A rapidly swimming flagellate

This organism covered with a reddish-brown shell may be a flagellate called Trachelomonas. It is swimming around too rapidly for us to clearly see its flagellum.

Commentary by Prof. Yuji Tsukii, Hosei University
It is difficult to say if this organism is Trachelomonas. The organism in this video is different from a typical Trachelomonas, which has a spherical, eliptical or spindle-shaped shell all wuthout a dent. This organism has a dent near the center and may have one or two flagella. If this organism were trachelomonas, it would have only one flagellum extending forward.

Algae are often covered with a shell. In particular, green algae have shells of various shapes. The organism appearing in this video, however, is too small for us to recognize the characteristic shape of its shell.

(Green algae with shell:Please refer to the following additional examples)

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

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

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

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

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

Sampling Date : 28 May 2009

Sampling Site : Hirose River B  Google Map