common freshwater nerite vs Epaulard

Theodoxus fluviatilis compared with Orcinus orca

Key Differences

• common freshwater nerite is Least Concern while Epaulard is Data Deficient.

Taxonomic Classification

Rank	common freshwater nerite	Epaulard
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (Mollusks)	Chordata (Chordates)
Class	Gastropoda (Gastropoda)	Mammalia (Mammals)
Order	Cycloneritida (Cycloneritida)	Cetacea (Whales & Dolphins)
Family	Neritidae	Delphinidae (Oceanic Dolphins)
Genus	Theodoxus	Orcinus (Orcas)
Species	Theodoxus fluviatilis	Orcinus orca

Evolutionary Relationship

common freshwater nerite and Epaulard share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

common freshwater nerite

LC — Least Concern

Epaulard

DD — Data Deficient

Population: ~50.0K

Trend: Unknown ?

Physical Characteristics

Attribute	common freshwater nerite	Epaulard
Diet	—	Carnivore
Average Lifespan	—	50 years
Average Length	—	8.0 m
Average Weight	—	5.4 t

Habitat & Geographic Range

common freshwater nerite

Habitat

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

Range

Found across Europe (11 countries).

Epaulard

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, Venezuela).

common freshwater nerite

<em>Theodoxus fluviatilis</em>, commonly known as the common freshwater nerite, is a small aquatic gastropod mollusc belonging to the family Neritidae. This species is widely distributed across Europe, with documented occurrences in Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Hungary, Latvia, Norway, and Sweden. It typically inhabits freshwater environments, including rivers, streams, and lakes, where it grazes on algae and biofilm on hard substrates such as rocks and submerged wood. The common freshwater nerite is assessed as Least Concern on conservation metrics, reflecting its broad distribution and relatively stable populations across much of its European range. Biological traits of this species remain poorly documented in the scientific literature. <em>Theodoxus fluviatilis</em> plays an ecological role as a grazer in freshwater benthic communities, contributing to the regulation of algal growth on hard surfaces. The species typically favors clean, well-oxygenated waters and can serve as an indicator of water quality in freshwater systems. Its distinctive small, dome-shaped shell with variable patterning makes it recognizable among freshwater invertebrates.

Epaulard

The largest member of the dolphin family, orcas reach up to 9 meters and 6 tonnes and are found in every ocean from Arctic to Antarctic. Apex predators living in matrilineal pods with distinct dialects, hunting strategies, and cultural traditions that differ between populations. Some populations specialize in fish, others in marine mammals. No natural predators; orcas sit at the top of every marine food chain they inhabit.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden