Video, ciliate predation: theft, ingestion, digestion. IDs?

[rjlittlefield]

5X speedup video at: https://youtu.be/wnBRTdEE4ag

This was a lucky catch. The video begins with some large predatory ciliate having captured some smaller ciliate, apparently preparing to eat it. In the first 15 seconds of the video, a second large ciliate intercepts the first one and wrestles away the prey. At about 0:20 and continuing through 0:45, the large ciliate successfully ingests the prey, losing its membranous front end and assuming a fat oval shape with no projections. At that same time, the first predator leaves the scene, apparently figuring there's no longer any chance of a meal here. Processing of the prey and resumption of more normal shape continues through 1:00 (5 minutes of observation). From there through the end of the video (2:18, another 6 minutes real time), the predator gradually finishes processing its meal, regains its normal structure, and starts sniffing around for something else to eat.

Shot with a 20X objective, cropped and scaled in post-processing to about 0.53 mm field width. Each of the panels shown below is about 140x160 microns.

If anybody has an ID for the participants in this little eco-drama, I will appreciate knowing.

Hope you find this interesting!

--Rik

[René]

Nice detail Rik, got a bit dizzy from all the traffic whizzing by ;-)
Hope Bruce can help you with ID,

best, René

[carlos.uruguay]

Very interesting video sequence

[Jacek]

Interesting, nice video
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[Bruce Taylor]

Wow, great catch!

The predator has two macronuclei and a slit mouth, and is clearly pleurostomatid (not a tracheliid or dileptid). The posterior contractile vacuole is conpicuous, but it's hard to be sure whether there is a second one in mid-body. It very much resembles Litonotus varsaviensis, as redescribed by Foissner et al, in the fourth volume of their "ciliate atlas", 1995.

I can't say anything about the victim.
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[zzffnn]

Nice video, Rik!

Were you using AmScope achromat objectives and matching eyepieces (if any)? I found CA colors pretty low, for what they are. Did you digital desaturate/remove CA colors?

Just curious. Thank you!
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[rjlittlefield]

All, thanks for the comments!

Bruce, many thanks for the ID. If I have time, I'll try to catch some better shots. What parts of the anatomy would you particularly like to see?

zzffnn, this particular objective is one that I bought ages ago at Edmund Optics. It's a basic achromat, which I selected at the time because it had barely enough working distance (3mm) to use for macro stacking. I swapped it into the Amscope turret to get a nice sequence 4X, 10X, 20X, 40X. The speeded-up video did have some brightness/contrast/color adjustments, which interact with each other in ways that I don't fully understand. So to answer your question I have extracted a single frame from the video (using Camtasia) and saved it out to HERE with no further processing. It does seem to be pretty low CA.

--Rik

[Bruce Taylor]

[fpelectronica]

Very nice
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