Common Button Lichen vs Common Metad

Buellia erubescens compared with Millardia meltada

Key Differences

• Common Button Lichen is Not Evaluated while Common Metad is Least Concern.

Taxonomic Classification

Rank	Common Button Lichen	Common Metad
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Ascomycota (Sac Fungi)	Chordata (Chordates)
Class	Lecanoromycetes (Lecanoromycetes)	Mammalia (Mammals)
Order	Caliciales (Caliciales)	Rodentia (Rodents)
Family	Caliciaceae	Muridae (Mice & Rats)
Genus	Buellia	Millardia
Species	Buellia erubescens	Millardia meltada

Conservation Status

Common Button Lichen

NE — Not Evaluated

Common Metad

LC — Least Concern

Physical Characteristics

Attribute	Common Button Lichen	Common Metad
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Button Lichen

Habitat

Native to Asia and Europe and North America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway, Portugal, Sweden, Taiwan, and United States.

Common Metad

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Common Button Lichen

<em>Buellia erubescens</em>, commonly known as the common button lichen, is a lichen species with documented occurrences across Asia, Europe, and North America, including countries such as Norway, Portugal, Sweden, Taiwan, and the United States. It typically colonizes diverse terrestrial surfaces, often found on bark, rock, or other substrates in temperate and boreal environments. Common button lichen belongs to the genus <em>Buellia</em> within the family Caliciaceae. As a crustose lichen, it typically forms tightly adhered, crust-like thalli on the surfaces it colonizes, making it characteristic of stable, undisturbed substrates. Biological traits such as average lifespan, thallus size, and biomass of this species remain poorly documented in the scientific literature. The species has not yet been formally evaluated by the IUCN, and its global conservation status therefore remains undetermined. Its occurrence across multiple continents suggests a wide ecological tolerance, though detailed population data and trend assessments are currently lacking for this taxon.

Common Metad

The Common Metad (<em>Millardia meltada</em>) is a rodent belonging to the genus <em>Millardia</em> within the family Muridae. As a member of the Old World rats and mice, this species is typically found in diverse terrestrial and aquatic ecosystems across its range. The Common Metad is classified as Least Concern on the IUCN Red List, indicating that its populations are currently stable and not facing immediate extinction risk. Detailed biological traits such as body length, weight, and lifespan have not been widely documented for this species in available records. Its taxonomy places it within the order Rodentia, which encompasses a broad array of gnawing mammals adapted to a wide variety of ecological niches. While specific dietary habits are not well characterized in the available data, members of the genus <em>Millardia</em> are generally understood to be omnivorous, feeding on plant material and invertebrates typical of their habitat. Ongoing monitoring is important for ensuring this species maintains its current conservation standing.