The Amoeba proteus is a large protozoan and belongs to the Phyllum Sarcodina.

It has an ever changing shape and is approximately 500-1000µnm long. It can almost be seen with the naked eye.

The Amoeba proteus can be ordered from science supply companies and is the classic specimen used in the classroom to demonstrate the pseudopods in action. Other species of amoebas are either too small, too fragile or atypical in structure.

Amoeba proteus can sense light and tends to move away from it. Just before it reproduces, it rounds up into a ball with tiny pseudopodia extensions. Over the next 15 minutes or so, it splits and becomes two. The image below shows one amoeba in the final stages of splitting. Look carefully and you can see the clear channel between the two new amoebas.