vs Polar bear

Chrysochromulina cyathophora 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	Haptophyta (ハプト藻)	Chordata (脊索動物)
Class	Prymnesiophyceae (Prymnesiophyceae)	Mammalia (哺乳類)
Order	Prymnesiales (Prymnesiales)	Carnivora (ネコ目)
Family	Chrysochromulinaceae	Ursidae (Bears)
Genus	Chrysochromulina	Ursus (Bears)
Species	Chrysochromulina cyathophora	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.

Chrysochromulina cyathophora is a unicellular marine haptophyte in the genus Chrysochromulina, order Prymnesiales, class Prymnesiophyceae. The specific epithet cyathophora derives from Greek meaning cup-bearing, describing a characteristic cup-shaped element — likely a scale morphology — visible under transmission electron microscopy. Such ultrastructural features are essential for species identification within Chrysochromulina, where species are otherwise morphologically similar at the light microscopy level. C. cyathophora is known from Norwegian coastal marine environments and has also been recorded from Brazilian waters, a distribution pattern shared by several Chrysochromulina species, suggesting either broad Atlantic dispersal or recurrent misidentification across these distant populations. The species occupies the nanoplankton size fraction and is adapted to life in the water column of coastal to open-ocean marine systems. Chrysochromulina species as a group are important contributors to marine primary production, particularly in oligotrophic environments where smaller phytoplankton dominate. They may also practice mixotrophy — ingesting bacteria and small prey alongside photosynthesis — providing metabolic flexibility in nutrient-limited conditions. The life cycle of Chrysochromulina typically involves asexual division, though sexual stages are poorly documented for most species. C. cyathophora has not been assessed under the IUCN Red List framework, carrying a conservation status of Not Evaluated, consistent with the broader treatment of marine microplankton taxa that present significant challenges for population-level assessment and threat evaluation.

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。