coast amaranth vs Coast Sandbur

Amaranthus pumilus compared with Cenchrus spinifex

Key Differences

• coast amaranth is Extinct while Coast Sandbur is Not Evaluated.

Taxonomic Classification

Rank	coast amaranth	Coast Sandbur
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Magnoliopsida (Dicots)	Liliopsida (Monocots)
Order	Caryophyllales (Caryophyllales)	Poales (Grasses)
Family	Amaranthaceae	Poaceae (Grass Family)
Genus	Amaranthus	Cenchrus
Species	Amaranthus pumilus	Cenchrus spinifex

Evolutionary Relationship

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

Conservation Status

coast amaranth

EX — Extinct

Coast Sandbur

NE — Not Evaluated

Physical Characteristics

Attribute	coast amaranth	Coast Sandbur
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.

Coast Sandbur

Habitat

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

Range

Widely distributed across Africa (Libya, South Africa), Asia (Turkey), Europe (Greece, Norway, Romania), North America (United States), and South America (Brazil, Colombia).

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.

Coast Sandbur

Coast sandbur (Cenchrus spinifex) is an annual or short-lived perennial grass in the family Poaceae, native to warm coastal regions of the Americas but now widespread as a weed throughout tropical and subtropical regions worldwide, including Africa, Australia, and parts of Asia. It grows on coastal dunes, sandy beaches, roadsides, disturbed ground, and the margins of agricultural land. The genus Cenchrus is notable for producing sharp, bur-like seed clusters enclosed in rigid, spine-tipped involucres that readily attach to animal fur, clothing, and footwear for dispersal—a highly effective mechanism for long-distance spread. Coast sandbur is considered a nuisance weed in recreational and agricultural settings due to its painful burs. It is tolerant of salt, drought, and nutrient-poor substrates, making it a successful coloniser of disturbed coastal environments. The IUCN conservation status is Not Evaluated. While not threatened in any way, coast sandbur presents challenges in areas where it has naturalised, competing with native beach and dune vegetation.