View Full Version : Some Freshwater Microbes, or: Why I swim with my mouth closed

Bruce Taylor
02-23-2015, 12:31 PM
Some pond porn, for JoP (as promised).

A dainty one-celled critter, about 34 Ám long (.034 of a mm, a bit over a thousandth of an inch):


The green granules in its body are symbiotic algae. This fellow gives them a safe place to grow and multiply, inside his transparent body and see-through house. In return, they provide him with doses of energy, supplementing his usual diet of bacteria. When food is scarce, though, he digests them anyway. :D

This ciliate is not seen very often, and has only been written about a couple of times since the genus was discovered in 1882. More, from my blog: http://www.itcamefromthepond.com/2015/02/13/protist-homes-2-calyptotricha-pleuronemoides/

Bruce Taylor
02-23-2015, 12:49 PM
A cannibal ciliate gobbling up one of his little brothers:


John of Phoenix
02-23-2015, 01:05 PM
Thank you Bruce. I find those fascinating to no end (I miss my microscope).

Symbiotic algae and cannibalist ciliates.

One can only imagine how they'd behave if you played hard rock instead of those lullabies.

Bruce Taylor
02-23-2015, 07:46 PM
Google Irukandji and tremble.

Nasty. :D Here's one of its smaller, and less poisonous, freshwater cousins :


I normally ignore Metazoa (animals), but I wanted to demonstrate my fancy darkfield setup. ;)

Bruce Taylor
02-23-2015, 08:47 PM
Wow, that happens so fast. I have been wondering how they distinguish prey from pond scuzz. The fellow doesn't want to go around swallowing pebbles, even very small ones, but he certainly wolfed down that prey without hesitation.

Yes, there must be some kind of efficient chemotaxis happening, there. Here's another Climacostomum, eating a small flatworm (there's something particularly creepy about a single-celled guy devouring a bilaterian w/ a functioning nervous system).


Ciliates are pretty good at sensing their environment and navigating in it purposefully. Their sensory equipment -- tactile bristles, light-sensitive cortical pigments, gravity-sensing organelles, etc. -- have not been studied in much detail. It's clear that they can distinguish chemical cues, and move along a gradient toward their favoured prey. I often see histophagous ciliates flocking to a wounded crustacean, like flies to a corpse.

Bruce Taylor
02-23-2015, 08:57 PM
On that theme, look at what happens here, around the 40-second mark:


02-23-2015, 09:38 PM
My mother years ago told me not to swim in 'sweet water'. Now I know why.

Bruce Taylor
02-23-2015, 10:45 PM
If you know of any good papers on this for any alveolates then please send them my way. I have been doing literature searches on this topic, pretty lean, as you say. I am writing a review on the recently available whole genome sequence information, and the huge families of potential sensory proteins, and prediction of their evolutionary loss following transition to the more defined environments encountered in parasitic lifestyles. I will send it to you in a few weeks.

I'm looking forward to seeing it. Dunno if it's up your alley, but I enjoyed Echevarria et al (http://femsec.oxfordjournals.org/content/femsec/90/1/18.full.pdf) on the sensory biology of the tintinnid ciliate Favella (it's good to see "behaviour" being studied). There's stuff in the references pertaining to apicomplexans, too...maybe some of it involves sensing proteins (about which I know exactly nothing). Are sensory structures of interest, e.g. the dinoflagellate image-forming eye (ocelloid), or the geotactic organelle in Loxodes? Or Chlamydodon's "eyespot"?

Glen Longino
02-24-2015, 02:20 AM
Forget ISIS! We're all doomed to these ravenous microscopic bastids!;)

02-24-2015, 05:17 AM
Maybe consider plugging Your nose instead -> http://en.wikipedia.org/wiki/Naegleria_fowleri

Bruce Taylor
02-24-2015, 08:57 AM
Maybe consider plugging Your nose instead -> http://en.wikipedia.org/wiki/Naegleria_fowleri

Luckily, they prefer warm water and Canadian lakes...aren't. :D

I don't have any Naegleria to show, but here's a "real" Amoeba:


Paul Pless
02-24-2015, 09:00 AM
Bruce, didn't you get to name a 'microbe' recently?

02-24-2015, 10:49 AM
Just another source of protein.

Bruce Taylor
02-24-2015, 11:25 AM
Bruce, didn't you get to name a 'microbe' recently?

I've identified a handful of new species and sub-species/varieties, and will probably find more. I haven't named any, yet.

Undescribed organisms are not really that hard to find. The hard part is knowing what you've got, then collecting and/or culturing your critter, and finally, publishing a good description. To describe a new taxon to a professional standard, these days, you usually need to do gene sequencing, which is beyond my capability. I need to collaborate with someone who has the skills, tools, interest and time. The person I've been working with has the first three, but is quite short of time, so I have to work around her schedule. She's one of the top ciliate wranglers in the world, so lots of other people want a piece of her. Her schedule doesn't always coincide with my ability to find new specimens, and then pick the cells out one by one, with a long tube of glass, and arrange delivery. It's not happening too fast. ;)

It was a lot easier fifty years ago. You could just find a half dozen critters, write a paragraph or two about them, draw a sketch, slap a name on that sucker and publish. :D

Paul Pless
02-24-2015, 11:28 AM
So, 'ciliate' is not a scotable offense. Interesting. . .

John of Phoenix
02-24-2015, 11:35 AM
It was a lot easier fifty years ago. You could just find a half dozen critters, write a paragraph or two about them, draw a sketch, slap a name on that sucker and publish. :DHave you picked any potential names for critters you'll get to name? Something along the lines of "Bruceilla" or "Bilgeitacia"?

02-24-2015, 02:07 PM
I've swum in places where it,s not your mouth you need to keep clamped shut, and a condom is a good idea too... and there's other little buggers that get in the interstices between your toenail and the squidgy bit of skin on the side. when you start seeing the big floaters drifting across your field of vision go and see that nice man in the school of tropical medicine or whatever your homeland version is...

Bruce Taylor
02-24-2015, 02:50 PM
Have you picked any potential names for critters you'll get to name? Something along the lines of "Bruceilla" or "Bilgeitacia"?

Heh..."name bagging" doesn't get you much respect from the academics. And one thing an amateur needs, if he's to get anything done, is a bit of respect. ;)

Of course, there are ways a determined narcissist can make his mark. Consider rogue herpetologist Raymond Hoser (https://en.wikipedia.org/wiki/Raymond_Hoser), who has made himself notorious by flooding the field with hundreds of unnecessary new taxon names. He's named groups and organisms after members of his own family, as well as his dogs. He publishes these in a "journal" he owns, without much regard for good taxonomic practice. Under the rules of the ICZN (the governing body for zoological nomenclature) what he's doing is more or less legit, but he's made a lot of enemies in the snake world. :D The Tetrapod Zoology blogger at SciAm has written a fairly unflattering piece about him: Taxonomic Vandalism and the Raymond Hoser Problem. (http://blogs.scientificamerican.com/tetrapod-zoology/2013/06/20/taxonomic-vandalism-and-raymond-hoser/)

02-24-2015, 03:44 PM
Raymond took Madonna strategy.


Bruce Taylor
02-24-2015, 04:19 PM
Raymond took Madonna strategy.

:D :D Yup, you can't say "everybody loves Raymond," but all the herpetologists have heard of him.


Bruce Taylor
02-24-2015, 10:43 PM
Nor is "rapacious flagellate". At least, I don't think so. Colponema, say.



Crack that whip, baby. ;)