Cylindrospermopsis
Cylindrospermopsis
Cylindrospermopsis is a genus of filamentous cyanobacteria primarily found in freshwater ecosystems. They are well-known for their nitrogen-fixing capabilities and the production of potent toxins such as cylindrospermopsin. Originally native to tropical and subtropical regions, they are increasingly spreading to temperate zones due to climate change. These organisms often form dense blooms that can significantly impact water quality and aquatic biodiversity.
Details
Oxygen production
Produces oxygen during the light phase through photosynthesis.
Habitat function
Forms dense algal mats or suspensions in the pelagic zone, reducing light penetration.
Nutrient uptake
High efficiency in phosphate uptake and utilization of dissolved organic nitrogen.
Food source for
Only limitedly suitable as a food source for zooplankton due to toxicity and morphology.
Human use
No direct use; poses a significant risk to drinking water production and recreational tourism.
Ecology
Ecological role
Primary producer; can damage the entire aquatic food web during mass developments through toxin production and oxygen depletion.
Natural predators
Limited by herbivorous zooplankton such as Daphnia, which are often inhibited by the toxins.
Competitor species
Other cyanobacteria (e.g., Microcystis spp.) and various green algae species.
Ecosystem service
Oxygen production and nitrogen fixation during nutrient-poor phases.
Scientific profile
Profile
Distinguishing features
Possesses specialized cells: terminal, usually teardrop-shaped heterocytes for nitrogen fixation and subterminal akinetes (resting stages). Gas vacuoles (aerotopes) for buoyancy regulation are present.
Reproduction
Asexual via fragmentation of trichomes (hormogonia formation) and germination of akinetes (resting cells).