vs Laysan Duck

Chrysococcus cystophorus compared with Anas laysanensis

Key Differences

is Not Evaluated while Laysan Duck is Critically Endangered.

Taxonomic Classification

Rank		Laysan Duck
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Chordata (Chordates)
Class	Chrysophyceae (Chrysophyceae)	Aves (Birds)
Order	Chromulinales (Chromulinales)	Anseriformes (Anseriformes)
Family	Dinobryaceae	Anatidae
Genus	Chrysococcus	Anas
Species	Chrysococcus cystophorus	Anas laysanensis

Conservation Status

NE — Not Evaluated

Laysan Duck

CR — Critically Endangered

Physical Characteristics

Attribute		Laysan Duck
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Norway and Sweden.

Laysan Duck

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and Mediterranean forests and woodlands within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Belgium, France, Netherlands, Norway, and United Kingdom. Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Chrysococcus cystophorus is a unicellular freshwater chrysophyte microalga in the genus Chrysococcus, family Chromulinaceae, class Chrysophyceae. The specific epithet cystophorus, meaning cyst-bearing, references this species' relationship with siliceous cyst formation — a shared feature across many chrysophytes that produce species-specific resting stages called stomatocysts or statospores. In chrysophytes, the stomatocyst is a silicified internal cyst with a characteristic plug-sealed pore, and its morphology is often used as an additional taxonomic character in species identification. C. cystophorus inhabits freshwater environments and has been recorded from Norwegian waters along with other Scandinavian localities, fitting the pattern of chrysophyte species diversity documented through freshwater surveys in the region. Chrysococcus cells are enclosed within a lorica — a proteinaceous or organic outer vessel — from which flagella emerge for locomotion. The lorica shape and ornamentation, along with the dimensions and flagellar arrangement, are primary characters used for species identification. Like other chrysophytes, C. cystophorus is golden-brown in color owing to chlorophylls a and c together with fucoxanthin pigments in the chloroplast. Chrysococcus species function as primary producers in freshwater plankton communities, particularly in oligotrophic lakes where smaller algae outcompete larger taxa. C. cystophorus has not been evaluated under IUCN Red List criteria and is listed as Not Evaluated, consistent with the general status of freshwater microalgal taxa.

Laysan Duck

Laysan Duck (Anas laysanensis) is classified as Critically Endangered (CR) on the IUCN Red List. Facing an extremely high risk of extinction in the wild due to severe population decline and habitat loss.