Spindle-shaped desmid
Closterium acerosum
The spindle-shaped desmid is a unicellular green alga belonging to the order Desmidiales. It is characterized by elongated, narrow cells that taper at the ends and contain two large chloroplasts. Unlike many other desmids, it lacks a central constriction (sinus). It is primarily found in stagnant, oligotrophic to mesotrophic waters as well as in peat bogs.
Details
Oxygen production
Produces oxygen as a byproduct of photosynthesis.
Habitat function
Part of the phytoplankton, which forms the base of the aquatic food web.
Nutrient uptake
Absorbs dissolved nitrogen and phosphorus for biomass formation.
Food source for
Zooplankton and benthic microinvertebrates.
Human use
Used in research as a model organism for cell biology and morphogenesis.
Ecology
Ecological role
Important primary producer in aquatic systems; serves as a food source for microfauna.
Natural predators
Protozoa (ciliates), rotifers, small crustaceans.
Competitor species
Other phytoplankton species such as diatoms or other green algae.
Ecosystem service
Oxygen production and carbon fixation in inland waters.
Threats
Eutrophication of water bodies, pesticide input, destruction of peat bogs.
Scientific profile
Profile
Distinguishing features
Large, robust cells with a central row of 7 to 15 pyrenoids per semicell. The cell wall is smooth and colorless, but may become yellowish or brownish with age. Characteristic are the terminal vacuoles containing numerous dancing gypsum (barite) crystals.
Reproduction
Asexual by vegetative cell division; sexual by conjugation, where two cells fuse to form a thick-walled, usually smooth and spherical zygospore.
Protection & threats
Status not on standard scale
Main threats
Loss of small water bodies through infilling or drainage; extreme acidification of habitats.
Conservation measures
Protection and creation of ponds and pools; reduction of pesticide input in agricultural landscapes.