Pleuronema sandwiched between algae and particles

Being sandwiched between a long algae and a particle, this Pleuronema ciliate cannot move freely. Only a transparent membranous structure on one side of the body is quivering. A few long cilia at its rear end are not moving. Ciliates of various sizes are swimming nearby, and sometimes bump into the Pleuronema.

Commentary by Prof. Yuji Tsukii, Hosei University
The velum - lined cilia arranged like curtain – indicates that the organism is probably Pleuronema. If so, it may be Pleuronema marinum with a large body size.

http://protist.i.hosei.ac.jp/PDB/Im.....

Histobalantium natans has a similar body size and also has a velum. However, the velum of Histobalantium natans features cilia of variety lengths, whereas the cilia of Pleuronema marinum are all the same length.

http://protist.i.hosei.ac.jp/PDB/Im.....

It is difficult to see whether the cilia in this video are of equal length, so this organism cannot be identified with certainty.

In the video we can also see Remanella and Holosticha organisms swimming around.

Sampling Date : 27 May 2009

Sampling Site : Hirose River A  Google Map