Why does it rotate ?

The rear end of this small oval ciliate is slightly narrow and bent. The organism rotates in a stationary position. No one can guess why it continues this rotary motion.

Commentary by Prof. Yuji Tsukii, Hosei University
This organism looks like it might be a fragmented ciliate, but it is also possible that this is its normal shape. Even so, it is difficult to say what genus it is. The fact that it is swimming backward is unusual, and suggests that the cell shape has been greatly transformed.

Sampling Date : 27 May 2009

Sampling Site : Hirose River A  Google Map