vs

Cocconeis neodiminuta compared with Cocconeis placentula

Taxonomic Classification

Rank
Kingdom same	Chromista (โครมิสตา)	Chromista (โครมิสตา)
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 neodiminuta	Cocconeis placentula

Evolutionary Relationship

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

ดู: 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 neodiminuta is a small, adnate diatom in the family Cocconeidaceae, distinguished from related species within the genus by its diminutive frustule size and specific silica wall ornamentation patterns resolvable by electron microscopy. As a member of the genus Cocconeis, this species is an epiphytic organism that lives attached to the surfaces of aquatic plants, filamentous algae, sediment particles, and submerged solid substrates in freshwater and occasionally brackish environments. The frustule—the intricate silica cell wall that encases the diatom cell—consists of two overlapping halves (valves) with species-specific striation patterns and pore fields (areolae) used in taxonomic identification. Cocconeis neodiminuta has been documented from freshwater environments across South America and various other regions, suggesting a broad cosmopolitan distribution consistent with many freshwater diatom taxa. The species, like other cocconeid diatoms, reproduces primarily by asexual binary fission, with periodic sexual reproduction through auxospore formation to restore cell size after successive divisions cause progressive size reduction. As a photosynthetic primary producer in benthic communities, this diatom contributes to the base of aquatic food webs and participates in the biological cycling of silicon—an element critical to diatom frustule production and removed from solution as diatoms proliferate. Its conservation status has not been evaluated by the IUCN.

Cocconeis placentula is among the most ubiquitous and widely studied freshwater and brackish-water diatoms worldwide, serving as a model organism for periphyton ecology and a key species in biological assessment of water quality. A member of the family Cocconeidaceae, this adnate epiphyte produces a characteristic ovoid frustule with fine transapical striae, a well-developed raphe system on one valve, and an elaborate pattern of areolae visible under electron microscopy. The species complex encompasses several morphological varieties (var. placentula, var. lineata, var. euglypta, var. acuta) that differ in fine structural details of the valve ornamentation. Cocconeis placentula colonizes the surfaces of aquatic plants, algae, rocks, and sediment particles in rivers, lakes, and ponds across a vast global range spanning Europe, the Americas, Asia, Africa, and beyond, tolerating a wide range of water temperatures, pH values, and moderate nutrient enrichment. Its abundance varies dramatically with substrate type, light availability, and water chemistry, making community composition data involving this species valuable in diatom-based paleolimnological reconstructions and modern bioassessment indices. As a benthic primary producer, C. placentula contributes substantially to the productivity of the photic benthos and serves as a dietary component for invertebrate grazers. Its remarkable cosmopolitan distribution and ecological flexibility make it one of the defining species of freshwater periphyton communities globally. Conservation status is not formally assessed.