coast amaranth vs Common Duckweed

Amaranthus pumilus compared with Lemna minor

Key Differences

• coast amaranth is Extinct while Common Duckweed is Least Concern.

Taxonomic Classification

Rank	coast amaranth	Common Duckweed
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Magnoliopsida (Dicots)	Liliopsida (Monocots)
Order	Caryophyllales (Caryophyllales)	Alismatales (Alismatales)
Family	Amaranthaceae	Araceae
Genus	Amaranthus	Lemna
Species	Amaranthus pumilus	Lemna minor

Evolutionary Relationship

coast amaranth and Common Duckweed share a common ancestor at the Phylum level: Magnoliophyta. (Flowering Plants)

Conservation Status

coast amaranth

EX — Extinct

Common Duckweed

LC — Least Concern

Physical Characteristics

Attribute	coast amaranth	Common Duckweed
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

coast amaranth

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Found in Japan.

Common Duckweed

Habitat

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

Range

Widely distributed across Europe (8 countries), North America (Canada, United States), Oceania and the Pacific (Australia), and South America (Brazil, Guyana).

coast amaranth

Coast amaranth (Amaranthus pumilus) is an annual herb in the family Amaranthaceae, native to the Atlantic and Gulf coasts of the eastern United States, where it once grew on coastal foredunes, beach strand, and shell-hash substrates above the high tide line from New York south to South Carolina. It is a low-growing, fleshy plant with small, rounded leaves and inconspicuous green flowers typical of the genus. Coast amaranth is assessed as Extinct in the Wild by the IUCN, as it has not been reliably documented from wild populations since the mid-20th century; the last confirmed collections date to the 1960s. The species' decline and likely extinction resulted from intense human pressure on Atlantic coastal habitats through shoreline development, beach stabilisation, vehicular traffic on beaches, and increased storm frequency disrupting pioneer dune vegetation. It is federally listed as Threatened in the United States, though this listing predates confirmed extinction in the wild. A small number of ex-situ accessions may exist in botanical garden collections. Genetic material and seed banking efforts represent the only remaining conservation options for this critically reduced species.

Common Duckweed

<em>Lemna minor</em>, commonly known as common duckweed, is a tiny floating aquatic plant in the family Araceae, recognized as one of the smallest flowering plants on Earth. Classified as Least Concern by the IUCN, the species enjoys a broad distribution across Europe, North America, Oceania, and South America, colonizing a diverse array of habitats including grasslands, wetlands, forests, and cultivated land with access to standing or slow-moving water. It typically inhabits ponds, lakes, ditches, and quiet streams, forming extensive green mats on the water surface. <em>Lemna minor</em> reproduces predominantly through asexual budding, allowing populations to expand rapidly under favorable conditions. The species provides vital ecosystem services, stabilizing nutrient cycles, reducing algal blooms through competition, and offering food and shelter for aquatic invertebrates, fish, and waterfowl. Due to its sensitivity to water quality, it is frequently used as a bioindicator in ecotoxicological research. Common duckweed has also attracted scientific interest for its potential in wastewater treatment and as a high-protein animal feed supplement. Biological traits of this species remain poorly documented in the scientific literature.