SafePlants

Rimmed Lichens and White-Rimmed Lichens: A Botanical Overview

This page explores various lichens characterized by distinct rims or overall white coloration, providing insights into their scientific classifications, habitats, and unique features.

Considerations for Pets

• Some lichens, such as *Asphodelus albus*, are herbaceous perennials. Note that the presence of rhizomes in the soil may pose a digging interest for some pets.

Considerations for Children

• Lichens often grow on rocks and trees. Children may encounter these organisms during outdoor play.
• The text mentions terms like "apothecia" and "isidia," which refer to reproductive structures. Discussing these with children can be a valuable learning opportunity.

Common Names

• Rim Lichen
• White Rim Lichen
• Calcareous Rimmed Lichen
• Rimmed Shingle Lichen
• White-rimmed Shingle Lichen
• Rimmed Navel Lichens
• White Rock-posy

Scientific Names and Taxonomy

• Aspicilia: A genus within the family Hymeneliaceae.
• Ochrolechia oregonensis: A species of lichen with peach-colored disks.
• Cryptothecia rubrocincta: A species of lichen in the Arthoniaceae family of fungi.
• Fuscopannaria leucosticta: Also known as White-rimmed Shingle Lichen. Belongs to the Kingdom Fungi, Phylum Ascomycota, and Class Lecanoromycetes.
• Rhizoplaca: A genus of lichens known as Rimmed Navel Lichens.
• Anzia: This genus includes species such as *Anzia mahaeliyensis* and *Anzia flavotenuis*, which are new lichen species from Sri Lanka.
• Lecanora rupicola: Also known as White Rim Lichen, with synonyms including *Glaucomaria rupicola* and *Lecanora sordida*.
• Asphodelus albus: Also known as White Asphodel.
• Caloplaca cerina: Also known as Gray-rimmed Firedot Lichen.

Distribution and Habitat

• Lichens are found on various substrates including limestone rock, mortar sculptures, tree bark (such as oak, poplar, and aspen), and concrete.
• Specific locations mentioned include the Alps maritime and Pyrenees in France, Sri Lanka, and the Pacific Northwest.

Morphological Characteristics

• Lichens exhibit diverse growth forms, including crustose (forming a crust on the substrate), foliose (leaf-like), and areolate (divided into small areas).
• Some lichens have apothecia (fruiting bodies) that are black, brown-black, or blue-black, sometimes covered with a bluish-white pruina (a powdery surface coating).
• The apothecia can be rimmed, with colors including white, gray, or orange.
• Some lichens develop isidia (small, vegetative propagules).
• *Asphodelus albus* is a clump-forming, rhizomatous, herbaceous perennial.

Interactions with Other Organisms

• Lichens represent a symbiotic relationship between fungi and algae or cyanobacteria.
• Lichens can provide habitat for other organisms, with mentions of their presence alongside mosses, vascular plants, mammals, reptiles, arthropods, and molluscs.

Quirky Facts

• Lichens have been described as "fungi that have discovered farming" due to their symbiotic relationship with algae or cyanobacteria.

Further Information

• Lichen Vocabulary: A discussion of lichen growth forms and structures.
• Calkins's 1896 work on the lichen flora of the Chicago region.