Collared Mosscap vs common sea hare

Rickenella swartzii compared with Aplysia punctata

Taxonomic Classification

Rank	Collared Mosscap	common sea hare
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Basidiomycota (Club Fungi)	Mollusca (Mollusks)
Class	Agaricomycetes (Mushrooms)	Gastropoda (Gastropoda)
Order	Hymenochaetales (Hymenochaetales)	Aplysiida (Aplysiida)
Family	Rickenellaceae	Aplysiidae
Genus	Rickenella	Aplysia
Species	Rickenella swartzii	Aplysia punctata

Conservation Status

Collared Mosscap

LC — Least Concern

common sea hare

LC — Least Concern

Physical Characteristics

Attribute	Collared Mosscap	common sea hare
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Collared Mosscap

Habitat

Typically found in forest floors, decomposing wood, and soil ecosystems.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

common sea hare

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Collared Mosscap

The Collared Mosscap, known scientifically as <em>Rickenella swartzii</em>, is a small fungus belonging to the family Repetobasidiaceae within the order Agaricales. <em>Rickenella swartzii</em> is characterised by its diminutive fruiting bodies, which typically feature a small, convex to umbilicate cap and a slender stipe. The species typically grows in mossy substrates, on forest floors, decomposing wood, and soil, where it plays a role in nutrient cycling as a saprotrophic or potentially mycorrhizal organism. It is reported to occur in Belgium, Denmark, Norway, and Sweden, reflecting a distribution across parts of northern Europe. Detailed biological traits including typical lifespan measures and physical dimensions are poorly documented for this fungal species in available literature. The Collared Mosscap is currently assessed as Least Concern on the IUCN Red List, indicating that it is not considered to be at significant risk of global population decline.

common sea hare

<em>Aplysia punctata</em>, the common sea hare, is a large opisthobranch sea slug in the family Aplysiidae, order Aplysiida, found in the northeastern Atlantic Ocean and Mediterranean Sea, with confirmed records from Denmark, Norway, Portugal, and Sweden. This species typically inhabits shallow subtidal and intertidal zones with abundant macroalgae, feeding primarily on red and green algae — a diet that influences the color of the defensive purple ink it secretes when threatened. <em>Aplysia punctata</em> is a simultaneous hermaphrodite, capable of acting as both male and female during mating, and often forms mating chains involving multiple individuals. It can reach considerable size among European opisthobranch species, though body dimensions vary considerably with age and feeding conditions. The species is classified as Least Concern by the IUCN, reflecting stable populations across its coastal range. Biological traits for this species remain poorly documented in the scientific literature, including precise average data on lifespan, body length, weight, and detailed seasonal dietary patterns, though its general herbivorous feeding on macroalgae is well established.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden