Algal cells among particles

A long colony of green algal cells is rigidly connected, resembling a pole. It moves in a straight line, either forward or backward, toward a particle. Another type of individual green algal cell is half-hidden behind the particle. A Euglena cell is attached to the particle and does not move. There are numerous unmoving diatoms surrounding the particles.

Commentary by Prof. Yuji Tsukii, Hosei University
Closterium acerosum is half visible behind a black particle

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

Oscillatoria is approaching the particle from the lower right side.

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

Its trichome is narrow, cell length is short, and there are no visible particles in the septum between cells. Based on these features, the organism may be Oscillatoria simplicissima.

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

But to conclusively state that the organism is Oscillatoria simplicissima, it is necessary to measure the width of its trichome, length of each cell, and to confirm the absence of any particles in the septa.

Sampling Date : 18 October 2009

Sampling Site : Hirose River A  Google Map

A leisurely green alga

A large algal cell more than 600 microns long is moving slowly. Both ends of its straight body are slightly tapered. We can see green particles inside the cell.

Commentary by Prof. Yuji Tsukii, Hosei University
This is Closterium acerosum which lives in paddy or marsh areas.

Two ways of moving are characteristic of this group.

One is to move by attaching first the front end of the cell followed by the back end to the bottom surface as in the case of Closterium moniliferum.

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

The other method is by gliding as performed by this Closterium acerosum.

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

Sampling Date : 18 October 2009

Sampling Site : Hirose River A  Google Map