Caspian Knotweed vs Castor

Polygonum caspicum compared with Ricinus communis

Key Differences

• Caspian Knotweed is Critically Endangered while Castor is Not Evaluated.

Taxonomic Classification

Rank	Caspian Knotweed	Castor
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order	Caryophyllales (Caryophyllales)	Malpighiales (Malpighiales)
Family	Polygonaceae	Euphorbiaceae
Genus	Polygonum	Ricinus
Species	Polygonum caspicum	Ricinus communis

Evolutionary Relationship

Caspian Knotweed and Castor share a common ancestor at the Class level: Magnoliopsida. (Dicots)

Conservation Status

Caspian Knotweed

CR — Critically Endangered

Castor

NE — Not Evaluated

Physical Characteristics

Attribute	Caspian Knotweed	Castor
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Caspian Knotweed

Habitat

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

Castor

Habitat

Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 7 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (33 countries), Asia (26 countries), Europe (23 countries), North America (15 countries), Oceania and the Pacific (14 countries), and South America (12 countries).

Caspian Knotweed

The Caspian Knotweed (Polygonum caspicum) is a species in the genus Polygonum. It is currently classified as Critically Endangered on the IUCN Red List. Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Castor

The Castor (Ricinus communis) is a species in the genus Ricinus. Found across multiple habitat types including tropical and subtropical dry broadleaf forests, flooded grasslands and savannas, and montane grasslands and shrublands, among 7 distinct biome types. Populations are also found in montane and hi