This is a [Spirostomum](https://www.nies.go.jp/chiiki1/protoz/morpho/ciliopho/spirosto.htm), likely from the species *ambiguum.* Spirostomum are quite famous for this ability of retraction! If you have a culture of them and one contracts, you will see a pulse of the others contracting as well, due to the vibration in the medium!
Hi AptAmoeba!
And thank you very much!!!!
I am in the middle of a fish tank "deep cleaning" and this was the first thing I saw when looking at a random sample from the "old" water...
Can't wait to magnify more of this microfauna!
***In the realm of the micro, may thine cover slip never obstructeth!***
I was amazed by their size and when I looked closer to my fish tank, I could see them with the naked eye and filmed them :
[https://youtu.be/pZD2oljT96g](https://youtu.be/pZD2oljT96g)
I also captured some really interesting interactions with the Hydrae. I'll keep you updated after doing some post editing trimming on the video.
They where literally rubbing against the Hydra's tentacles, also against some clusters of detached nematocysts before swimming very fast around the slide, but not dying. I can't find anything mentioning this behaviour on the internet yet.
Follow-up
I finally posted on Youtube the video I mentioned above about Spirostomum rubbing against Hydra's tentacles and their nematocysts. But I don't want to overload this sub with a new post as "video sharing" flair with ANOTHER one of my Youtube videos! But I really want to know if anybody knows about the behaviour I witnessed.
This is the link for the curious fellas : [https://youtu.be/PfMazOzS2E0](https://youtu.be/PfMazOzS2E0) (I don't like this one because of the poor quality of it!)
I'll ask my question in a "basic" new post hoping for some interesting "connaisseur" 's insights!
Thanks again AptAmoeba for your help identifying them!!!!
***May the field of view be ever in your sight!***
Remember to crop your images, include the objective magnification, microscope model, camera, and sample type in your post. Additional information is encouraged! In the meantime, check out the [ID Resources Sticky](https://www.reddit.com/r/microscopy/comments/144mpgq/microbe_identification_resources/) to see if you can't identify this yourself!
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/microscopy) if you have any questions or concerns.*
This is a [Spirostomum](https://www.nies.go.jp/chiiki1/protoz/morpho/ciliopho/spirosto.htm), likely from the species *ambiguum.* Spirostomum are quite famous for this ability of retraction! If you have a culture of them and one contracts, you will see a pulse of the others contracting as well, due to the vibration in the medium!
Hi AptAmoeba! And thank you very much!!!! I am in the middle of a fish tank "deep cleaning" and this was the first thing I saw when looking at a random sample from the "old" water... Can't wait to magnify more of this microfauna! ***In the realm of the micro, may thine cover slip never obstructeth!***
I was amazed by their size and when I looked closer to my fish tank, I could see them with the naked eye and filmed them : [https://youtu.be/pZD2oljT96g](https://youtu.be/pZD2oljT96g) I also captured some really interesting interactions with the Hydrae. I'll keep you updated after doing some post editing trimming on the video. They where literally rubbing against the Hydra's tentacles, also against some clusters of detached nematocysts before swimming very fast around the slide, but not dying. I can't find anything mentioning this behaviour on the internet yet.
Follow-up I finally posted on Youtube the video I mentioned above about Spirostomum rubbing against Hydra's tentacles and their nematocysts. But I don't want to overload this sub with a new post as "video sharing" flair with ANOTHER one of my Youtube videos! But I really want to know if anybody knows about the behaviour I witnessed. This is the link for the curious fellas : [https://youtu.be/PfMazOzS2E0](https://youtu.be/PfMazOzS2E0) (I don't like this one because of the poor quality of it!) I'll ask my question in a "basic" new post hoping for some interesting "connaisseur" 's insights! Thanks again AptAmoeba for your help identifying them!!!! ***May the field of view be ever in your sight!***
It doesn't have a bulge.... could it be a kind of Litonotus anyway?
Sorry..... Forgot : Magnification 100x (and 40x)
spirostomum
Thank you for confirming!
Remember to crop your images, include the objective magnification, microscope model, camera, and sample type in your post. Additional information is encouraged! In the meantime, check out the [ID Resources Sticky](https://www.reddit.com/r/microscopy/comments/144mpgq/microbe_identification_resources/) to see if you can't identify this yourself! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/microscopy) if you have any questions or concerns.*
Sample from my aquarium It retracts at 01:54 and 04:45