Amoeba from a paddy field

The sample was observed immediately after being collected from a paddy field.

As the body of this amoeba is completely transparent, it is difficult to find it among the surrounding aggregates.

Commentary by Prof. Yuji Tsukii, Hosei University
This organism is a kind of naked amoeba. To identify naked amoebae, it is necessary to know how they move. In this video, the surrounding aggregates block the view of the whole cell, which makes identification difficult.

It can be guessed from the video that the cell may be more than 100μm long and not quite flat, so this amoeba may belong to the suborder Tubulina.

At the top of the cell there is a transparent part without particles, called a　hyaline cap. It is unusual that, in spite of its large size, this cell contains relatively few large particles. Usually a large amoeba has many more small particles.

Is this amoeba really a large type and is the scale of this video correct?

Sampling Date : 17 August 2006

Sampling Site : KASHIMADAI paddy field  Google Map