Alpine Rock-Cress vs Common Coontail

Arabis alpina compared with Ceratophyllum demersum

Taxonomic Classification

Rank	Alpine Rock-Cress	Common Coontail
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order	Brassicales (Brassicales)	Ceratophyllales (Ceratophyllales)
Family	Brassicaceae	Ceratophyllaceae
Genus	Arabis	Ceratophyllum
Species	Arabis alpina	Ceratophyllum demersum

Evolutionary Relationship

Alpine Rock-Cress and Common Coontail share a common ancestor at the Class level: Magnoliopsida. (Dicots)

Conservation Status

Alpine Rock-Cress

LC — Least Concern

Common Coontail

LC — Least Concern

Physical Characteristics

Attribute	Alpine Rock-Cress	Common Coontail
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Alpine Rock-Cress

Habitat

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

Range

Widely distributed across Europe (10 countries), North America (Canada, United States), and South America (Argentina).

Common Coontail

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, flooded grasslands and savannas, and deserts and xeric shrublands, among 9 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (4 countries), Asia (6 countries), Europe (8 countries), North America (4 countries), Oceania and the Pacific (4 countries), and South America (Brazil, Colombia).

Alpine Rock-Cress

The Alpine Rock-Cress (Arabis alpina) is a species in the genus Arabis. It is currently classified as Least Concern on the IUCN Red List. Typically found in diverse terrestrial habitats from tropical forests to temperate regions. Widely distributed across Europe (10 countries), North America (Canada, United States), and South America (Argentina).

Common Coontail

<em>Ceratophyllum demersum</em>, commonly known as common coontail or hornwort, is a submerged aquatic plant in the family Ceratophyllaceae. It has an almost cosmopolitan distribution, occurring on every continent except Antarctica in freshwater lakes, ponds, slow-moving rivers, and ditches. Common coontail is rootless, floating freely or loosely anchored in sediment, and forms dense underwater mats that provide important habitat and refuge for fish, invertebrates, and waterfowl. Its whorled, forked leaves are stiff and brittle with toothed margins. The species is well adapted to a wide range of water conditions and can tolerate turbid, nutrient-rich waters where other aquatic plants may struggle. It plays a significant role in aquatic ecosystems by oxygenating water and filtering excess nutrients. The species is assessed as Least Concern by the IUCN. Biological traits of this species remain poorly documented in the scientific literature.

Shared Countries

Both species can be found in 6 countries:

🇧🇪 Belgium 🇨🇦 Canada 🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden 🇺🇸 United States