vs common grey sea slug

Chrysosphaerella annulata compared with Aeolidia papillosa

Key Differences

is Not Evaluated while common grey sea slug is Least Concern.

Taxonomic Classification

Rank		common grey sea slug
Kingdom	Chromista (أسناخ صبغية)	Animalia (حيوانات)
Phylum	Ochrophyta (طحالب داكنة)	Mollusca (رخويات)
Class	Chrysophyceae (طحالب ذهبية)	Gastropoda (بطنيات القدم)
Order	Ochromonadales (Ochromonadales)	Nudibranchia (عاريات الخيشوم)
Family	Paraphysomonadaceae	Aeolidiidae
Genus	Chrysosphaerella	Aeolidia
Species	Chrysosphaerella annulata	Aeolidia papillosa

Conservation Status

NE — Not Evaluated

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, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

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.

Chrysosphaerella annulata is a colonial freshwater chrysophyte microalga in the genus Chrysosphaerella, class Chrysophyceae. Unlike unicellular loricate chrysophytes, Chrysosphaerella species form spherical or ellipsoidal free-floating colonies in which individual cells are embedded in a common gelatinous matrix. The individual cells bear long siliceous scales with distinctive ring-like or annular structures — referenced by the species epithet annulata — projecting outward from the colony surface, giving the colony a spiny appearance under microscopy. These siliceous scales are species-specific and their morphology, as revealed through electron microscopy, is the primary character for identifying Chrysosphaerella species. C. annulata has been recorded from Norwegian and Swedish freshwater environments, consistent with the Scandinavian emphasis in chrysophyte research and the high diversity of chrysophytes in boreal freshwater systems. Chrysosphaerella colonies are planktonic, inhabiting the limnetic zone of oligotrophic to mesotrophic lakes where they may form locally conspicuous populations during favorable conditions. The species uses chlorophylls a and c with fucoxanthin for photosynthesis, contributing to primary production. Chrysosphaerella scales can accumulate in lake sediments, providing a record of past community composition and environmental conditions. C. annulata has not been assessed under IUCN criteria and is classified as Not Evaluated. Its documentation contributes to understanding the diversity of colonial chrysophyte forms in northern European freshwater ecosystems.

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.