Description of Ceratium compressum
provided by BioPedia
Ciliate, 25-60 x 15-35 microns, usually smaller than 50 microns. Shape a broad spindle-form. Often easily sigmoid and somewhat flattened. Macronucleus spherical in body center. 1 micronucleus. Contractile vacuole below the body centre. Extrusomes inconspicuous. About 50-60 longitudinal ciliary rows, whose basal bodies separated far form 3 typical, diagonal ciliary spirals. At the posterior end one cilium about 0.5 times body length. Oral apparatus subapical, about one quarter body length, funnel-shaped. Two nearly circular ciliary rows; a third very short row located at the ventral end of the mouth opening. At the right end of the rows several tiny adoral organelles.
