Prorodon (?) or Ophryoglena (?) dividing

[NachoBen]

I saw this critter, half divided, escaping from its reproductive cyst. This is why I think it could be Prorodon instead Ophryoglena. However, I can not see the typical "basket mouth".




Can anyone help me, please?

Thank you very much.

[Bruce Taylor]

Because of a taxonomic error in the early 20th century, ciliates identified in older texts as "Prorodon" are now considered holophryids (Holophrya, Vdacnyophrya, etc.), and the genus Prorodon now comprises ciliates previously called Pseudoprorodon.

The critters in your video have a contractile vacuole on the side of the cell, at mid-body, so they are clearly not prostomateans of any kind. Holophryids (such as Prorodon sensu Kahl) have their CV at the posterior.

We don't see the mouth. However, these guys look and behave very much like Ophryoglena (that slow rotation is typical). As it happens, nearly all members of that genus (with the exception of O. catenula) divide in reproductive cysts. So, this is probably Ophryoglena.

[NachoBen]

At first I did think of Ophryoglena, but it was impossible to me to see the 6-shaped mouth.

Also, I didn't know that this species reproduces in cysts. I have a lot to learn.

Thanks again, Bruce, and sorry for the poor quality of the video.

[Dennis]

Nacho Ben,
That is some great footage !

[NachoBen]

Thanks, Dennis. I hope it will be a bit better next time!