Spinning and resting
A ciliate of light green color and flat oval shape is resting. Its long cilia are extended in all directions. After a while, as if suddenly awakened, it spins vigorously and shoots out of our field of view.
Commentary by Prof. Yuji Tsukii, Hosei University
The cilia of this organism and other features can be observed clearly in the first part of this video. The cytostome (mouth) is most likely located in the depression in one side of the cell. From the depression, we can see a bundle of long cilia sticking out. This is called the velum, which sometimes appears as a curtain-like line of cilia.
Judging from the above features, this organism may belong to genus Pleuronema.
Sampling Date : 09 August 2009
Sampling Site : Hirose River B Google Map