vs small tortoiseshell

Cocconeis disculus compared with Aglais urticae

Key Differences

is Not Evaluated while small tortoiseshell is Near Threatened.

Taxonomic Classification

Rank		small tortoiseshell
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Arthropoda (Arthropods)
Class	Bacillariophyceae (Bacillariophyceae)	Insecta (Insects)
Order	Achnanthales (Achnanthales)	Lepidoptera (Butterflies & Moths)
Family	Cocconeidaceae	Nymphalidae (Brush-footed Butterflies)
Genus	Cocconeis	Aglais
Species	Cocconeis disculus	Aglais urticae

Conservation Status

NE — Not Evaluated

small tortoiseshell

NT — Near Threatened

Physical Characteristics

Attribute		small tortoiseshell
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.

small tortoiseshell

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Found across Europe (41 countries). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

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.

small tortoiseshell

small tortoiseshell (Aglais urticae) is classified as Near Threatened (NT) on the IUCN Red List. Close to qualifying as threatened, with populations that may become vulnerable without conservation action.