I've never been too good at ID'ing these, which is embarrassing.
But here they are anyway.
The second image shows the colony "contracted", and it is easy to see the how the stalks wind into a tight spiral.
The third image is a close look at a couple of these "coils". The shallow DOF provides an interesting "optical section" with some clues as to the makeup of the stalk. The contractile spasmonome is easily seen, and you can see how the outer sheath "scrunches" together as the stalk contracts. I believe the rounded "spots" seen in the cytoplasm around the spasnomone are mitochondria. But I'll leave it to the experts
If this is of interest here a a couple excellent references:
http://jcs.biologists.org/cgi/reprint/10/1/95.pdf
http://jcb.rupress.org/cgi/reprint/56/2/559.pdf
Olympus 20/0.70 S Plan Apo, DIC, Canon 350D. Electronic flash.
Olympus 20/0.70 S Plan Apo, DIC, Canon 350D. Electronic flash.
Olympus 100/1.40 S Plan Apo, DIC, Canon 350D. Electronic flash.
Carchesium (or Zoothamnium?)..edited: 4th picture added
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- Charles Krebs
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Carchesium (or Zoothamnium?)..edited: 4th picture added
Last edited by Charles Krebs on Fri Nov 14, 2008 11:33 am, edited 1 time in total.
- Charles Krebs
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- Martin Kreutz
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- Location: Konstanz, Germany
Hi Charles
I would like to correct the ID of Jan (sorry, Jan)! I’m very sure that this is Carchesium polypinum and not Zoothamnium! The first hint is the shape of the colonie. The colonies of Zoothamnium are shaped like an inverted umbrella. Furthermore the zooids of Zoothamnium shows no striation of the pellicle (on you images a striation is clearly visible) and the stalks of Zoothamnoium are contractable in a zick-zack shape while the contracted stalk of Carchesium is spirally shaped. But the main feature to differ Zoothamnium from Carchesium is the central myoneme (or spasmoneme) in the stalk. The myoneme bundles of the zooids of Carchesium are disconnected from the central bundle while the myoneme bundles in Zoothamnium are continously branched at each junction to the zooids. In your first image the discontinued stalk of Carchesium is visible. Additionally I have attached a (12 years old) image from my collection for visualization of the discontinued stalk.
Yes, the “spots” covering the stalk are the mitochondria and your last posted image shows very impressive the separated myoneme bundles within the plasm of the zooid. You are near to a molecular view!
Thanks for the images, Charles
Martin
I would like to correct the ID of Jan (sorry, Jan)! I’m very sure that this is Carchesium polypinum and not Zoothamnium! The first hint is the shape of the colonie. The colonies of Zoothamnium are shaped like an inverted umbrella. Furthermore the zooids of Zoothamnium shows no striation of the pellicle (on you images a striation is clearly visible) and the stalks of Zoothamnoium are contractable in a zick-zack shape while the contracted stalk of Carchesium is spirally shaped. But the main feature to differ Zoothamnium from Carchesium is the central myoneme (or spasmoneme) in the stalk. The myoneme bundles of the zooids of Carchesium are disconnected from the central bundle while the myoneme bundles in Zoothamnium are continously branched at each junction to the zooids. In your first image the discontinued stalk of Carchesium is visible. Additionally I have attached a (12 years old) image from my collection for visualization of the discontinued stalk.
Yes, the “spots” covering the stalk are the mitochondria and your last posted image shows very impressive the separated myoneme bundles within the plasm of the zooid. You are near to a molecular view!
Thanks for the images, Charles
Martin
- Charles Krebs
- Posts: 5865
- Joined: Tue Aug 01, 2006 8:02 pm
- Location: Issaquah, WA USA
- Contact:
Charlie,
Top photo is absolutely amazing! I'd hang it on my wall any day of the week!
You're images are so consistently beautiful they nearly always bring tears
to my eyes (seriously!) But I shed tears easily over extraordinary performances of classical music as well...thank you for all of the wonderful
work that you share with us, as well is the information on technique!
Best wishes for the Thanksgiving Holiday.
Tom
Top photo is absolutely amazing! I'd hang it on my wall any day of the week!
You're images are so consistently beautiful they nearly always bring tears
to my eyes (seriously!) But I shed tears easily over extraordinary performances of classical music as well...thank you for all of the wonderful
work that you share with us, as well is the information on technique!
Best wishes for the Thanksgiving Holiday.
Tom