vs common grey sea slug

Chrysothrix candelaris compared with Aeolidia papillosa

Taxonomic Classification

Rank		common grey sea slug
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Ascomycota (Sac Fungi)	Mollusca (Mollusks)
Class	Arthoniomycetes (Arthoniomycetes)	Gastropoda (Gastropoda)
Order	Arthoniales (Arthoniales)	Nudibranchia (Nudibranchia)
Family	Chrysotrichaceae	Aeolidiidae
Genus	Chrysothrix	Aeolidia
Species	Chrysothrix candelaris	Aeolidia papillosa

Conservation Status

LC — Least Concern

common grey sea slug

LC — Least Concern

Physical Characteristics

Attribute		common grey sea slug
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

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

Range

Found across Europe (4 countries) and South America (Brazil, Colombia).

common grey sea slug

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Distributed across Belgium, Chile, Denmark, Norway, and Sweden.

Chrysothrix candelaris, commonly known as the gold dust lichen or egg yolk lichen, is a distinctive sorediate crustose lichen formed by the mutualistic association of a fungal partner (Chrysothrix candelaris, class Arthoniomycetes) with green algal photobionts. The lichen is immediately recognizable by its bright chrome-yellow to yellow-orange powdery soredia — granular reproductive propagules — which form a continuous farinose crust on the bark of acidic-barked trees, rock surfaces, and decaying wood in shaded, humid conditions. The vivid yellow color is due to calycin and other xanthone pigments. C. candelaris is widely distributed across Europe, North America, and South America, growing on smooth-barked deciduous and coniferous trees, boulders, and cliff faces in woodland and boreal forest habitats. It is assessed as Least Concern by the IUCN, reflecting its broad distribution and tolerance of a range of microhabitats. The lichen serves as a bioindicator of old-growth forest conditions and is sometimes used in air quality monitoring, as it is moderately sensitive to sulfur dioxide pollution. C. candelaris reproduces vegetatively through the dispersal of soredia by wind, water, and animals, which carry photobiont and mycobiont cells together.

common grey sea slug

<em>Aeolidia papillosa</em>, commonly known as the common grey sea slug, is a nudibranch mollusc belonging to the genus Aeolidia within the family Aeolidiidae. Despite the species name referencing terrestrial and aquatic habitats including forests and freshwater, <em>Aeolidia papillosa</em> is primarily a marine organism. Its range includes Belgium, Chile, Denmark, Norway, and Sweden, indicating a distribution across the North Atlantic and into South American waters. Common grey sea slug is assessed as Least Concern on the IUCN Red List. The species is typically found in intertidal and subtidal zones, where it preys on sea anemones and stores stinging cells from its prey in its dorsal cerata for defense. Biological traits of this species remain poorly documented in the scientific literature.