Vorticella microstoma (photo Dr. Marina Ettl)

Sessile ciliates

  • 35 – 85 µm
  • single-celled and with muscle
  • pear-shaped with small mouth area
  • extended C-shaped macronucleus parallel to longitudinal axis

 

In activated sludge:

  • in the upper load range
  • with oxygen concentration < 1 mg/l