Communication between different organisms?

An inactive flagellate is sitting completely still without moving. One after another, two small ciliates come to the front of the inactive flagellate, and stop as to check on it before they leave. Soon these ciliate return for another visit, and it looks like the two different kinds of organisms are communicating. To our surprise, the flagellate suddenly becomes active, contracting its body and shooting out of our view.

Commentary by Prof. Yuji Tsukii, Hosei University
The title and the commentary of this video should be changed, because the organisms shown are flagellates, not ciliates. In this video, we can see two types of flagellates belonging to Euglenales and Cryptomonadales.

The Euglenales organism does not have any cilia and a few relatively large pyrenoids can be seen inside of the cell. Therefore, the organism is probably Euglena agilis, but we cannot rule out the possibility that the organism could be E. viridis. Because cell outlines are similar in both E. agilis and E. viridis

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

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

The shape of the chloroplasts is also an important point in distinguishing the above two Euglena species. However it is difficult to see the precise shape of the chloroplasts in this video.

In this video, the Cryptomonadales organism has light-brown chloroplasts along the sides of the cell with a pyrenoid at the center. These characteristics are typical of Cryptomonas or Chroomonas.

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

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

Sampling Date : 09 August 2009

Sampling Site : Hirose River B  Google Map