Common Silver Hairgrass vs Linear Leaf Water Primrose

Aira caryophyllea compared with Ludwigia hyssopifolia

Key Differences

• Common Silver Hairgrass is Endangered while Linear Leaf Water Primrose is Least Concern.

Taxonomic Classification

Rank	Common Silver Hairgrass	Linear Leaf Water Primrose
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Liliopsida (Monocots)	Magnoliopsida (Dicots)
Order	Poales (Grasses)	Myrtales (Myrtales)
Family	Poaceae (Grass Family)	Onagraceae
Genus	Aira	Ludwigia
Species	Aira caryophyllea	Ludwigia hyssopifolia

Evolutionary Relationship

Common Silver Hairgrass and Linear Leaf Water Primrose share a common ancestor at the Phylum level: Magnoliophyta. (Flowering Plants)

Conservation Status

Common Silver Hairgrass

EN — Endangered

Linear Leaf Water Primrose

LC — Least Concern

Physical Characteristics

Attribute	Common Silver Hairgrass	Linear Leaf Water Primrose
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Silver Hairgrass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical grasslands and savannas, and flooded grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (Cameroon), Asia (Japan, South Korea), Europe (6 countries), North America (4 countries), Oceania and the Pacific (Australia), and South America (4 countries). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Linear Leaf Water Primrose

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and deserts and xeric shrublands spanning the Australasia and Indomalayan realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (Congo (DRC), Guinea, Seychelles), Asia (4 countries), North America (Guatemala, Honduras), Oceania and the Pacific (7 countries), and South America (Brazil, Colombia).

Common Silver Hairgrass

<em>Aira caryophyllea</em>, commonly known as Common Silver Hairgrass, is a slender annual grass belonging to the family Poaceae within the order Poales. This delicate grass is currently classified as Endangered on the IUCN Red List, reflecting significant conservation concern despite its historically broad distribution. It is typically found across a remarkable diversity of biome types, including tropical and subtropical moist broadleaf forests, grasslands, savannas, and flooded habitats, demonstrating notable ecological versatility. Its geographic range spans multiple continents, with documented populations in Africa (Cameroon), Asia (Japan, South Korea), Europe, North America, Australia, and South America. As an annual grass, it completes its life cycle within a single growing season, reproducing via wind-dispersed seeds. The inflorescence typically bears silvery, shimmering spikelets that give the species its common name. Biological traits such as average lifespan, body dimensions, and dietary specifics follow typical patterns for annual grasses — drawing nutrients from soil through root absorption rather than consuming other organisms. The endangered status suggests populations may be declining due to habitat loss, land-use change, or invasive species pressure across parts of its range.

Shared Countries

Both species can be found in 1 countries:

🇨🇴 Colombia