alga is contained within the hyphae.
• Orange lichens also identify hunting perches of birds and grow in profusion in seabird

Quirky Facts

• The orange color is due to the production of the pigment parietin.
• Pigments can be extracted by boiling and used to dye wool and other fibers.
• Parietin may have potential as an anti-cancer drug.
• Lichens can survive harsh weather that would kill a fungus or an alga growing
• The intensity of col in lichens often varies, particularly with the amount of sun or rain

Further Information

• Microchemical Methods for the Identification of Lichens by Alan Orange (a guide to chemical identification methods).
• "Xanthoria parietina" page where Common orange lichen was marked as trusted.