Alpine Rock-Cress vs

Arabis alpina compared with Cocconeis disculus

Key Differences

Alpine Rock-Cress is Least Concern while is Not Evaluated.

Taxonomic Classification

Rank	Alpine Rock-Cress
Kingdom	Plantae (Plants)	Chromista (Chromista)
Phylum	Magnoliophyta (Flowering Plants)	Ochrophyta (Ochrophyta)
Class	Magnoliopsida (Dicots)	Bacillariophyceae (Bacillariophyceae)
Order	Brassicales (Brassicales)	Achnanthales (Achnanthales)
Family	Brassicaceae	Cocconeidaceae
Genus	Arabis	Cocconeis
Species	Arabis alpina	Cocconeis disculus

Conservation Status

Alpine Rock-Cress

LC — Least Concern

NE — Not Evaluated

Physical Characteristics

Attribute	Alpine Rock-Cress
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).

Habitat

Native to Europe and South America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Brazil, Norway, and Sweden.

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).

Cocconeis disculus is a freshwater and brackish-water diatom in the family Cocconeidaceae, belonging to the class Bacillariophyceae—the diatoms, a group of unicellular photosynthetic algae encased in ornate silica cell walls called frustules. Like all members of the genus Cocconeis, C. disculus is an adnate, epiphytic species, meaning it lives attached to substrates—typically the surfaces of aquatic macrophytes, filamentous algae, and sediment particles—rather than living freely in the water column. The frustule of Cocconeis species is distinctive in its bilateral symmetry and the characteristic difference between its two valves: the rapheless valve (RV) lacks the raphe slit present on the raphe valve (RV), a feature used in species identification. Cocconeis disculus has been documented from freshwater bodies across South America and various parts of the Northern Hemisphere, with distribution reflecting its tolerance of a range of water temperatures and nutrient conditions. Diatoms like C. disculus are foundational components of aquatic food webs, fixing carbon through photosynthesis and providing a nutritious food source for grazing invertebrates, protists, and larval fish. The species also contributes to the biosilica cycle through the production and dissolution of its silica frustule. As a benthic, substrate-attached organism, Cocconeis disculus serves as a sensitive bioindicator of water quality conditions in freshwater monitoring programs. Its conservation status is not formally evaluated.