vs Oriental House Rat

Chrysosphaerella annulata compared with Rattus tanezumi

Key Differences

• is Not Evaluated while Oriental House Rat is Least Concern.

Taxonomic Classification

Rank		Oriental House Rat
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Chordata (Chordates)
Class	Chrysophyceae (Chrysophyceae)	Mammalia (Mammals)
Order	Ochromonadales (Ochromonadales)	Rodentia (Rodents)
Family	Paraphysomonadaceae	Muridae (Mice & Rats)
Genus	Chrysosphaerella	Rattus
Species	Chrysosphaerella annulata	Rattus tanezumi

Conservation Status

NE — Not Evaluated

Oriental House Rat

LC — Least Concern

Physical Characteristics

Attribute		Oriental House Rat
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.

Oriental House Rat

Habitat

Inhabits tropical and subtropical moist broadleaf forests within the Oceanian biogeographic realm.

Range

Widely distributed across Africa (Eswatini, Lesotho, South Africa), Asia (Philippines, Taiwan), and Oceania and the Pacific (Kiribati).

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.