chocolate cosmos vs coast amaranth

Cosmos atrosanguineus compared with Amaranthus pumilus

Key Differences

• chocolate cosmos is Not Evaluated while coast amaranth is Extinct.

Taxonomic Classification

Rank	chocolate cosmos	coast amaranth
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order	Asterales (Daisies & Sunflowers)	Caryophyllales (Caryophyllales)
Family	Asteraceae (Daisy Family)	Amaranthaceae
Genus	Cosmos	Amaranthus
Species	Cosmos atrosanguineus	Amaranthus pumilus

Evolutionary Relationship

chocolate cosmos and coast amaranth share a common ancestor at the Class level: Magnoliopsida. (Dicots)

Conservation Status

chocolate cosmos

NE — Not Evaluated

coast amaranth

EX — Extinct

Physical Characteristics

Attribute	chocolate cosmos	coast amaranth
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

chocolate cosmos

Habitat

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

Range

Found in Sweden.

coast amaranth

Habitat

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

Range

Found in Japan.

chocolate cosmos

The Chocolate Cosmos (Cosmos atrosanguineus) is a herbaceous perennial in the family Asteraceae (daisy family), native to Mexico, where it is believed to be extinct in the wild. It is widely cultivated for its extraordinary deep burgundy to near-black daisy-like flower heads, which emit a distinctive vanilla-chocolate fragrance — particularly in warm weather — making it a popular and unusual ornamental plant. The genus Cosmos comprises about 40 species of flowering plants with showy composite flower heads and feathery or pinnately divided leaves. Cosmos atrosanguineus grows from tuberous roots, reaching 40–60 centimetres in height, and flowers from summer to autumn in temperate gardens. The species has not been found reproducing sexually in cultivation — all cultivated plants are believed to be sterile clones propagated vegetatively from a single introduction — raising questions about long-term genetic diversity. Despite its presumed extinction in Mexico, the species survives in cultivation worldwide, though this does not satisfy botanical criteria for in situ conservation. The IUCN lists it as Not Evaluated under current assessment protocols. The chocolate cosmos serves as an important reminder of the value of botanical gardens and horticultural collections for preserving species that have vanished from their native ranges due to agricultural conversion and other habitat pressures.

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.