vs Coastal Silver-stiletto

Chrysococcus minutus compared with Acrosathe annulata

Key Differences

is Not Evaluated while Coastal Silver-stiletto is Least Concern.

Taxonomic Classification

Rank		Coastal Silver-stiletto
Kingdom	Chromista (Chromista)	Animalia (Animals)
Phylum	Ochrophyta (Ochrophyta)	Arthropoda (Arthropods)
Class	Chrysophyceae (Chrysophyceae)	Insecta (Insects)
Order	Chromulinales (Chromulinales)	Diptera (Diptera)
Family	Dinobryaceae	Therevidae
Genus	Chrysococcus	Acrosathe
Species	Chrysococcus minutus	Acrosathe annulata

Conservation Status

NE — Not Evaluated

Coastal Silver-stiletto

LC — Least Concern

Physical Characteristics

Attribute		Coastal Silver-stiletto
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden.

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Chrysococcus minutus is a small loricate chrysophyte alga in the genus Chrysococcus, its epithet minutus (Latin: minute or very small) reflecting its diminutive cell dimensions. Like its congeners, the cell is enclosed within a lorica — a rigid, often silicified or organic housing with an apical pore through which the flagellum protrudes. The lorica shape and dimensions provide taxonomic characters for species differentiation within the genus. C. minutus inhabits freshwater environments, including oligotrophic lakes, bog pools, and slow-moving waters in temperate and subarctic regions. Chrysophytes thrive in cold, acidic, low-nutrient waters and serve as reliable bioindicators of water quality. The small cell size of C. minutus places it within the nanoplankton size class, making it an important prey item for heterotrophic nanoflagellates and small ciliates in the freshwater microbial food web. Some Chrysococcus species supplement photosynthesis with bacterivorous feeding. The species has not been evaluated for conservation status and is listed as Not Evaluated by the IUCN. Loricated chrysophytes like C. minutus leave fossil siliceous cysts (stomatocysts) in lake sediments, which are widely used in paleoecological reconstructions.

Coastal Silver-stiletto

Coastal silver stiletto (Acrosathe annulata) is a slender robber fly in the family Therevidae, native to northwestern Europe, including the United Kingdom, France, the Netherlands, Belgium, and Scandinavia. Adults are found on coastal sand dunes and sandy heathland, where they perch on bare sand to ambush small flying insects. Stiletto flies in the family Therevidae are characterised by a slender body, long pointed abdomen, and predatory habits; adults prey on a variety of small dipterans and other flying insects during warm, sunny periods. Larvae develop in sandy soil, where they are also predatory, feeding on other invertebrate larvae. Acrosathe annulata is a habitat specialist restricted to open, sandy coastal habitats with sparse vegetation—environments that have declined substantially across northwestern Europe due to dune stabilisation, recreational disturbance, and the cessation of traditional dune management. The IUCN lists it as Least Concern, though regional conservation bodies in the United Kingdom have flagged population declines. It is considered an indicator of high-quality coastal sand dune habitats and is monitored through national invertebrate surveys.