SafePlants

Xanthoria parietina: A Sunburst of Color

Xanthoria parietina, also known as common orange lichen, yellow scale, maritime sunburst lichen, or simply orange lichen, is a visually striking foliose lichen known for its vibrant hues.

Considerations for Pets:

• Lichens like Xanthoria parietina can grow on rocks, concrete, and trees, sometimes near cattle farms.

Considerations for Children:

• The pigments in orange, red, and brown lichens can be extracted by boiling and used to dye wool and other fibers.

Taxonomy and Nomenclature

• Scientific Name: Xanthoria parietina
• Common Names: Common orange lichen, yellow scale, maritime sunburst lichen, orange lichen, sunburst lichen.
• Genus: Xanthoria
• Family: Teloschistaceae
• Synonym: Xanthoria elegans (elegant sunburst lichen)

Distribution and Habitat

• Xanthoria parietina has a wide distribution and can be found in various locations.
• It grows on rocks, concrete, and trees.
• It can be found near cattle farms.
• Common on coastal rocks in New Zealand.

Morphological Characteristics

• It is a foliose (leafy) lichen.
• Forms large, rounded patches up to 10 cm across.
• Possesses wide, round-lipped marginal lobes.
• The thallus (body) is yellowish green to orange, sometimes grey in shade.
• Fruiting structures (apothecia) are usually present with a dark orange disc surrounded by a lighter edge.

Ecological Role

• Xanthoria parietina is a common lichen that can be especially prolific.
• Orange lichens also identify hunting perches of birds and grow in profusion in seabird
• Lichens are formed from a symbiotic association between a fungus and an alga. The alga is contained within the hyphae.

Quirky Facts

• The orange color of this lichen is due to the production of the pigment parietin.
• An orange pigment found in lichens and rhubarb called parietin may have potential as an anti-cancer drug.
• The depth of orange lichen growth often correlates with its position above the salt lichen area.

Interactions with Other Organisms

• The presence of orange lichens, including Xanthoria parietina, can indicate the hunting perches of birds.
• Lichens favour naturally alkaline bark with a pH between 4 and 7.

Further Information

• Microchemical Methods for the Identification of Lichens by Alan Orange provides a guide to chemical use and precautions.
• Symbol: CALOP7 for a general information database.