Help with ciliates ID

[Javier]

Today I observed a drop of water from a flower vase and found these two ciliates specimens. Could you please help me with the ID?

Also, I found it interesting to observe bacteria inside the "circles" of the first specimens, under oblique light. Are those food vacuoles?

Sorry about the dust on the eyepiece on the second part of the video...

Thank you in advance for your help!

[Bruce Taylor]

The first ones are Tetrahymena. The "circles" are food vacuoles, as you say. The second ones are peritrich ciliates in their migratory "telotroch" phase. Stalked peritrichs (Epistylis, Zoothamnium, Vorticella, etc.) sometimes undergo a change in body shape, abandon their stalks and swim away to a new location. These telotrochs tend to be roughly cylindrical in shape.

[Javier]

Thank you, Bruce.

I suspected those could be Vorticellas. The sample had quite a few of them. I have seen them swimming free, but I remember them being less tubular and more bell-shaped, even in this stage. It's good to learn about the telotroch phase of these peritrich ciliates.

I appreciate you taking the time to share your knowledge here.