Brook Floater vs common sea hare

Alasmidonta varicosa compared with Aplysia punctata

Key Differences

• Brook Floater is Vulnerable while common sea hare is Least Concern.

Taxonomic Classification

Rank	Brook Floater	common sea hare
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Mollusca (Mollusks)	Mollusca (Mollusks)
Class	Bivalvia (Bivalvia)	Gastropoda (Gastropoda)
Order	Unionida (Unionida)	Aplysiida (Aplysiida)
Family	Unionidae	Aplysiidae
Genus	Alasmidonta	Aplysia
Species	Alasmidonta varicosa	Aplysia punctata

Evolutionary Relationship

Brook Floater and common sea hare share a common ancestor at the Phylum level: Mollusca. (Mollusks)

Conservation Status

Brook Floater

VU — Vulnerable

common sea hare

LC — Least Concern

Physical Characteristics

Attribute	Brook Floater	common sea hare
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.

common sea hare

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

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.

common sea hare

<em>Aplysia punctata</em>, the common sea hare, is a large opisthobranch sea slug in the family Aplysiidae, order Aplysiida, found in the northeastern Atlantic Ocean and Mediterranean Sea, with confirmed records from Denmark, Norway, Portugal, and Sweden. This species typically inhabits shallow subtidal and intertidal zones with abundant macroalgae, feeding primarily on red and green algae — a diet that influences the color of the defensive purple ink it secretes when threatened. <em>Aplysia punctata</em> is a simultaneous hermaphrodite, capable of acting as both male and female during mating, and often forms mating chains involving multiple individuals. It can reach considerable size among European opisthobranch species, though body dimensions vary considerably with age and feeding conditions. The species is classified as Least Concern by the IUCN, reflecting stable populations across its coastal range. Biological traits for this species remain poorly documented in the scientific literature, including precise average data on lifespan, body length, weight, and detailed seasonal dietary patterns, though its general herbivorous feeding on macroalgae is well established.