common freshwater nerite vs Komodo Dragon

Theodoxus fluviatilis compared with Varanus komodoensis

Key Differences

common freshwater nerite is Least Concern while Komodo Dragon is Endangered.

Taxonomic Classification

Rank	common freshwater nerite	Komodo Dragon
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Mollusca (Mollusks)	Chordata (Chordates)
Class	Gastropoda (Gastropoda)	Reptilia (Reptiles)
Order	Cycloneritida (Cycloneritida)	Squamata (Lizards & Snakes)
Family	Neritidae	Varanidae (Monitor Lizards)
Genus	Theodoxus	Varanus (Monitor Lizards)
Species	Theodoxus fluviatilis	Varanus komodoensis

Evolutionary Relationship

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

View Kingdom: Animalia

Conservation Status

common freshwater nerite

LC — Least Concern

Komodo Dragon

EN — Endangered

Population: ~3.5K

Trend: Stable →

Physical Characteristics

Attribute	common freshwater nerite	Komodo Dragon
Diet	—	Carnivore
Average Lifespan	—	30 years
Average Length	—	2.6 m
Average Weight	—	70.0 kg

Habitat & Geographic Range

common freshwater nerite

Habitat

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

Range

Found across Europe (11 countries).

Komodo Dragon

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 4 distinct biome types spanning the Australasia and Indomalayan realms. Populations are also found in montane and highland environments at higher elevations.

Range

Found in Indonesia. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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.