SafePlants

Dot Lichen: A Diverse Group of Lichens

The term "dot lichen" is a common name applied to lichens belonging to the genera Arthonia and Micarea. "Dotted lichens" is also used as a common name for lichens in the genus Bacidia. This reflects their appearance, often characterized by small, dot-like structures on their substrate.

Considerations for Pets

• Substrate: Dot lichens can be found growing on bark, rocks, and other surfaces, potentially exposing pets to these materials in environments where the lichens are present.

Taxonomy and Nomenclature

• Family: Arthoniaceae
• Genera commonly referred to as Dot Lichens: Arthonia, Micarea, Bacidia
• Synonyms: The text mentions several species and their synonyms, but does not provide a comprehensive list of synonyms for the genera themselves. The text mentions Bacidia chlorococca as a synonym for Scoliciosporum chlorococcum (City Dot Lichen)

Distribution and Habitat

• Dot lichens are found in various environments, including on palm tree bark (e.g., Arthonia rubella in Florida), on rocks in mountainous regions, and on birchbark.
• One source notes the abundance of a lichen (likely a dot lichen) in the New Orleans area.

Morphological Characteristics

• Dot lichens, as the name suggests, typically appear as small dots on various surfaces.
• Mycobilimbia pilularis, a dot lichen, is described as a crustose lichen with a grayish-green thallus and yellowy-brown apothecia.
• Dibaeis absoluta (Pink Dot Lichen) has pink apothecia born on short stalks.
• Speckled Shield Lichens, like Punctelia bolliana, are grey foliose lichens with tiny white dots and lobules.

Specific Examples

• Birchbark Dot Lichen: (Leptorhaphis epidermidis and Leptorhaphis atomaria)
• Orange Dot Lichen: (Protoblastenia rupestris)
• Hidden Dot Lichen: (Japewia tornoensis)
• Pink Dot Lichen: (Dibaeis absoluta)
• City Dot Lichen: (Scoliciosporum chlorococcum)
• Frosty-rimmed Dot Lichen: (Bacidia rubella)
• Granite firedot lichen: (Caloplaca arenaria)
• Firedot lichen: (Caloplaca holocarpa)
• Multicolored dot lichen: (Cliostomum griffithii)
• Dispersed Dot Lichen: (Arthonia dispersa)
• Tuckerman's Dot Lichen: (Arthonia tuckermaniana)
• Nitschke's Dot Lichen: (Micarea nitschkeana)

Resources and Further Information

• Encyclopedia of Life
• Catalogue of Life
• USDA
• Smithsonian Institution, National Museum of Natural History, Department of Botany
• ResearchGate
• Various databases and checklists are mentioned (LSID, JSON, WMS, RDF, Catalogue of Life: 2012 Annual Checklist)