vs

Chrysosphaerella annulata compared with Chrysosphaerella longispina

Taxonomic Classification

Rank
Kingdom same	Chromista (Chromista)	Chromista (Chromista)
Phylum same	Ochrophyta (Ochrophyta)	Ochrophyta (Ochrophyta)
Class same	Chrysophyceae (Goldbraune Algen)	Chrysophyceae (Goldbraune Algen)
Order same	Ochromonadales (Goldmonaden)	Ochromonadales (Goldmonaden)
Family same	Paraphysomonadaceae	Paraphysomonadaceae
Genus same	Chrysosphaerella	Chrysosphaerella
Species	Chrysosphaerella annulata	Chrysosphaerella longispina

Evolutionary Relationship

and share a common ancestor at the Genus level: Chrysosphaerella.

Ansehen Genus: Chrysosphaerella

Conservation Status

NE — Not Evaluated

Physical Characteristics

Attribute
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.

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across 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.

Chrysosphaerella longispina is a colonial chrysophyte alga in the genus Chrysosphaerella, notable for the long silica spines (longispina: Latin, long spine) that project from each cell in the colony. The genus is characterized by spherical or discoid colonies of photosynthetic cells that each secrete siliceous scales and elongated spine-like appendages, making Chrysosphaerella colonies distinctively bristled and visible under light microscopy. The long spines of C. longispina likely serve as anti-predation structures that make the colonies more difficult for zooplankton to ingest. C. longispina is found in cold, oligotrophic freshwater lakes, particularly in Scandinavia, where comprehensive chrysophyte surveys have documented its presence. Chrysosphaerella colonies contribute to freshwater primary production and the cycling of biogenic silica, which upon cell dissolution is deposited in lake sediments as microscopically identifiable remains. These silica structures are widely used by paleolimnologists to reconstruct past changes in lake water chemistry, thermal stratification, and climate. The conservation status of C. longispina has not been assessed by the IUCN; the species is listed as Not Evaluated.