vs Laysan Duck

Chrysococcus bisetus 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 bisetus	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 bisetus is a species of unicellular chrysophyte microalga in the genus Chrysococcus, class Chrysophyceae, order Chromulinales. The genus Chrysococcus is characterized by cells enclosed within a lorica — a secreted outer case or vesicle — through which flagella protrude, a structure that distinguishes it from many other chrysophytes. The epithet bisetus, meaning two-bristled, describes a diagnostic feature of the lorica, which bears two bristle-like projections used for species identification. Chrysococcus species inhabit freshwater and brackish environments, typically occurring in cool, nutrient-poor to moderately enriched lakes, ponds, and slow-flowing water bodies. C. bisetus has been recorded from Norwegian and Swedish waters, consistent with the historical focus of chrysophyte research in Scandinavian freshwater habitats, and also from Brazilian waters, suggesting a broader distribution. Chrysophytes including Chrysococcus species are important components of oligotrophic lake phytoplankton, where they contribute to primary production and serve as food for zooplankton. The golden-brown coloration of Chrysococcus arises from chlorophylls a and c together with fucoxanthin, pigments shared with other heterokonts. Unlike diatoms, chrysophytes produce chrysolaminarin as their storage carbohydrate rather than starch. C. bisetus has not been assessed under IUCN criteria and is listed as Not Evaluated. As with most freshwater microalgae, global population size and distribution are poorly characterized, limiting meaningful conservation assessment.

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.