Twilight

The Twilight Zone of Testate Amoebae

This is an area to post interesting/intriguing/unknown things about testate amoebae or about the society. Please provide some general information about the organisms you post here (e.g. size, habitat).

Outstanding Mysteries

16/Jan/2017

Anna Šímová needs more details on the CRyptodifflugia she has found.

Images here: http://simova39.rajce.idnes.cz/Cryptodifflugia_pusilla/#Cryptodifflugia-pusilla-Kotelnice.jpg

19/Feb/2015

Tom Roland and Matt Amesbury have found the following microfossil in cores and surface samples from Polytrichum moss banks at various sites on the Antarctic Peninsula. They request your opinions!

ardley-unknown-joined.jpg

Tom brought an example of the sample to ISTA7 in Poznan but no one could reach a confident conclusion in the time available. Any further suggestions can be made as a forum post here.

02/Feb/2015

Manish Kumar, in India, has found the following and requests opinions. Length of shell is 64.6.

dl4.tif

Any suggestions can be made as a forum post here.

24/11/2014 unidentified Hyalosphenia

Hyalosphenia_unknown_zpse1dfd04f.jpgHyalosphenia_unknown_surface_zpsb161751b.jpg
details of the shell

Any ideas?

Best regards,
Eckhard

The forum discussion can be made here.

Solved Mysteries

01/10/2014 - unidentified cell from sphagnum fen

RW03_zps2ad94954.jpg

Does anybody have an idea where I should look to identify this cell. The plate scales remind me of Trinema.

The forum discussion can be made here.

Thanks and regards
Eckhard

28/06/2013 - Testate amoebae from Tierra del Fuego bogs by Simon van Bellen

flickr:9155900545
flickr:9155900533

This testate amoeba was found in multiple samples from peat bogs in Tierra del Fuego. It is about 60x40mm in size with one aperture. It has particles stuck to the aboral region pretty much like Heleopera, although there is no slit-like aperture, rather an irregular circle.

Would anyone know this taxon? Thank you.

The Forum thread corresponding to this query is in here

14/06/2012 - Testate amoebae or other micro-organism? From a peatland in China by Qin

QIN.jpg

Dear Colleagues, 
I found  a testate amoebae like species from  a peatland, For me, it looks like a Assulina sp. The size is small, but with a lot of individuals.
Please give your comments for this species taxomomy. I have tried to upload the picture to our website ISTA for many times, but it does not work.  Can some one help me to upload so that we can make the website accessible for the society.
Thanks a lot.
Best regards.

Yangmin Qin


The Forum thread corresponding to this query is in here

14/06/2012 - Microfossil from Tierra del Fuego, identification requested by Simon van Bellen

Analysing surface samples from Tierra del Fuego, I encountered this testate amoeba (?), restricted to "wetter" peat. I initially thought it would be Pseudodifflugia fascicularis, but after a closer look I started doubting.

Cannot fetch Flickr photo (id: 7186715079). The photo either does not exist, or is privateCannot fetch Flickr photo (id: 7371945096). The photo either does not exist, or is private

As you may see in the photos, the aperture is a bit a-typical, with a recurved collar, visible in the second picture. The outline is also somewhat different from what I have identified before as P. fascicularis. Size is about 30 micron.

22/11/2011- Mystery microfossil, identification requested by Richard Payne.

Hi folks, I was wondering if anyone could help identify these beasts. They are from a peatland mesocosm experiment and are very numerous. They are about 30-50 microns diameter and appear to be made of primarily organic xenosomes. In some (eg. pic 6) there appears to be an irregular-shaped aperture occupying much of a side. My first instinct was maybe Phryganella acropodia but these look odd to me. Firstly in some of them it is really hard to see any aperture at all (but these are in a plankton chamber so it's not easy to turn them over without sending everything flying). Secondly, some of them seem to have a weird sort of 'halo' rather than a clear edge to the test which looks a bit weird. What do you think? any ideas? I've already asked a few people and the general opinion has been 'maybe P. acropodia'.

Slide1.JPG
Slide2.JPG
Slide3.JPG

3/14/2011 - Nebela from British Columbia (Canada), identification requested by Edward Mitchell, mystery solved by describing a new species!

SOLUTION This amoeba was described as a new species: Nebela meisterfeldi n. sp. Heger et Mitchell, in honor of Dr. Ralf Meisterfeld, one of the most distinguished researchers in testate amoebae systematic and ecology in recognition for his contribution to this field.

See literature section: Kosakyan A, Heger TJ, Leander BS, Todorov M, Mitchell EAD, Lara E. 2012. COI Barcoding of Nebelid Testate Amoebae (Amoebozoa: Arcellinida): Extensive Cryptic Diversity and Redefinition of Family Hyalospheniidae Schultze. Protist 163(3): 415-434. doi: 10.1016/j.protis.2011.10.003

Original Request Thierry Heger found this Nebela species in British Columbia (Canada). We believe it is a new species as it does not match any described species we know.

If you have any suggestion, we can discuss about it in the Forum!

Nebela_sp_Light_Microscopy.jpgNebela_sp_SEM.jpg

12/13/2010 - Beast from Serra do Japi, identification requested by Dan Lahr, mystery solved by Yuri Mazei

SOLUTION Yuri Mazei has identified this amoeba as Difflugia nodosa. Taxon was originally described by Leidy as Difflugia pyriformis var. nodosa, and raised to species status by Ogden and Zivcovic 1983. You can check out page 355 of the Ogden and Zivcovic reference for SEMs of this beast which is freely available at BHL here!

Original request - I found about 8 of these amoebae some years ago in the beautiful Serra do Japi, located in my hometown Jundiaí. The Serra is one of the last remaining Atlantic Rainforest reserves. There is quite a deal of controversy whether it is primary or not.

In any case, I found this thing and did not know what to make of it. I originally thought it looked like a Pontigulasia, but the v-shape in the neck was not very clear. Then I thought it looked somewhat like the Difflugia pyriformis or Difflugia compressa portrayed by Leidy. Then when I went to the SEM and saw the cement (which seems Lesquereusia-like), I didn't know what to make of it.

I apologize for lack of scale bars, but the notebook with the information is somewhere back in Brazil. If I remember correctly, the test was big, something in the 300 micron range, perhaps more. I can't remember the type of habitat either, but it could've been puddles filled with decomposing leaves…

If you'd like to help me out with identifying this beast, we can discuss about it in the Forum!

unknown_japi.jpg
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License