Algae with horseshoe-shaped chloroplast

The spaces between particles are passage ways for microorganisms. Bacteria, flagellates, small ciliates and diatoms meander among the particles, while one algal cell with a strange, horseshoe-shaped chloroplast is standing still. Perhaps this chloroplast is a special type referred to as cyanelle.

Commentary by Prof. Yuji Tsukii, Hosei University
This is a diagonal top view of Paulinella.

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

This organism belongs to the group Paulinera, and the slender green structure in its shell is not a chloroplast but a type of symbiotic blue green algae called cyanelle.

Sampling Date : 02 July 2009

Sampling Site : Hirose River A  Google Map