Identification help please with microorganism

Thomas Ashcraft · Post by **Thomas Ashcraft** » Thu Aug 17, 2006 11:21 am

Image : movie extract 200x brightfield

At first I thought this might be a Euglena of some sort but now think it is an Amoeba. Found in a freshwater coy fish pond in New Mexico. It is very distinctive and I posted some short movies of its behaviour on the web at:

http://www.heliotown.com/Mystery_Organism1.html

Any help greatly appreciated.

Tom

Charles Krebs · Post by **Charles Krebs** » Thu Aug 17, 2006 2:47 pm

Tom...

fish pond in New Mexico

... hmmm...
How close to Roswell and Area-51?

Actually I think what you have here is a testate amoeba. Don't know an ID, possibly Euglypha of some type. Take a look at this page:

http://wslar.epfl.ch/mitchell/edward/te ... moebae.htm

Ken Ramos · Post by **Ken Ramos** » Thu Aug 17, 2006 6:22 pm

There is a couple on that link that look similar Charlie.

Very well could be a testate but the test in Toms image is quite clear looking, if it were a testate shouldn't there be the presence of epidpodia, clearly visible, attaching the amoeba to the test? A great image Tom.

I searched the Protist Information Server through all of the testates there but found not even a close match to this.

Charles Krebs · Post by **Charles Krebs** » Thu Aug 17, 2006 7:26 pm

Ken... if you look at the still picture at the bottom of the page Tom has linked to, there is a distinctive pattern that look very much like an amoeba test. Generally, I don't see epipodia that often in many of these. (Arcella is where I see them most often)

Ken Ramos · Post by **Ken Ramos** » Thu Aug 17, 2006 7:44 pm

Yeah, I see what you mean Charlie. I noticed that before but kind of dismissed it as may some sort of cell inclusion but your right, it does have the distinctive pattern of an amoeba test. I looked through the Protist Info Server but could not find a close resemblence to this one, maybe the Woods Hole site may have it.

Thomas Ashcraft · Post by **Thomas Ashcraft** » Fri Aug 18, 2006 7:23 am

Ken and Charlie,

Thanks for giving a direction to the search.

Citing : http://microbewiki.kenyon.edu/index.php/Euglyphids

"Euglyphida are unicellular organisms lacking flagella, cytosomes, and centrioles. They have silica scales; these are shaped like ovals. There are about 150 scales on each organism, making up a test (shell). These scales are formed by surface-excretion. Scales are held together with a sticky secretion called pseudochitin. This test is often transparent, and many are equipped with spines. The organism can retract into this case if it is disturbed or threatened. Euglyphida move and feed with filipodia."

So yes, I think this could be some sort of Euglyphid although I haven't found an image of one with a distinctly pointed posterior end as yet on the web.

These guys have a lot of interesting processes going on inside their tests and I think I will keep videoing them in detail when they appear in my scope.
Tom