vs Polar bear

Chrysococcus cystophorus compared with Ursus maritimus

Key Differences

is Not Evaluated while Polar bear is Vulnerable.

Taxonomic Classification

Rank		Polar bear
Kingdom	Chromista (クロミスタ)	Animalia (動物)
Phylum	Ochrophyta (オクロ植物)	Chordata (脊索動物)
Class	Chrysophyceae (黄金色藻)	Mammalia (哺乳類)
Order	Chromulinales (Chromulinales)	Carnivora (ネコ目)
Family	Dinobryaceae	Ursidae (Bears)
Genus	Chrysococcus	Ursus (Bears)
Species	Chrysococcus cystophorus	Ursus maritimus

Conservation Status

NE — Not Evaluated

Polar bear

VU — Vulnerable

Population: ~26.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute		Polar bear
Diet	—	Carnivore
Average Lifespan	—	25 years
Average Length	—	2.4 m
Average Weight	—	450.0 kg

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Polar bear

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and boreal forests and taiga, among 4 distinct biome types within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Found in Norway. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Chrysococcus cystophorus is a unicellular freshwater chrysophyte microalga in the genus Chrysococcus, family Chromulinaceae, class Chrysophyceae. The specific epithet cystophorus, meaning cyst-bearing, references this species' relationship with siliceous cyst formation — a shared feature across many chrysophytes that produce species-specific resting stages called stomatocysts or statospores. In chrysophytes, the stomatocyst is a silicified internal cyst with a characteristic plug-sealed pore, and its morphology is often used as an additional taxonomic character in species identification. C. cystophorus inhabits freshwater environments and has been recorded from Norwegian waters along with other Scandinavian localities, fitting the pattern of chrysophyte species diversity documented through freshwater surveys in the region. Chrysococcus cells are enclosed within a lorica — a proteinaceous or organic outer vessel — from which flagella emerge for locomotion. The lorica shape and ornamentation, along with the dimensions and flagellar arrangement, are primary characters used for species identification. Like other chrysophytes, C. cystophorus is golden-brown in color owing to chlorophylls a and c together with fucoxanthin pigments in the chloroplast. Chrysococcus species function as primary producers in freshwater plankton communities, particularly in oligotrophic lakes where smaller algae outcompete larger taxa. C. cystophorus has not been evaluated under IUCN Red List criteria and is listed as Not Evaluated, consistent with the general status of freshwater microalgal taxa.

Polar bear

地球上で最大の陸上肉食動物であるホッキョクグマは700kgを超えることがあり、カナダからロシアまでの北極海氷域全体に分布する。ワモンアザラシとヒゲアザラシを狩るために海氷に依存する高度に特化した海洋哺乳類である。広大な距離を泳ぐことができる優れた泳者でもある。脆弱種に指定されており、気候変動による急激な北極海氷の消失で個体群が深刻な圧力を受けている。