Homalozoon ciliate and its attack on rotifer

[Microbia]

Hello.
I was thrilled to see this action

[75RR]

Great catch!!

[zzffnn]

Amazing! The rotifer prey was almost digested 20 minutes after being swallowed. Thank you for sharing!

I am guessing you are not just lucky - you spent lots of time scanning and waiting for a short scene like this, right?

[billbillt]

This is very cool... Very good!....

BillT

[Microbia]

Thank you all!

I am guessing you are not just lucky - you spent lots of time scanning and waiting for a short scene like this, right?

Not lucky at all. I spent the whole yesterday night watching this Homalozoon (I guess 6-7 hours:))
The matter was that I was very curious to see the way it eats. I didn't find any video of its feeding behavior. So I couldn't just let it go:) It is quite rare.
I thought it would catch some small ciliates and didn't expected it to grab a rotifer.

[75RR]

I downloaded it and slowed the first part down (the strike) in order to see if I could distinguish how it was done, no luck. It does seem as if it stabbed it with something that apart from stunning it allowed it to reel it in - some sort of harpoon like apparatus. Perhaps it might be visible in Phase contrast.
Pretty efficient hunting and digesting as well, one would think it would, anaconda like, take a week to digest such a large meal.

[Microbia]

I also tried to slow down the strike and hoped to see trichocysts.. Nothing could be seen.

[vasselle]

Bonjour.
Alors là je dit tout simplement bravo.
Car elle est tout simplement superbe cette vidéo car c'est là première fois que je vois ça.
Encore bravo pour votre travail et merci pour le partage.
Cordialement seb

[Tom Jones]

Wow Very, very nice.

Tom

[Johann]

Awesome video - very interesting

[billporter1456]

An incredible video! I am sure you were thrilled when after watching for so long, you witnessed this amazing feeding behavior. I doubt very much if anyone anywhere has recorded a better one. Thanks for sharing it.

[Bruce Taylor]

Another wonderful video! Truly, you have an amazing ability to record ciliate predation.

I've watched Homalozoon for years and have never seen one take a meal.

[billporter1456]

Thank you all!

I am guessing you are not just lucky - you spent lots of time scanning and waiting for a short scene like this, right?

Not lucky at all. I spent the whole yesterday night watching this Homalozoon (I guess 6-7 hours:))
The matter was that I was very curious to see the way it eats. I didn't find any video of its feeding behavior. So I couldn't just let it go:) It is quite rare.
I thought it would catch some small ciliates and didn't expected it to grab a rotifer.

You must have had to re-hydrate that slide numerous times? By the way, I recall you saying that you were using a "no name Chinese" microscope with objectives you bought on eBay. Your images look crisp and clear, so I'm curious about the objectives you are using.

[Microbia]

Thank you everyone for the kind words!

You must have had to re-hydrate that slide numerous times?

Yes, I needed to add a drop of water every 20 minutes. I added the water from the samples that contained small ciliates, I didn't know that Homalozoon wasn't interested in them

By the way, I recall you saying that you were using a "no name Chinese" microscope with objectives you bought on eBay. Your images look crisp and clear, so I'm curious about the objectives you are using.

My objectives are Chinese too. I bought a set of plan objectives from this store on Ebay http://stores.ebay.com/Cnscope/Infinity ... 34.c0.m322

[Aenima]

Wow, amazing video and scene.

I downloaded it and slowed the first part down (the strike) in order to see if I could distinguish how it was done, no luck. It does seem as if it stabbed it with something that apart from stunning it allowed it to reel it in - some sort of harpoon like apparatus. Perhaps it might be visible in Phase contrast.
Pretty efficient hunting and digesting as well, one would think it would, anaconda like, take a week to digest such a large meal.

Is the harpoon thingy it used toxic in some way? is that why it seemed to be dazed? very interesting that these little critters have sophisticated weapons and tactics - not something i've ever really studied before so apologies if it's a silly question

Thanks.

[Microbia]

Wow, amazing video and scene.

Thank you!

Is the harpoon thingy it used toxic in some way? is that why it seemed to be dazed? very interesting that these little critters have sophisticated weapons and tactics - not something i've ever really studied before so apologies if it's a silly question

Yes, it is toxic. The feeding behavior of Homalozoon involves 5 stages (similar to all ciliate predators, I think) : contact of prey with the oral rim of Homalozoon --> ejection of toxin --> paralysis of the prey --> grasping --> swallowing

[Bruce Taylor]

(similar to all ciliate predators, I think) : contact of prey with the oral rim of Homalozoon --> ejection of toxin

Oral toxicysts are an innovation of certain litostomatean ciliates only ("haptorians," in the loose sense, i.e. including Rhynchostomatia). Most ciliate groups--many of which include ambitious predators--do not have them, although some of these possess toxic somatic extrusomes of one kind or another (like the defensive pigmentocysts of Blepharisma and Climacostomum).

[Microbia]

Oral toxicysts are an innovation of certain litostomatean ciliates only ("haptorians," in the loose sense, i.e. including Rhynchostomatia). Most ciliate groups--many of which include ambitious predators--do not have them, although some of these possess toxic somatic extrusomes of one kind or another (like the defensive pigmentocysts of Blepharisma and Climacostomum).

Thank you, Bruce, for your valuable correction. So far, I've seen only predaceous ciliates with toxicysts, so I made a wrong conclusion.

[hkv]

Fantastic!

[Radazz]

WOW!
I need to not stay away so long, catching up on everyone's great work.
Jim