Heterocyte and akinete – producing cyanobacteria
Primarily occurs in terrestrial habitat.
Association with fungi in lichens and with some
bryophytes and vascular plants.
Moist rocks and cliffs.
In wet meadows.
At the edges of shallow lakes.
Bent or naked filaments of round cells are held
in a firm mucilaginous matrix to form colonies.
The sheaths colored by yellow, brown or black.
Transiently motile hermogonia are produced
these typically have heterocytes at the ends.
Nostoc is frequently abundant in flooded rice
paddies where it contributes to the fertilization of
some 2 million hectares.
Primarily planktonic in fresh waters and
marine waters such as the Baltic Sea
some forms can be nuisance bloom formers
and toxin producers.
Consist of filaments of spherical cells
resembling in a mucilaginous matrix .
Molecular phylogenetic analyses indicate
that Anabaena is not monophyletic group
separated into multiple classes.
Occurs in the Baltic Sea and in eutrophic inland water.
Consist of distinctive aggregations of filaments (so
large as to be visible).
Molecular phylogenetic within Anabaena as the
May not be monophyletic.
Aphanizomenon that which makes itself invisible.
Large blooms may form in the Baltic Sea and in
eutrophic inland waters.
Occurs in freshwaters including soft, acid
Forming dark green patches on submerged
vegetation and on moist soil.
Filaments of vegetative cells ( square or
Heterocyte at one end are enclosed in loose
A large ,highly or nemented akinete may
develop from the lowermost vegetative cell.
Plaktonic bloom-former in eutrophic temperate.
Tropical freshwater around the world.
Rectangular cells occur in linear or coiled
filments having a basal heterocyte.
Akinetes may form basally.
If akinetes are not present , correct species
identification may be difficult.
Important nitrogen – fixing.
C.Raciborskii this species produces the
Entangled among submergent vegetation in
freshwater lakes (soft or acidic water ).
Filaments are enclosed in a sheath of variable
Highly false branched usually at a heterocyte (
single false and sometimes double false branches
The frequency of false branching gives these algae a
Forms dark tufted mats in masses of other algae.
Vegetation in lakes.
On terrestrial surfaces ( stones , wood and soil ).
Often double false branches occur , this result has
been interrupted by death of a cell .
Less commonly by heterocyte differentiation.
Heterocyte wall may be darkly pigmented.
Sheath is tough and sometimes clearly layered (
colored brown or orange ).
It is a phycobiont in several orders of lichen.
Occurs in freshwater habitat attached to
Akinetes occur adjacent to basal heterocytes
( sometimes appearing in chains).
Gloeotrichia colonies often detach from
substrate , becoming planktonic.
Growths can reach bloom properations.
Some species are aquatic , attached to submerged
wood or other algae.
Form tufted mats or cushions on submerged
portions of lake macrophytes.
The filaments are more than one cell in width as
(multiseriate or pluriseriate).
The primary phycobiont in certain lichens and is
associated with boreal mosses.
Contributes to nitrogen availability.