Coastal Ragweed vs Common Drone Fly

Ambrosia hispida compared with Eristalis tenax

Taxonomic Classification

Rank	Coastal Ragweed	Common Drone Fly
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Arthropoda (Arthropods)
Class	Magnoliopsida (Dicots)	Insecta (Insects)
Order	Asterales (Daisies & Sunflowers)	Diptera (Diptera)
Family	Asteraceae (Daisy Family)	Syrphidae
Genus	Ambrosia	Eristalis
Species	Ambrosia hispida	Eristalis tenax

Conservation Status

Coastal Ragweed

LC — Least Concern

Common Drone Fly

LC — Least Concern

Physical Characteristics

Attribute	Coastal Ragweed	Common Drone Fly
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 Drone Fly

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Widely distributed across Africa (South Africa), Europe (5 countries), North America (United States), and South America (Chile).

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 Drone Fly

<em>Eristalis tenax</em>, the common drone fly, is a hoverfly in the family Syrphidae with a broad global distribution spanning Europe, Africa, North America, and South America, including records from South Africa, five European countries, the United States, and Chile. This species typically inhabits a wide variety of terrestrial and freshwater habitats, from urban gardens and agricultural landscapes to woodland edges and wetlands. The common drone fly is one of the most effective mimics of the honey bee, a resemblance that offers protection from predators. Adults are frequently observed visiting flowers to feed on nectar and pollen, making them important pollinators in many ecosystems. Larvae, known as rat-tailed maggots, are aquatic and typically develop in stagnant, organically enriched water bodies such as sewage drains, manure pools, and polluted ponds, where they breathe through an elongated, tube-like siphon. <em>Eristalis tenax</em> is assessed as Least Concern, with stable and widespread populations. It is regarded as both an ecological indicator species and a valuable contributor to pollination services.