Urostyla?

RogelioMoreno · Post by **RogelioMoreno** » Mon Apr 16, 2012 5:36 pm

I think it is Urostyla; but I am not sure. It is difficult to ID this kind of specimen. I think maybe Bruce can help to ID it.

Objective: 20x/0.75

Rogelio

Bruce Taylor · Post by **Bruce Taylor** » Mon Apr 16, 2012 7:43 pm

It is certainly a Urostylid...but, as you know, the taxonomy of that group (Urostyla, Paraurostyla, Holosticha, Anteholosticha, Keronopsis, Pseudokeronopsis, etc. etc.) is a hairball.

I'm far from qualified to identify this guy. However...the ventral cirri do not suggest Urostyla, to me, and at ~175 µm the body is a bit on the small side for the species I know. I might suggest Anteholosticha, perhaps A. monilata. The size is exactly right, the ventral cilia look similar (to my eye, anyway), and the multiple macronucleus fits the picture.

Amazing images, once again (but you know that already, right?).

RogelioMoreno · Post by **RogelioMoreno** » Mon Apr 16, 2012 10:31 pm

Bruce,

Thank you very much for the info. I searched for info about the Anteholosticha and I think you are right about the ID.

Rogelio

discomorphella · Post by **discomorphella** » Mon Apr 16, 2012 11:35 pm

Hi Rogelio--

They are all beautiful but the second shot showing the lines of cirri is an amazing catch. How are you triggering your camera?

David

RogelioMoreno · Post by **RogelioMoreno** » Tue Apr 17, 2012 4:32 am

discomorphella wrote:Hi Rogelio--

They are all beautiful but the second shot showing the lines of cirri is an amazing catch. How are you triggering your camera?

David

That was very hard to do, from all my try to get that cirri only two pictures show them and from that two this was the best. To triggering the camera I use mirror lock up and the TE300 set to 80% light to the front port (where the camera is mounted) and 20% to the binocular head, I move the stage with my right hand (chasing the specimen) and with my left hand I change focus and fire the remote camera cable. I bought a foot switch device to fire the camera with my foot; but I have to do some change on it.

The foot switch is the following:
http://www.ebay.com/itm/Nikon-Microscop ... 41502e811e

The jack fit perfectly on my Cannon T3i; but as you know the Canon remote cable has two position (one middle and the other that fire the camera), the foot switch has the middle always on, I have to change the foot switch jack to one with 3 contacts (maybe I have to sacrify a Canon remote cable) to change that to off.

Thank you for your comments.

Rogelio

Bruce Taylor · Post by **Bruce Taylor** » Tue Apr 17, 2012 5:05 am

Rogelio, the arrangement of ventral cirri (those two strong parallel rows) actually suggests Paraholosticha, more than Anteholosticha. Last night, I ruled that out because Paraholoticha is defined as lacking transverse cirri (that little patch of cirri on the front surface of the cell, down at the tail end). Your specimen clearly has transverse cirri, so Paraholosticha seemed impossible.

Intriguingly, this morning I ran across an article by Arthur Borror describing Paraholosticha polychaeta, a species that does have transverse cirri (although they are rather short and undeveloped).

That makes me wonder if your specimen might be an undescribed Paraholosticha with transverse cirri (and, atypically, a multiple macronucleus).

RogelioMoreno · Post by **RogelioMoreno** » Tue Apr 17, 2012 4:38 pm

Bruce,

I was thinking we were in good way thinking about Anteholosticha (based on the picture here (checking again I see only 3 rows of cirri); but know that you mention the two strong parallel rows and Paraholosticha I am searching for info and pictures of Paraholosticha. What can you tell me about Keronopsis that I found here.

Thank you very much for your help.

Rogelio

Bruce Taylor · Post by **Bruce Taylor** » Tue Apr 17, 2012 7:23 pm

RogelioMoreno wrote:What can you tell me about Keronopsis that I found here.

It's part of the Urostyloid "hairball" I mentioned before.

Though it shares a family (Keronidae) with Paraholosticha, I passed over it, because the species I knew about were brick-red. However, colour doesn't seem to be a defining feature of the genus at all...so, it's definitely a candidate. In fact, it seems like a better match, than either Anteholosticha or Paraholosticha.

In brief: 2 rows of ventral cirri, transverse cirri present, caudal cirri absent. In other words, precisely what we see here!

Unfortunately, I couldn't find many good descriptions of particular species. Penard (who erected the genus) gives a very thorough description of K. helluo (Etudes sur les Infusoires, p. 238...available through Internet Archive). There are a couple more species descriptions on the NIES site, and a few pictures here and there (just one on Micro*scope!). I don't have Kahl's mighty text, unfortunately, nor do I have all of Helmut Berger's superb Monograph of the Urostyloidea...frustrating!

The conventional wisdom is that one needs silver staining to properly identify these guys. Your images are so superbly detailed that it ought to be possible for an experienced person (not me, alas!) to name it confidently.

RogelioMoreno · Post by **RogelioMoreno** » Wed Apr 18, 2012 4:55 am

Bruce,

Thank you very much for your answer.

Do you know any on-line source or book that can be used to try to ID this kind of specimen.

Rogelio

Bruce Taylor · Post by **Bruce Taylor** » Wed Apr 18, 2012 5:19 am

Rogelio, recent articles can be found and downloaded through Google Scholar ( http://scholar.google.ca/) . However, to get over the many pay walls, you will need a university library affiliation (a VPN connection provided by an academic institution). If you can arrange this, it's the very best resource, giving access to the latest research. Recent articles on an organism will have bibliographical materials pointing to the older work.

Older books (Ehrenberg, Muller, W Saville Kent, Cash and Wailes, Penard, etc.) are often available online through the Internet Archive: http://archive.org/index.php

The most useful online site I've found is the NIES protist identification resource:

http://www.nies.go.jp/chiiki1/protoz/identifi.htm

The interface is inelegant, but the database is vast and provides descriptions of most genera and many species.

David Patterson's Micro*scope is the best source for images, I think (Encyclopedia of Life, another Patterson project, is a close second). As you know, many of the organisms on amateur sites, YouTube, etc. are misidentified. On Micro*scope and EOL, the pictures have been posted by people who know what they are doing.

For ciliates, a handy starting place is W. Foissner's "Use-friendly guide': http://onlinelibrary.wiley.com/doi/10.1 ... x/abstract

I'll post other links as they occur to me.

RogelioMoreno · Post by **RogelioMoreno** » Thu Apr 19, 2012 5:00 am

Bruce,

Thank you for the references.

Rogelio