Big Finner vs Dwarf round ray

Balaenoptera physalus compared with Urotrygon nana

Key Differences

• Big Finner is Endangered while Dwarf round ray is Near Threatened.

Taxonomic Classification

Rank	Big Finner	Dwarf round ray
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Mammalia (Mammals)	Elasmobranchii
Order	Cetacea (Whales & Dolphins)	Myliobatiformes (Myliobatiformes)
Family	Balaenopteridae (Rorquals)	Urotrygonidae
Genus	Balaenoptera (Rorquals)	Urotrygon
Species	Balaenoptera physalus	Urotrygon nana

Evolutionary Relationship

Big Finner and Dwarf round ray share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Big Finner

EN — Endangered

Dwarf round ray

NT — Near Threatened

Physical Characteristics

Attribute	Big Finner	Dwarf round ray
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Big Finner

Habitat

Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 4 distinct biome types within the Neotropic biogeographic realm.

Range

Widely distributed across Asia (Taiwan), Europe (5 countries), and South America (Colombia, Ecuador, Venezuela). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Dwarf round ray

Big Finner

Big Finner (Balaenoptera physalus) is classified as Endangered (EN) on the IUCN Red List. At high risk of extinction in the wild, with significant population decline and ongoing threats to survival.