Coastal Ragweed vs Common Moonwort

Ambrosia hispida compared with Botrychium lunaria

Key Differences

• Coastal Ragweed is Least Concern while Common Moonwort is Endangered.

Taxonomic Classification

Rank	Coastal Ragweed	Common Moonwort
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum	Magnoliophyta (Flowering Plants)	Tracheophyta
Class	Magnoliopsida (Dicots)	Polypodiopsida (Polypodiopsida)
Order	Asterales (Daisies & Sunflowers)	Ophioglossales (Ophioglossales)
Family	Asteraceae (Daisy Family)	Ophioglossaceae
Genus	Ambrosia	Botrychium
Species	Ambrosia hispida	Botrychium lunaria

Evolutionary Relationship

Coastal Ragweed and Common Moonwort share a common ancestor at the Kingdom level: Plantae. (Plants)

Conservation Status

Coastal Ragweed

LC — Least Concern

Common Moonwort

EN — Endangered

Physical Characteristics

Attribute	Coastal Ragweed	Common Moonwort
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coastal Ragweed

Habitat

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

Range

Found in Cuba.

Common Moonwort

Habitat

Typically found in moist, shaded forest floors and tropical canopies.

Range

Widely distributed across Asia (Taiwan), Europe (5 countries), and North America (United States). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Coastal Ragweed

Coastal ragweed (Ambrosia hispida) is a perennial herb in the family Asteraceae, native to the coastal dunes, sandy beaches, and cays of Cuba, the Bahamas, and the wider Caribbean region. It grows in pioneer beach and dune vegetation, often forming spreading colonies that help stabilise loose coastal sands. Like other members of the genus Ambrosia, it bears inconspicuous greenish-white flowers arranged in racemes; male flower heads produce wind-dispersed pollen that can trigger allergic rhinitis in sensitive individuals. The deeply lobed, hispid leaves are adapted to reflect intense solar radiation and tolerate salt spray. Coastal ragweed plays an ecological role in early dune succession, binding sand and enabling other plant species to establish. The genus is widespread globally, with several Ambrosia species considered noxious weeds in agricultural settings, though Ambrosia hispida is restricted to its native Caribbean coastal range. The IUCN assesses it as Least Concern, reflecting adequate population size across its Caribbean coastal distribution. Pressure from coastal development and tourism infrastructure poses a localised threat to dune communities it inhabits.

Common Moonwort

Common Moonwort (<em>Botrychium lunaria</em>) is a small fern in the genus <em>Botrychium</em>, family Ophioglossaceae. It is distributed across Asia, Europe, and North America, with confirmed presence in Belgium, Denmark, Norway, Portugal, and Sweden, as well as Taiwan and the United States. The species is typically found in moist, shaded forest floors and tropical canopies. Common Moonwort is currently classified as Endangered on the IUCN Red List, indicating that it faces significant conservation challenges across its range. Its distinctive frond is divided into two parts: a sterile fan-shaped leaf portion with rounded lobes resembling a crescent moon, and a fertile spike bearing spore-bearing structures. As a fern ally rather than a flowering plant, it reproduces via spores rather than seeds. The species is associated with stable, undisturbed habitats including ancient grasslands, upland heaths, and rocky slopes. Its sensitivity to habitat disturbance and changes in land management are thought to contribute to population declines. Specific biological measurements such as lifespan and dimensions are not documented in available records.