Euglena Promenade

Viewing a new sample from one of the vials on my workspace is always a surprise. This time, there were an overwhelming number of Euglena present. Compared to Paramecium and Lepedella rotifers, they are small.
Euglena are protists, having a flagellum (looks like a whip) for locomotion. But by twisting their bodies, they can also move around in the water. This is because they have a flexible "pellicle" (a protein layer) or envelope around them which allows them to change shape. Many of the Euglena in this video are doing just that: rolling into a ball, then returning to their long shape, and moving away.
This action is called "metaboly", which is the biological ability of some cells, especially protozoans, to alter their shape and then return to their original shape.
Many Euglena have chloroplasts in their single-celled bodies. This allows them to survive using photosynthesis, like plants. But they can also eat plant and animal matter!
They are found in both fresh water and salt water. If the water dries up, or food is scarce, Euglena forms a protective wall around itself and lies dormant as a resting cyst until conditions improve.
Video was captured with a Hayear HY-500 camera, Amscope M620 microscope with 4X, 10X, 20X, 40X objectives. Additional processing completed on Mac Photo.
Original song/video "Sociably" by My-Fi Saloon @my-fisaloon8370 / @my-fisaloon8370