A ciliate with a slendar body is busily foraging among particles. Judging from the cirri in front and rear, it appears to belong to the group of Stylonychia.
Commentary by Prof. Yuji Tsukii, Hosei University
The organism is not Stylonichia as mentioned in the video title; rather it belongs to genus Oxytricha or a related genus. The body of Stylonichia is hard and inflexible, so it changes directions without bending or otherwise changing its cell shape. Stylonichia is also characterized by three long cirri at the rear end.
On the other hand, Oxytricha has a soft body, and when it changes directions, the body stretches and bends toward the new direction. It is also characterized by cirri lining both sides of the cell from the tip to the rear end.
However, this video doesn’t clearly show whether or not both sides of the cell are lined with cirri from tip to rear. It looks as if there are no cirri at the midsection, which would suggest that the organism is other than Oxytricha.
However, it is certain that the organism is not Stylonychia.
Sampling Date : 03 July 2009
Sampling Site : Hirose River B Google Map