vs Coastal Ragweed

Chroococcus planctonicus compared with Ambrosia hispida

Key Differences

• is Not Evaluated while Coastal Ragweed is Least Concern.

Taxonomic Classification

Rank		Coastal Ragweed
Kingdom	Bacteria (Bacteria)	Plantae (Plants)
Phylum	Cyanobacteria (Cyanobacteria)	Magnoliophyta (Flowering Plants)
Class	Cyanobacteriia	Magnoliopsida (Dicots)
Order	Cyanobacteriales	Asterales (Daisies & Sunflowers)
Family	Microcystaceae	Asteraceae (Daisy Family)
Genus	Chroococcus	Ambrosia
Species	Chroococcus planctonicus	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 Norway and Sweden.

Coastal Ragweed

Habitat

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

Range

Found in Cuba.

Chroococcus planctonicus is a species of cyanobacteria in the family Chroococcaceae, adapted to the planktonic lifestyle suggested by its specific epithet. Unlike some Chroococcus species that are primarily benthic or periphytic — attached to substrates — Chroococcus planctonicus is characteristic of open-water plankton communities in freshwater lakes and ponds. Planktonic cyanobacteria must maintain a position in the water column for optimal light exposure, and some have evolved gas vesicles to regulate buoyancy, though these are more developed in filamentous bloom-forming genera. Chroococcus planctonicus cells are spherical, occurring in pairs or tetrads within gelatinous sheaths, following the basic morphological plan of the genus. It has been documented from European freshwater systems including Swedish and Finnish lakes, where it contributes to the seasonal phytoplankton community. Cyanobacteria are important primary producers in freshwater ecosystems, particularly in summer when warm temperatures and stratified water columns favor their growth. However, Chroococcus planctonicus is not generally associated with harmful algal blooms, which are more characteristic of genera such as Microcystis and Anabaena. Its conservation status has not been assessed.

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.