Brittle Naiad vs Common Water-Nymph

Najas minor compared with Najas guadalupensis

Key Differences

• Brittle Naiad is Critically Endangered while Common Water-Nymph is Not Evaluated.

Taxonomic Classification

Rank	Brittle Naiad	Common Water-Nymph
Kingdom same	Plantae (植物)	Plantae (植物)
Phylum same	Magnoliophyta (被子植物門)	Magnoliophyta (被子植物門)
Class same	Liliopsida (単子葉植物綱)	Liliopsida (単子葉植物綱)
Order same	Alismatales (オモダカ目)	Alismatales (オモダカ目)
Family same	Hydrocharitaceae	Hydrocharitaceae
Genus same	Najas	Najas
Species	Najas minor	Najas guadalupensis

Evolutionary Relationship

Brittle Naiad and Common Water-Nymph share a common ancestor at the Genus level: Najas.

Conservation Status

Brittle Naiad

CR — Critically Endangered

Common Water-Nymph

NE — Not Evaluated

Physical Characteristics

Attribute	Brittle Naiad	Common Water-Nymph
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brittle Naiad

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical coniferous forests, and temperate broadleaf and mixed forests, among 9 distinct biome types spanning the Indomalayan and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Pakistan, Taiwan), Europe (4 countries), and North America (Canada, United States). Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Water-Nymph

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Widely distributed across Asia (Israel, Taiwan), Europe (4 countries), North America (4 countries), and South America (Brazil, Colombia).

Brittle Naiad

The Brittle Naiad (Najas minor) is a species in the genus Najas. It is currently classified as Critically Endangered on the IUCN Red List. Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical coniferous forests, and temperate broadleaf and mixed forests, among 9 distinct biome types spanning the Indomalayan an

Common Water-Nymph

<em>Najas guadalupensis</em>, commonly known as the common water nymph or southern naiad, is a submerged aquatic plant in the family Hydrocharitaceae. Its conservation status is listed as Not Evaluated by the IUCN. The species has an extensive distribution spanning Asia, Europe, and the Americas, where it inhabits a wide range of lentic and lotic freshwater environments including ponds, lakes, slow streams, and irrigation channels. It typically grows fully submerged, rooting in sandy or muddy substrates in water ranging from shallow margins to depths exceeding two meters. The plant is slender and branching, with narrow, finely toothed leaves arranged oppositely or in whorls along the stem. <em>Najas guadalupensis</em> is adapted to a range of water quality conditions and can persist in turbid, nutrient-enriched environments where other aquatic macrophytes cannot. It typically reproduces through both seed and fragmentation, with stem fragments readily establishing new colonies. Pollination occurs underwater, with pollen dispersed directly through the water column. Biological traits including average lifespan, stem length, and mass remain poorly documented in standardized databases. Ecologically, common water nymph provides important submerged habitat structure for fish, invertebrates, and waterfowl, offering spawning substrate, foraging areas, and refuge from predators in the diverse freshwater systems it occupies throughout its broad geographic range.

Shared Countries

Both species can be found in 3 countries:

🇳🇴 Norway 🇹🇼 Taiwan 🇺🇸 United States