Filaments

[G.Alexander]

This table produces filaments at the part of the coral that is covering the substrate from time to time. I have observed this only happens if the coral is growing at those parts. The white patches in front on the rocks are all filaments.



Could it be a mechanism to “clean” the rock, killing periphyton on the rock which is encrusted from the coral in the next days ?

G.Alexander

[Aged Salt]

Alexander, great pix & a good question . Did you just stir up the substrate around the coral or your SB? Did you just feed C-V or other particle food? Is this coral near a soft coral? Alllelopathic causation? Thnx. Bob

[coralite]

The filaments you see are exactly that, acontia filaments. Acontia/mesentarial filaments are a part of the gastro-vascular cavity (GVC) of cnidarians. These filaments have a very high density of nematocysts and they can be extended through the oral opening or the GVC. In anemones these are used to further subdue ingested prey items and in our acroporas they are primarily used to "clean" the substrate it is encrusting on. For sps they are the equivalent of sweeper tentacles because they can be used to sting neighbours which are within ~1cm. These filaments cause the halo of clear substrate around the base of sps colonies and frags. The release of acontia filaments in parts other than the base can be a sign of stress, aggression towards a neighbour and occasionally, some specimens can keep these filaments extended in random parts of the colonies for unusual reasons.

The filaments in the right of your image look more or less like acontia filaments but the accumulation at the base is abnormal. With your developing mesophotography skills you should be able to get us a larger cleare view. At this angle I would suggest using some external light.

[G.Alexander]

Bob, nothing like this. This phenomena happens about every 3 weeks, followed by growth at this place. It only happens with this coral, just at the base where it encrusts the subtract.

Jake, thanks for your explanation. The event only last some hours. The first picture was taken 3 hours before the second one. I try to get another, better pictures next time I can observe it.



G.Alexander

[mesocosm]

Greetings All !

Alexander, great pix & a good question .

Indeed ! ...

Could it be a mechanism to “clean” the rock, killing periphyton on the rock which is encrusted from the coral in the next days ?

Definitely ... killing and capturing.


Here's an article folks may find to be relevant ...

Gastrodermal structure and feeding responses in the scleractinian Mycetophyllia reesi, a coral with novel digestive filaments.

Water M. Goldberg, Tissue & Cell, 2002, 34 (4) 246-261, Elsevier Science, Ltd.

PDF Full Text


BTW, for anyone wondering ...

Periphyton: Macroscopic (visible without a microscope) and microscopic (visible only with a microscope) algae (single- and multi-celled plants) that grow on or attach to rocks, logs, and aquatic plants. Periphyton, phytoplankton, and aquatic plants are the primary producers that convert nutrients into plant material by the process of photosynthesis.

Extracted From:
www.saludahydrorelicense.com/glossary.htm

[Ger]

Jake, what triggers those "events" as described by Alexander?

[mesocosm]

Greetings All !


Came across this today ...





Just trying to fill in the dataset ...

[coralite]

great Addition gary, Man I wonder what kind of digicam that guy was using to zoom in like that! Must of had like 100 megapixels.

[psam]

Dragging up quite an old one... Is this the same thing?

[G.Alexander]

Hi Sam



G.Alexander

[PocoLoco]

Hi Psam,

I don't think that is the same thing. Your pics look like mucous strings with some bubbles attached (something I have had in my tank lately).

[psam]

Yeah, that's what I was thinking at first, then I noticed how clean the centimeter or so of rock in front of the growing edge was and started wondering...

[G.Alexander]

From the picture it looks like any critter was active here like a snail or the Asterina sea stars.

http://www.zeovit.com/forums/showthread.php?t=11131

G.Alexander

[9866666]

Hi, I will update this theard, because I think it is connected to the topic.
So, the corals are showing filaments when is stressed, or nettle corals which are too close to them.
Friend of mine has a problem with zeovit stones. He changed the method about 3 months ago to zeovit. Now when he moves the zeofilter to move the stones in it, corals are showing their filaments. It's weird, in my tank I didn't observed that thing before. It looks like there were stressed or irritated. But why? Is it normal for someone who changes the method to zeovit with full tank of acroporas?
Here is example of those filaments. Photo shoot at blue light.