vs

Cocconeis disculus compared with Cocconeis scutellum

Taxonomic Classification

Rank
Kingdom same	Chromista (Chromista)	Chromista (Chromista)
Phylum same	Ochrophyta (Ochrophyta)	Ochrophyta (Ochrophyta)
Class same	Bacillariophyceae (Bacillariophyceae)	Bacillariophyceae (Bacillariophyceae)
Order same	Achnanthales (Achnanthales)	Achnanthales (Achnanthales)
Family same	Cocconeidaceae	Cocconeidaceae
Genus same	Cocconeis	Cocconeis
Species	Cocconeis disculus	Cocconeis scutellum

Evolutionary Relationship

and share a common ancestor at the Genus level: Cocconeis.

Lihat Genus: Cocconeis

Conservation Status

NE — Not Evaluated

Physical Characteristics

Attribute
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

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

Range

Distributed across Brazil, Norway, and Sweden.

Habitat

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

Range

Distributed across Brazil, Norway, Portugal, Sweden, and Taiwan.

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.

Cocconeis scutellum is a marine and brackish-water diatom in the family Cocconeidaceae, one of the most commonly encountered epiphytic diatoms in coastal ecosystems worldwide. The frustule is broadly oval and relatively large for the genus, with robust silica walls bearing coarse transapical striae that give the valve a distinctive, shield-like appearance—a morphology reflected in the species epithet 'scutellum,' Latin for small shield. This species is a strict epiphyte in marine environments, attaching to the surfaces of seagrasses, macroalgae such as Ulva and Zostera, coralline algae, and other benthic substrates in shallow intertidal and subtidal zones. Cocconeis scutellum has been documented from coastal habitats across the Atlantic, Pacific, and Indian Oceans, with records from temperate and tropical regions including South America, Europe, and the Indo-Pacific, reflecting its cosmopolitan marine distribution. The species is a basal component of coastal food webs: dense epiphytic biofilms including C. scutellum are grazed by amphipods, gastropods, sea urchins, and small fish, transferring photosynthetically fixed carbon up the food chain. In estuarine environments where freshwater and saltwater mix, C. scutellum may co-occur with freshwater and brackish Cocconeis species, and salinity tolerance experiments indicate the species survives across a broad range of salinities. Its silicon frustules contribute to coastal sediment biosilica content upon cell death. Conservation status is not formally evaluated.