Euplotes species - my first sighting so 2nd opinion welcomed

Bruce Williams · Post by **Bruce Williams** » Tue Nov 14, 2006 5:14 pm

Hi folks,

The first pic shows what I believe is a Stylonychia species. I have included it mainly to give scale to the ciliate in the second pic.. This pic shows a larger ciliate - certainly larger than the Stylonychia (assuming my identification of pic1 is correct). You can see a Stylonychia at the bottom right of pic2.

The ciliate in pic2 looks VERY flat when viewed edge on which made me think it may be a Euplotes species. From the original video I'm pretty sure it has 4 long caudal cirri which would also support identification as a Euplotes.

Pic1 is from 8 megapixel photo and Pic2 is still from 640X480 video (15fps).

Bruce

PIC1 (Stylonychia?)

PIC2 (Euplotes?) Note the smaller Stylonychia at bottom right.

Ken Ramos · Post by **Ken Ramos** » Wed Nov 15, 2006 4:09 am

Could be an euplote but then again I am not sure. Nice set of photographs though.

bernhardinho · Post by **bernhardinho** » Thu Nov 16, 2006 4:16 am

Hi Bruce,

this hypotrich stuff is very difficult, especially having a foto only (although they're very good.) The first one COULD be Stylonychia, but I can't exclude Oxytricha fallax completely . The second one COULD be Stylonychia mytilus which is about twice as big as St. pustulata. For an Euplotes it is way too large, I think.

Keep it up.

Bernhard

Bruce Williams · Post by **Bruce Williams** » Thu Nov 16, 2006 8:32 am

Hi Bernhard,

Thanks for input - inciteful as always.

Concerning pic1:
I have checked out my other photos and a video I have of this particular ciliate and you can clearly see the 3 long caudal cilli . That taken together with my eyepiece observation (compared to photos on the web) make me pretty confident on Stylonychia as the genus.

Concerning pic2 (what I thought was maybe a Euplotes):
I've had a look at some web pics of Stylonichia mytilus and again from the video and my own eyepiece observation I think probably not. I will try putting up a short video of this larger ciliate to see if that helps point to a positive identification.

Thanks again for your interest and help.

(oh by the way Bernhard, I have received your recommended reading on Rotifers Key to British Freshwater Planctonic Rotifera - absolutely super book - thanks for the tip)

Bruce

bernhardinho · Post by **bernhardinho** » Thu Nov 16, 2006 9:57 am

Bruce Williams wrote:

I've had a look at some web pics of Stylonichia mytilus and again from the video and my own eyepiece observation I think probably not.

Hi again,

where did you find these? A google image search just lead me to one (!) obscure russian site, with one(!) useless image. I've scanned a page from one of my ciliate books, have a look:

But a video would surely help to clarify this, because locomotion can also be quite tell-tale.

Bernhard

Bruce Williams · Post by **Bruce Williams** » Thu Nov 16, 2006 11:33 am

Hi Bernhard,

Thanks for posting the images they do seem to support identifying pic1 to the genus Stylonycia don't they.

Well there a a large number of websites with photos and videos of Stylonychia species and a quite few photos and videos of Euplotes but I assume you mean specifically Stylonychia mytilus:

http://protist.i.hosei.ac.jp/pdb/Images ... index.html

http://protist.i.hosei.ac.jp/pdb/Images ... lus_5.html

Bruce

Bruce Williams · Post by **Bruce Williams** » Thu Nov 16, 2006 11:40 am

Hi again Bernhard,

Here's the website where I saw the video:

http://internt.nhm.ac.uk/jdsml/research ... dex%3D1040

More Stylonychi videos from same source:

http://internt.nhm.ac.uk/jdsml/research ... st=gallery

Bruce

bernhardinho · Post by **bernhardinho** » Thu Nov 16, 2006 11:44 am

Oh yes, our good old japanese sports. Abbreviations aren't always useful, that's why google didn't find them. I agree on the first pic, but don't you think that looks pretty close to your second one?
http://protist.i.hosei.ac.jp/pdb/PCD1786/htmls/05.html

To my eyes anyway. But let's wait for the videos.

I hope I'm not being too persistent, but for me identifying is great fun and part of the game!!

Bernhard

Bruce Williams · Post by **Bruce Williams** » Thu Nov 16, 2006 12:05 pm

Hi Bernhard,

I'm with you 100% on the fun of identifying what we are looking at - so please persist as much as you like

And yes I do see your point on that particular pic.

Well here is the video, I'm afraid it's rather pixelated as the original video was at least a full stop under-exposed and brightening it, then converting to DivX resulted in an interesting (to me) video although certainly not an aesthetically pleasing result.

I should point out that this is a clip from a much longer and better quality .MOV video in which you can clearly see that there are 4 long cilli not 3 as the clip might suggest.

http://www.tal-handaq.co.uk/ciliate_lge.html

Bruce

bernhardinho · Post by **bernhardinho** » Thu Nov 16, 2006 12:28 pm

Hi Bruce,

well, the video sort of establishes my (personal) assumption. Please allow me to quote the description of another book (hope I get the translation right into understandable english:

" peristome protruding far to the left, size and shape very variable(!), ..., 3 long caudal cirri, 2 of the right hand transvers cirri overlapping the rear (caudal) end of the body."

The last fact would explain the 4th cirrus you're seeing. I can also spot the contractile vacuole right at the bottom of the adoral zone of membranelles wich matches nicely with the scheme above. The question remains: how variable is "very variable" as far as shape is concerned. As I said, hypotrichs can be quite a nuisance when it comes to giving an ID.

Bernhard

Bruce Williams · Post by **Bruce Williams** » Thu Nov 16, 2006 5:52 pm

Hi Bernhard,

Had to do a little sketch but I got there (I think).

BTW - if you haven't already done so, when you are looking at the following webpage click on the Google Image Search link to view some interesting images and get some useful links to other webpages (from the image URL).

http://protist.i.hosei.ac.jp/pdb/Images ... index.html

Bruce