Scaled golden alga
Mallomonas acaroides
Mallomonas acaroides is a unicellular alga from the class Chrysophyceae, characterized by an armor of overlapping silica scales. These scales often bear long, movable silica bristles that serve for protection against predators and increase buoyancy. The species lives planktonically in standing freshwater bodies and typically prefers cooler, oligotrophic to mesotrophic waters.
Details
Oxygen production
Contributes to the oxygen saturation of the upper water layers.
Habitat function
Serves as the base of the food chain in pelagic freshwater habitats.
Nutrient uptake
Absorbs phosphates and nitrogen compounds directly from the open water.
Food source for
Filter-feeding zooplankton and microorganisms.
Human use
Scientific use in paleolimnology to reconstruct past environmental conditions.
Ecology
Ecological role
Primary producer in aquatic ecosystems and an important component of the microbial loop.
Natural predators
Herbivorous zooplankton such as rotifers, water fleas (Daphnia), and heterotrophic ciliates.
Competitor species
Other phytoplankton species such as diatoms or green algae under similar nutrient availability.
Ecosystem service
Oxygen production through photosynthesis and carbon fixation in inland waters.
Threats
Heavy eutrophication of water bodies and extreme pH fluctuations outside the tolerance range.
Scientific profile
Profile
Distinguishing features
Possesses silica scales with a specific ultrastructure (V-rib, dome) and serrated bristles (setae). Definitive species identification usually requires electron microscopy of the scale morphology.
Reproduction
Asexual reproduction by longitudinal fission; sexual reproduction via isogamy, leading to the formation of thick-walled, silicified resting cysts (stomatocysts).
Protection & threats
Status not on standard scale
Main threats
Eutrophication (nutrient input), anthropogenic acidification of soft-water lakes, and climate-change-induced warming of cold-water habitats.
Conservation measures
Maintenance of nutrient-poor water conditions, reduction of diffuse nutrient inputs from agriculture, and protection of bog water bodies.