vs Coastal Ragweed

Chrysosphaerella brevispina compared with Ambrosia hispida

Key Differences

• is Not Evaluated while Coastal Ragweed is Least Concern.

Taxonomic Classification

Rank		Coastal Ragweed
Kingdom	Chromista (Chromista)	Plantae (Plants)
Phylum	Ochrophyta (Ochrophyta)	Magnoliophyta (Flowering Plants)
Class	Chrysophyceae (Chrysophyceae)	Magnoliopsida (Dicots)
Order	Ochromonadales (Ochromonadales)	Asterales (Daisies & Sunflowers)
Family	Paraphysomonadaceae	Asteraceae (Daisy Family)
Genus	Chrysosphaerella	Ambrosia
Species	Chrysosphaerella brevispina	Ambrosia hispida

Conservation Status

NE — Not Evaluated

Coastal Ragweed

LC — Least Concern

Physical Characteristics

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

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

Coastal Ragweed

Habitat

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

Range

Found in Cuba.

Chrysosphaerella brevispina is a colonial chrysophyte alga in the genus Chrysosphaerella, class Chrysophyceae. The genus is defined by its colonial organization: cells are arranged in spherical or discoid colonies in which each cell bears siliceous scales on its surface and projects stiff, spine-like silica bristles outward. The specific epithet brevispina (Latin: short spine) describes the relatively short silica spines that distinguish this species from congeners bearing longer projections. C. brevispina is found in freshwater environments, particularly in oligotrophic lakes and ponds of Scandinavia, where chrysophyte communities are richest. Chrysosphaerella species, like other chrysophytes, thrive in cold, clear, soft-water habitats and are sensitive indicators of water quality. The silica spines and scales produced by Chrysosphaerella cells are preserved in lake sediments as microfossils, providing paleoenvironmental records stretching back thousands of years. The spines may function as anti-grazing structures, reducing ingestion by zooplankton. The species has not been evaluated for conservation status by the IUCN and is listed as Not Evaluated. Its ecology and distribution in lakes outside Scandinavia are incompletely documented.

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.