A round, dark-red amoeba with a shell

A testate amoeba about 70 microns in diameter extends its pseudopodia all around and moves slowly, carrying a variety of diatoms and several particles attached to its shell. When fully extended, the pseudopodia are twice as long as the diameter of shell, and they sometimes branch at the tip. Although the job of pseudopodia is to carry small organisms to the central body by contracting, this amoeba is not actively catching food in this view.

Commentary by Prof. Yuji Tsukii, Hosei University
This top-view video shows a testate amoeba belonging to genus Difflugia moving along with its shell. The Difflugia genus is composed of many species, so it is difficult to identify this amoeba to the species level.

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

Sampling Date : 28 May 2009

Sampling Site : Hirose River B  Google Map