Colonial bentgrass vs common river snail

Agrostis capillaris compared with Viviparus viviparus

Taxonomic Classification

Rank	Colonial bentgrass	common river snail
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Mollusca (Mollusks)
Class	Liliopsida (Monocots)	Gastropoda (Gastropoda)
Order	Poales (Grasses)	Architaenioglossa (Architaenioglossa)
Family	Poaceae (Grass Family)	Viviparidae
Genus	Agrostis	Viviparus
Species	Agrostis capillaris	Viviparus viviparus

Conservation Status

Colonial bentgrass

LC — Least Concern

common river snail

LC — Least Concern

Physical Characteristics

Attribute	Colonial bentgrass	common river snail
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Colonial bentgrass

Habitat

Inhabits tropical and subtropical moist broadleaf forests within the Neotropic biogeographic realm.

Range

Widely distributed across Europe (8 countries), North America (Canada, Costa Rica, United States), Oceania and the Pacific (Australia, New Zealand), and South America (5 countries).

common river snail

Habitat

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

Range

Found across Europe (7 countries).

Colonial bentgrass

<em>Agrostis capillaris</em>, colonial bentgrass, is a perennial grass in the family Poaceae with an extensive native range across Europe and naturalised populations in North America, South America, and Oceania, including Australia and New Zealand. This species is highly adaptable, colonising tropical and subtropical moist broadleaf forests, temperate grasslands, disturbed soils, roadsides, and cultivated landscapes within the Neotropical realm. It is assessed as Least Concern by the IUCN. Colonial bentgrass is a fine-leaved, low-growing species often used in lawn and sports turf applications due to its tolerance for close mowing and its capacity to form dense, even swards. Its panicle inflorescences bear numerous small spikelets on delicate, hair-like branches, giving the species a feathery appearance when in flower. In its naturalised range, <em>Agrostis capillaris</em> can become invasive, competing with native grass species in acid grasslands and open heathlands. The species tolerates acidic and nutrient-poor soils, attributes that contribute to its widespread persistence in degraded landscapes. Biological traits of this species remain poorly documented in the scientific literature.

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.

Shared Countries

Both species can be found in 4 countries:

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