Common Yellow Conch vs Rootless Duckweed

Agapeta hamana compared with Wolffia arrhiza

Key Differences

• Common Yellow Conch is Least Concern while Rootless Duckweed is Endangered.

Taxonomic Classification

Rank	Common Yellow Conch	Rootless Duckweed
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Liliopsida (Monocots)
Order	Lepidoptera (Butterflies & Moths)	Alismatales (Alismatales)
Family	Tortricidae	Araceae
Genus	Agapeta	Wolffia
Species	Agapeta hamana	Wolffia arrhiza

Conservation Status

Common Yellow Conch

LC — Least Concern

Rootless Duckweed

EN — Endangered

Physical Characteristics

Attribute	Common Yellow Conch	Rootless Duckweed
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Yellow Conch

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Rootless Duckweed

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, temperate broadleaf and mixed forests, and temperate coniferous forests, among 4 distinct biome types spanning the Indomalayan and Oceanian and Palearctic realms. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Japan), Europe (10 countries), North America (Canada), and South America (Brazil). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Yellow Conch

<em>Agapeta hamana</em>, the common yellow conch moth, is a small moth in the family Tortricidae. It is widely distributed across Europe and central Asia, ranging from Britain and Scandinavia eastward through much of the Palearctic region. The species inhabits dry grasslands, heathlands, chalk downlands, and scrubby habitats where its larval host plants are found. Adult moths display distinctive pale yellow to golden-yellow forewings with irregular brown or reddish-brown markings near the wingtip, forming a pattern that resembles the shell of a conch, lending the species its common name. The wingspan typically measures around 15–22 mm. Biological traits such as average adult lifespan, precise body weight, and detailed population data remain poorly documented in consolidated scientific literature. Larvae feed internally on the roots of thistles and knapweeds, particularly <em>Centaurea</em> and <em>Cirsium</em> species. Adults fly from June to August and are frequently attracted to light. <em>Agapeta hamana</em> has been investigated as a potential biological control agent for invasive knapweed species in North America, where it has been introduced experimentally. The species is assessed as Least Concern given its broad distribution and stable habitat associations.

Shared Countries

Both species can be found in 3 countries:

🇧🇪 Belgium 🇳🇴 Norway 🇸🇪 Sweden