Andersson's arctic moss vs common river snail

Arctoa anderssonii compared with Viviparus viviparus

Key Differences

Andersson's arctic moss is Endangered while common river snail is Least Concern.

Taxonomic Classification

Rank	Andersson's arctic moss	common river snail
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Bryophyta	Mollusca (Mollusks)
Class	Bryopsida (Bryopsida)	Gastropoda (Gastropoda)
Order	Dicranales (Dicranales)	Architaenioglossa (Architaenioglossa)
Family	Rhabdoweisiaceae	Viviparidae
Genus	Arctoa	Viviparus
Species	Arctoa anderssonii	Viviparus viviparus

Conservation Status

Andersson's arctic moss

EN — Endangered

common river snail

LC — Least Concern

Physical Characteristics

Attribute	Andersson's arctic moss	common river snail
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Andersson's arctic moss

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

common river snail

Habitat

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

Range

Found across Europe (7 countries).

Andersson's arctic moss

The Andersson's arctic moss (Arctoa anderssonii) is a species in the genus Arctoa. It is currently classified as Endangered on the IUCN Red List. Native to Europe, inhabiting ecosystems characteristic of the region.

common river snail

<em>Viviparus viviparus</em>, the common river snail, is a freshwater gastropod mollusk in the family Viviparidae, order Architaenioglossa. It is distributed across Europe, with populations documented in Austria, Belgium, Bulgaria, Czech Republic, France, Germany, and Hungary, among other countries, typically inhabiting slow-moving and still freshwater bodies including rivers, canals, ponds, and ditches. The species is assessed as Least Concern on the IUCN Red List. Common river snails typically live in soft-sediment benthic habitats, grazing on algae, aquatic plant material, and organic detritus using a radula — a ribbon-like feeding organ characteristic of gastropods. <em>Viviparus viviparus</em> is notable among freshwater mollusks for being viviparous, giving birth to fully formed juvenile snails rather than laying eggs, an adaptation reflected in both the genus and family names. This reproductive strategy typically results in small litter sizes but high juvenile survival compared to egg-laying mollusks. The species plays a role in benthic nutrient cycling and serves as prey for waterfowl, fish, and crayfish. Biological traits such as precise lifespan, body measurements, and population density data vary across localities and remain incompletely documented in comprehensive studies.