Cliff Net-bush vs Coastal Ragweed

Melaleuca rupestris compared with Ambrosia hispida

Taxonomic Classification

Rank	Cliff Net-bush	Coastal Ragweed
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order	Myrtales (Myrtales)	Asterales (Daisies & Sunflowers)
Family	Myrtaceae	Asteraceae (Daisy Family)
Genus	Melaleuca	Ambrosia
Species	Melaleuca rupestris	Ambrosia hispida

Evolutionary Relationship

Cliff Net-bush and Coastal Ragweed share a common ancestor at the Class level: Magnoliopsida. (Dicots)

Conservation Status

Cliff Net-bush

LC — Least Concern

Coastal Ragweed

LC — Least Concern

Physical Characteristics

Attribute	Cliff Net-bush	Coastal Ragweed
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cliff Net-bush

Habitat

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

Coastal Ragweed

Habitat

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

Range

Found in Cuba.

Cliff Net-bush

Cliff Net-bush, Calothamnus rupestris, is a small shrub in the family Myrtaceae endemic to southwestern Western Australia, one of the world's recognized biodiversity hotspots. Calothamnus species, known as net-bushes or one-sided bottlebrushes, are characterized by their distinctive flower clusters arranged in a one-sided bottlebrush pattern along woody stems, with brush-like red staminal bundles typical of the genus. Cliff Net-bush grows on cliff faces, rocky slopes, and granite outcrops in the kwongan heathland of the Southwest Australian Floristic Region, tolerating the thin, nutrient-poor soils and periodic drought characteristic of these rocky substrates. The flowers provide nectar for native honeyeaters and insects. Like the majority of southwest Australian endemic plants, Cliff Net-bush is adapted to the ancient, nutrient-impoverished soils of the Gondwanan continent and the Mediterranean-type climate with hot, dry summers and mild, wet winters. Threats facing southwest Australian heathland endemics include habitat clearing for agriculture, dieback disease caused by the introduced pathogen Phytophthora cinnamomi, altered fire regimes, and climate change. The conservation status of Calothamnus rupestris requires monitoring given the overall pressure on southwest Australian flora.

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.