Chroococcus limneticus

Phylum: Cyanobacteriophyta
Class: Cyanophyceae
Order: Chroococcales
Habitat: planktonic
Distinctive features: rare.
Organization: colonies of 2-8 cells, rarely as single cells
Color: blue green
Cell shape: sphere
Colony shape: spherical
Cell diameter (D): 4 – 10 μm
Cell biovolume: 35 – 500 μm³
Biovolume equation: Sphere V, μm³ = 4/3 π (D/2)³
Cells per colony: 4-30

Morphological features

Colonies of 4-30 spherical cells that remain attached after cell division (Plate 1, 2). With wide colorless translucent gelatinous slime (Plates 1, 2). With envelopes around cells. No gas vacuoles.

Plate 1. Chroococcus limneticus from Lake Kinneret. Cells remain attached after division, have no gas vacuoles, with a distinct envelope. Photo by Alla Alster, Aug. 2007.

Plate 2. Chroococcus limneticus from Lake Kinneret, shore sample. Photo by Alla Alster, Sep. 2007.

Ecology

The species rarely occurs (Fig. 1).

Figure 1. Time series of Chroococcus limneticus mean epilimnion colony abundance (colonies mL^-1) Lake Kinneret, 1996-2020.

Figure 2. Chroococcus limneticus abundance (colonies mL^-1) vs. environmental parameters recorded at the site and time of sampling, showing tendency for higher abundance at higher temperature, lower alkalinities and higher pH (to a limit at 9.0).

Environmental conditions

Chroococcus limneticus was more abundant at warmer water temperatures, lower , and higher pH – to a limit of pH 9.0 (Fig. 2).

Cite this record as: Dr. Tamar Zohary, Dr. Alla Alster. 7 August 2026. Electronic publication. Israel Oceanographic & Limnological Research. https://kinneret-algae-atlas.org/ Searched on —.