blue whale vs Cimar Round Ray

Balaenoptera musculus compared with Urotrygon cimar

Key Differences

• blue whale is Vulnerable while Cimar Round Ray is Near Threatened.

Taxonomic Classification

Rank	blue whale	Cimar Round Ray
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum same	Chordata (脊索動物)	Chordata (脊索動物)
Class	Mammalia (哺乳類)	Elasmobranchii
Order	Cetacea (Whales & Dolphins)	Myliobatiformes (トビエイ目)
Family	Balaenopteridae (Rorquals)	Urotrygonidae
Genus	Balaenoptera (Rorquals)	Urotrygon
Species	Balaenoptera musculus	Urotrygon cimar

Evolutionary Relationship

blue whale and Cimar Round Ray share a common ancestor at the Phylum level: Chordata. (脊索動物)

Conservation Status

blue whale

VU — Vulnerable

Population: ~15.0K

Trend: Increasing ↑

Cimar Round Ray

NT — Near Threatened

Physical Characteristics

Attribute	blue whale	Cimar Round Ray
Diet	Carnivore	—
Average Lifespan	90 years	—
Average Length	30.0 m	—
Average Weight	150.0 t	—

Habitat & Geographic Range

blue whale

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Taiwan), Europe (4 countries), and South America (Colombia, Ecuador). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Cimar Round Ray

blue whale

地球上で生きたことが知られている最大の動物であるシロナガスクジラ（Balaenoptera musculus）は、体長33メートル、体重200トンに達することができ、心臓だけで小型自動車ほどの重さがあります。全ての海洋に生息し、極地の餌場と熱帯の繁殖地の間を回遊します。1日最大4トンのオキアミを摂取する濾過摂食者です。20世紀の捕鯨による絶滅危機からの回復後、世界的な個体数は10,000〜25,000頭と推定される絶滅危惧種です。

Cimar Round Ray

The Cimar round ray (Urotrygon cimar) is a small stingray in the family Urotrygonidae, found in the eastern Pacific Ocean along the coasts of Central America and northern South America, including the waters of Costa Rica, Panama, Colombia, and Ecuador. It inhabits shallow coastal and estuarine waters over sandy and muddy bottoms, typically at depths of less than 50 meters, where it feeds on small benthic invertebrates and fish. Like other round rays in the genus Urotrygon, it has a nearly circular disc outline, a relatively slender tail, and a venomous caudal spine used defensively against predators. The species is classified as Near Threatened by the IUCN, reflecting its restricted range, vulnerability to coastal habitat degradation, and incidental capture in artisanal and commercial fisheries throughout its range. Bycatch in shrimp trawls and gill nets represents a significant ongoing threat to Urotrygon species throughout the eastern Pacific. Shallow coastal habitats in Central America and Colombia face continued pressure from development, mangrove loss, and pollution. The species' reproductive biology, like that of most Urotrygon rays, involves ovoviviparity, with females giving birth to live young after internal development. Population assessments for this species remain limited, and more data on abundance and mortality rates are needed.