- False branching begins
to develop as both ends
- of the filament break
through the mucilage sheath.
- The right portion
has grown quite a bit, while the
- portion to the left
is just breaking through the sheath.
- Scytonema filaments
form dark mats or tufts amongst other algae or submerged vegetation
in lakes or on terrestrial stones, wood, or soil. The trichomes
are cylindrical and isopolar, and are usually colored pale blue-green,
olive green, brownish, or even violet. The apical ends of the
filaments are not tapered, but the end cells may slightly rounded
or widened. The cells sometimes have constricted cross walls
and contain groups of long, cylindrical gas vesicles. The heterocysts
are located throughout the filaments and are rectangular and
solitary, with darkly-pigmented cell walls. The trichomes are
contained within mucilage that is commonly tough, wide, sometimes
layered, and may be colored brown, yellow, or orange.
false branching often forms when a filament breaks apart at the
site of a dead cell. Both ends of the filament then break through
the mucilage sheath and continue to grow as "branches".
Occasionally, false branching also forms at a heterocyst where
the filament breaks apart in a similar manner.
- Both pieces of the filament
have grown extensively,
- forming the characteristic
false branching pattern.