Brook Floater vs Commerson s Dolphin

Alasmidonta varicosa compared with Cephalorhynchus commersonii

Key Differences

• Brook Floater is Vulnerable while Commerson s Dolphin is Least Concern.

Taxonomic Classification

Rank	Brook Floater	Commerson s Dolphin
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (Mollusks)	Chordata (Chordates)
Class	Bivalvia (Bivalvia)	Mammalia (Mammals)
Order	Unionida (Unionida)	Cetacea (Whales & Dolphins)
Family	Unionidae	Delphinidae (Oceanic Dolphins)
Genus	Alasmidonta	Cephalorhynchus
Species	Alasmidonta varicosa	Cephalorhynchus commersonii

Evolutionary Relationship

Brook Floater and Commerson s Dolphin share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Brook Floater

VU — Vulnerable

Commerson s Dolphin

LC — Least Concern

Physical Characteristics

Attribute	Brook Floater	Commerson s Dolphin
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brook Floater

Habitat

Native to North America, inhabiting ecosystems characteristic of the region.

Range

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

Commerson s Dolphin

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Brook Floater

The Brook Floater (Alasmidonta varicosa) is a species in the genus Alasmidonta. It is currently classified as Vulnerable on the IUCN Red List. Native to North America, inhabiting ecosystems characteristic of the region.

Commerson s Dolphin

<em>Cephalorhynchus commersonii</em>, commonly known as Commerson's Dolphin, is a small cetacean in the family Delphinidae. This species is classified as Least Concern on the IUCN Red List and is notable for its striking black-and-white coloration, which makes it one of the most visually distinctive dolphin species. Commerson's Dolphins typically inhabit coastal and nearshore marine environments of the Southern Hemisphere, particularly around the Falkland Islands, the southern tip of South America, and a geographically isolated population near the Kerguelen Islands in the Indian Ocean. These dolphins are highly social animals, often observed in small groups engaging in acrobatic behaviors near the surface. They typically feed on fish, squid, and crustaceans, often hunting cooperatively in shallow waters and kelp beds. Their average lifespan is approximately 18 years, and they are known for their fast, energetic swimming. Commerson's Dolphins are sometimes caught as bycatch in fishing nets, posing a localized conservation concern despite their overall Least Concern status.