common freshwater nerite vs common greasewort

Theodoxus fluviatilis compared with Aneura pinguis

Taxonomic Classification

Rank	common freshwater nerite	common greasewort
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Mollusca (Mollusks)	Marchantiophyta (liverwort)
Class	Gastropoda (Gastropoda)	Jungermanniopsida (Jungermanniopsida)
Order	Cycloneritida (Cycloneritida)	Metzgeriales (Metzgeriales)
Family	Neritidae	Aneuraceae
Genus	Theodoxus	Aneura
Species	Theodoxus fluviatilis	Aneura pinguis

Conservation Status

common freshwater nerite

LC — Least Concern

common greasewort

LC — Least Concern

Physical Characteristics

Attribute	common freshwater nerite	common greasewort
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

common freshwater nerite

Habitat

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

Range

Found across Europe (11 countries).

common greasewort

Habitat

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

Range

Widely distributed across Asia (Taiwan), Europe (6 countries), North America (United States), and South America (Brazil, Colombia).

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.

common greasewort

<em>Aneura pinguis</em>, commonly known as common greasewort, is a liverwort belonging to the genus Aneura within the family Aneuraceae. This cryptogamic plant inhabits ecosystems across Asia, Europe, and North America, thriving in moist or waterlogged environments. Its range encompasses Taiwan in Asia, six European countries, the United States in North America, and Brazil and Colombia in South America, indicating a broad geographic distribution across multiple continents. Common greasewort is assessed as Least Concern on the IUCN Red List. The species typically forms flat, ribbon-like thalli in damp habitats such as stream banks, wet rocks, and boggy ground. Biological traits of this species remain poorly documented in the scientific literature.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden