MicrobeHunter.com Microscopy Forum

Francisco wrote: ↑

Mon Jan 22, 2024 4:07 pm

Magnificent images.
Do you have an SEM?
Greetings

Greetings to you too, Francisco! I do not have an SEM, but I am able to use a very nice one at the Canadian Museum of Nature, where I am a Research Associate.

The discussion of Galeripora dentata on another thread prompted me to share a few images I've made of these lovely critters. Netzelia corona , from the Mer Bleue bog in Ottawa: Netzelia corona.jpg Lesquereusia gibbosa : lesquereusia gibbosa.jpg ...and Galeripora dentata , from a fen in the woods beh...

the individual I encountered manifested active vacuoles, Hi Charlie! Arcellid amoebae have the ability to form pockets of gas, which they use to right themselves when inverted or to relocate themselves by flotation. Here's a short paper describing the behaviour in Galeripora discoides (then known a...

Really nice video, Francisco! This species is now in the genus Galeripora.

It is not a ciliate, but a flatworm of some kind. The round structure appears to be a gravity-sensitive organ called a "statocyst," used for orientation (they are found in marine acoelomorphs, but I'm not sure what other groups might have them). I don't know much about animals, so I can't help with ...

Yes, exactly! S. roeselii in an early stage of division (vermiform macronucleus, no cortical pigments).

Very nice! If you're curious, the species is S. teres.

As WWWW says, it is a spathidiid (but not necessarily in genus Spathidium). Magnification and resolution are too low for identification to genus level.

On the basis of the cell shape, I think it's likely to be a species in the S. amphoriforme complex. It somewhat resembles S. securiforme (previously a variety of amphoriforme , elevated to species level in 2017). However, there really isn't much to go on, here, except for the coarse morphology. We d...

It's not a rotifer. It's a vaginicolid ciliate (Vaginicola, Cothurnia, etc.). We don't see the base of the base of the lorica, so I'm hesitant to propose a genus-level identification.

Thanks for fixing that link! On the other hand, it is a bit sad to know that, as an amateur, little can be done to identify the critters we see every day. We can still identify them...just not necessarily to species . ;) Even genus can be difficult in some groups. Since Vorticella was split in 1976,...

Identifying Paramecium species in the light microscope is actually quite difficult, and often impossible. At best, it requires a close inspection of features that are difficult to see, such as micronuclei and the pores of the contractile vacuole. Accurate measurements are also important, and multipl...

There are ciliates that form reproductive cysts, which are a little like egg sacks.

Yes, a ciliate feeding frenzy. The usual suspect in a scene of this kind would be a histophagous (tissue-eating) Tetrahymena.

Could you post video footage? It's hard to see what's going on in this image. The ratio of anterior cilia/polykinetids to body length would be unusual for Stentor (more like a choreotrich or peritrich, for instance...however, it is really hard to tell from what we see here). Does the .1 mm on your s...

Very nice! This is an Arcella in the hemisphaerica/rotundata/gibbosa complex.

Yes, Das Leben is a handy little guide. Keep in mind, though, that it shows only a tiny fraction of the real diversity in fresh water, and that the taxonomy is outdated. The same goes for most such "field guides," unfortunately.

Nice video! :) It is not Gonostomum affine , or any member of the family Gonostomatidae. Ciliates in that family have an arrangement of oral structures (adoral zone of membranelles, or "AZM", and associated undulating membranes) which is known as the "Gonostomum pattern". In that pattern, the AZM ru...

@MitchW It's a Stentor. Identification to species would begin with a clear view of the macronucleus.

Re. sources...I can't think of many comprehensive guides to heterotrophic flagellates, and the ones I know of are old and difficult to get. Part of the problem is the word "flagellate" itself, an obsolete classification that ropes together all kinds of unrelated organisms. The ancestor of all eukary...

I looked it up online and now assume that it doesn't have a lorica, just a spiral body. Is that right? Yes, that's right. It's an understandable error. The pellicle is thick and rather stiff, and does look a bit like a lorica! Heteronema spirale is a heterotrophic (non-photosynthetic) euglenoid, fi...

Heteronema spirale.

I believe this is Mastigamoeba setosa.

This is Clathrulina elegans . Biflagellate swarmer cells sometimes attach to mature organisms to form daisy-chain colonies, as in this rather cool image by Martin Kreutz: https://realmicrolife.com/wp-content/uploads/2023/09/Clathrulina-elegans-P7194341-Martin-Kreutz.jpg From: https://realmicrolife.c...

This is two stylonychine ciliates (probably Stylonychia) in conjugation. They are exchanging gametes.

Well, that worked perfectly. One quick puff with the bulb blower and all was clear.

Thanks for the help, everyone!

Thanks again, PeteM. I'll see if I can remove the debris with a bulb blower and/or soft brush, but if it comes to using solvents (even water!), I think I'll let them bring in the technician!

I was back at the museum yesterday, and set out to analyze the source of the dark spot in the light path. I brought a centering telescope, but it wasn't needed in the end because the problem was not subtle. ;) There's some loose debris inside the Nomarki/DIC intermediate tube, and a big piece is stu...

Thanks for the advice, PeteM! I'll bring a centering telescope on my next visit (and an air-blower bulb).

Well, I managed to remove the drawing attachment. It did indeed have a spring-loaded plunger, as PeteM suggested (with a slot-headed screw in the end of the knurled knob). Knowing that "stuck oil" was probably the issue, I was a bit more forceful with the assembly, and pushed the dovetail against th...