Hi Eddy:
The information you could provide is listed in the Elegance Coral Project Summary thread right below this one. It is also in the first two posts of this thread. thanks for the offer.
Project update:
Thanks to John Link's efforts, we are now, I believe, over the required initial funding requirements for this porject. I say this only tentatively, because I still have nowhere near the number of corals I need, and if the donated money must be used to purchase corals, we are below the study needs. However, I have had an onslaught of offers, and if everyone comes through with their promises, we should have enough. All that would remain is for me to acquire some directly from the exporters or the ocean, and we are in good shape.
I currently have eleven sick elegance corals all ready to be sent off to histology. I thought I would share a little preliminary finding on these specimens.
One of the things I do after fixing the coral tissue is decalcify the skeleton. You have to dissolve the carbonate in dilute buffered HCl so the polyps tissue can be sectioned. As this happens, you get to see all the organic material that is left in the skeleton. Many of the corals had quite a few small bivalves, probably Lithophaga, within the skeletons, but not all. One had a small, as yet, unidentified crustacean that is probably a pit crab, but is very odd looking.
The second interesting aspect is the amount of algal and fungal filaments in Catalaphyllia. This is perhaps expected given a relatively well bored, lightweight skeleton, especially one that is found buried in organically enriched sediments. All corals hae some amount of extraneous material within the skeleton. But these Catalaphyllia have a lot...way more than any other coral I have worked with. Also, these filaments are attached to and may be penetrating the tissue. I have to work fairly hard to carefully remove a lot of this material from the underside of the polyps where they were originally attached to the skeleton.
Penetration of fungal filaments has been found to occur in some corals, and though the coral usually walls them off, they are not alwas successful and the invasion of filaments does result in pathologic conditions in those corals studied. It will be interesting to see if, and to what extent, any algal or fungal invasion of tissue is occurring.
Most interesting, thus far, is the "white material." As you may be aware, many of these corals, especially in the later stages of decline, develop a white mucus like web or white film/paste along the tissue margins. I had previously said this may be a secondary or opportunistic colonization, and perhaps infection, and I posited that I suspected it would be Beggiatoa.
As it turns out, this material is far more developed on the underside of the polyps, and heavy deposits exists between the skeleton and the calicoblastic epithelium. It is not macroscopically visible in all samples, but is definitely in most samples. Some have this material visible within the polyp tissue, too, so it is clearly capable of being invasive. However, what role it plays is a total guess.
Friday, I did some smears and staining of this material, including gram stain. The material is homogenous and mostly homogenous filamentous debris with cells present. It is very white, and very "cheesy", but does not look white under the microscope. After the gram stain, and much of it tinted with safranin to the visible eye (indicating gram negative), I was almost counting my chickens that the white was from the reflected sulfur granules within the gram negative Beggiatoa.
What I saw, though, was very odd. The safranin really hadn't been taken up much, nor had the crytal violet. Very few things iin this material took the stain, and if anything, many of the filaments were staining blue, indicating gram positive if bacteria at all. But the blue stain was very light. It no longer really looked like bacterial mats or biofilms, or anything but a lot of debris.
I also had a resident microbiologist come up to take a look. We talked about it for awhile, and he said, "you know, this looks liek Actinomycetes more than anything, but there aren't any marine actinomyctes are there?" I said, no, I don;t think so, but I'll check." As it turns out, there are. And, they are being investigated for antimicrobial properties, found in marine sediments, resistant to high metal loads, etc.
Now, I'm not at all sure yet that's what these are. I have never seen marine actinomycetes before under a scope, and only learned of their existence 48 hours ago. Nor am I sure what role they migh tbe playing here, if that's what they are. Interestingly, these things are beneficial to plants in sediments. Are they also normally beneficial to corals that live in sediments by providing nutrients? Are they even Actinomycetes?
Lots to find out yet, but it was an interesting week with the elegance corals.