Close-lobed dandelion vs Coastal Ragweed

Taraxacum densilobum compared with Ambrosia hispida

Taxonomic Classification

Rank	Close-lobed dandelion	Coastal Ragweed
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order same	Asterales (Daisies & Sunflowers)	Asterales (Daisies & Sunflowers)
Family same	Asteraceae (Daisy Family)	Asteraceae (Daisy Family)
Genus	Taraxacum	Ambrosia
Species	Taraxacum densilobum	Ambrosia hispida

Evolutionary Relationship

Close-lobed dandelion and Coastal Ragweed share a common ancestor at the Family level: Asteraceae. (Daisy Family)

Conservation Status

Close-lobed dandelion

LC — Least Concern

Coastal Ragweed

LC — Least Concern

Physical Characteristics

Attribute	Close-lobed dandelion	Coastal Ragweed
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Close-lobed dandelion

Habitat

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

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.

Close-lobed dandelion

Close-lobed dandelion refers to a microspecies within the extraordinarily diverse aggregate Taraxacum officinale sensu lato (family Asteraceae), the common dandelion complex. Dandelions are notoriously complex taxonomically due to widespread apomixis — asexual seed production without fertilization — which generates thousands of clonal microspecies that are morphologically distinguishable but reproductively isolated. Close-lobed forms are characterized by leaf lobes that are positioned closely together, with shorter spaces between the lobes than in more deeply divided or open-lobed morphs. This leaf morphology is one of dozens of characters — including lobe shape, involucre bract posture, achene color, and scape characteristics — used by Taraxacum specialists to delineate the hundreds or thousands of named microspecies. Dandelions of all morphologies are ecologically important as early-season nectar and pollen sources for bumblebees, honeybees, and numerous other pollinators. Their deep taproots break up compacted soils and bring nutrients from depth, and their seeds provide food for finches and other seed-eating birds across open habitats in temperate regions.

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.