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dinogary

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Reply with quote  #201 
that is a unusual one . . like the felt coral Clap
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Reply with quote  #202 
Thanks guys!
Ryan - now there's an idea...
I'll section it soon.



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Reply with quote  #203 
Hi Tarquin,

Could it be dolomitisation with iron staining? Although if its a one off, I must admit it's unusual.

Very best wishes

Alistair
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Reply with quote  #204 
Hi Tarquin,

Meant to say that Alizarin Red S will not stain pure dolomite therefore the proportion of dolomite can be estimated by the amount of the specimen which is stained (or not) by the Alizarin.

Very best wishes

Alistair
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Reply with quote  #205 

Thanks, Alistair, you're probably right. It's full of voids too. Must get some Alizarin Red S, didn't know that!

Here it is sectioned - does appear to be vorticale (mostly 19 septa, but that's presumably fairly well down the corallites). It really does look like this under a microscope!

IMG_2113_ps_-_Copy.jpg 

IMG_2114_ps_Copy_1.jpg 

IMG_2116_ps_-_Copy.jpg 




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Reply with quote  #206 
Hi Guys,

I know this is a Carboniferous Corals forum, but I thought I would like to share this insignificant little coral with you. Insignificant it may appear, but it has huge implications for geology and taxonomy in particular. Why? Because this little coral is Kilbuchophyllia discoidea an Ordovician scleractiniamorph some 425 million years old. (It comes from Ordovician strata in the Scottish Borders). The problem is that Scleractinian (modern) corals did not appear in the geological record until the Middle Triassic some 225 million years ago. Another problem is that Rugose and Tabulate corals had calcite skeletons, whilst Scleactinian corals have aragonite skeletons. It also shows scleractinian septal insertion. So we have a 200million year time gap, a skeletal discontinuity and a taxonomic conundrum.. Who said corals were easy or uninteresting? The genus has raised some (heated) discussion in the palaeontological fraternity worldwide!!

The original species was discovered by Euan Clarkson and described by him and Colin Scrutton in 1991 and again by Scrutton in 1996 with the addition of K.clarksoni (a new species).
DSCF0254.jpg 

P.S. Many thanks for your help Tarquin!!!
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Reply with quote  #207 
That's fascinating, Adrian, I'd not come across that before - lovely specimen too.
I see that Clarkson includes a good summary of it in his Invertebrate Palaeontology textbook and the original paper is available here:

link

I like the interpretation of it as an early skeletalisation of the otherwise soft bodied scleractinian ancestors.

I came across an experiment recently that found that modern scleractinians start to secrete calcite when the water chemistry is right, so the calcite/aragonite difference between rugosa and sceractinia may not be a hard and fast one.

Talking of septal insertion, I've started to keep an eye open for heterocorals, haven't spotted any yet though.

Glad you sorted out picture posting, hope you've got some more!



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Reply with quote  #208 

that certainly is a interesting little coral..  it almost reminds me of one i have seen that prof clarkson collected from edinburgh area...


added another ordovician coral thats  from same age


 tarquin you will remember this one !


 unk_1111.jpg 


 

 

unk2.jpg 

 

 

 

unk3.jpg 

 

 

 

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Reply with quote  #209 



I remember, Gary, a nice little favositid we thought.

Here's a rather bloodshot  Lithostrotion maccoyanum, North Yorkshire coast erratic. A lot of recrystallisation again, would make pretty jewellery anyway...

IMG_2122_ps_-_Copy.jpg 

IMG_2123_ps_-_Copy.jpg 





Edited by TqB 2012-10-26 20:32:03

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Reply with quote  #210 
Hi Gary,

I presume from the Silurian inlier in the Pentlands? and certainly Favosites like.

Tarquin,

Thats interesting about Scleractinians secreting Calcite I hadn't come accross that research.

Heterocorals are interesting beasties. I came accross a Hexaphyllia in Treane Quarry Ayrshire almost a foot long! I left it in situ but took Pat Sutherland to see it as part of his paper

Sutherland and Mitchell : Distribution of the coelenterate order Heterocorallia in the Carboniferous of Great Britain : Rep. Ser. Inst. Geol. Sci. (Great Britain).

Best wishes

Alistair
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Reply with quote  #211 
it was so alistair,came from just above the small deerhope burn..

thats interesting about trearne hexaphyillia . there are quite a few species of coral from there,some of the preservation is very good, i have yet to collect a hexaphyllia from trearne or surrounding quarries, but my eyes will be looking for one
link is a similar one from about a mile  east of trearne



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Reply with quote  #212 
Alistair - many thanks for the reference, I've tracked down a copy to look at next week. That's an impressive Hexaphyllia, I won't rest until I've seen one!

Gary - good luck, bet you beat me to it. Good photo, you're obviously in the right area for them...



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Reply with quote  #213 
This Siphonodendron martini pebble from Redcar looked a little unusual, I think it's an algal limestone, reminds me of the Oxford Limestone on the Northumberland coast.

IMG_2131_-_Copy.JPG 

IMG_2127_ps_-_Copy.jpg 

IMG_2129_ps_-_Copy.jpg 



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Reply with quote  #214 
Nice specimen Tarquin. A longitudinal section would be nice!!!!

Most of my collection ended up in the National Museum in Edinburgh but I was working on offsetting in Koninckophyllum echinatum for a while. I'll see if I can still find some material to show here.

Keep producing these great specimens!!

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Reply with quote  #215 
Thanks, Alistair - longitudinal sections are harder! - but there's a bit that might work on this one.

I gather K. echinatum is a Scottish speciality (I see it occurs in the Dockra Limestone so is Trearne a possibility?) - be great to see some.



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Reply with quote  #216 
the dockra limestone is at trearne , and there is another site about 8 miles from there that the dockra washes out into the river ..
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Reply with quote  #217 
Here is a photograph (pre digital days!!!) of an acetate peel section of Koninckophyllum echinatum showing 13 off-sets. K. echinatum is a truly solitary coral and produced these off-sets presumably as a survival mechanism. I collected this specimen from the Petershill Limestone, Bathgate. This was peel No. 19 taken at 16.50mm and is registered in the National Museum collection as RMS Geol. 1982.56.2.

Tarquin,
I also found this type of off-setting in Scottish specimens of Dibunophyllum, so you are well placed to see if it also occurs in English specimens.

K. interruptum also produced offsets (3 or 4) which were paricidal and killed the parent!! However the offsets survived sometimes to adulthood themselves.

This area of coral research still needs some work.

Regards

Alistair
[attach:fileid=uploads/2489/konincko.jpg]
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Reply with quote  #218 
fantastic picture.... and great info,, is the entire specimen similar looking to Dibunophyllum or is it more caninia like ?
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Reply with quote  #219 
Thanks, Alistair, that's superb! - so not correct to describe it as phaceloid, as in Dorothy Hill?

I'm sure I have some specimens with offsets - I'll do some photos if they're any good.



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Reply with quote  #220 
Hi Gary,

Koninckophyllum is closest in appearance to Caninia although it is thought they inhabited different environments and Dibunophyllum tends to have an axial complex.

Tarquin,

Koninckophyllum is the classic example of why growth form cannot be used as a diagnostic principle!!! You can see that if the ƒ¢¢â€š¬…“budsƒ¢¢â€š¬‚ on my example reached maturity, you would have a phacelloid colony!! Indeed there is a wonderful example in the Hunterian Museum collection (collected by McNair but without a locality) that is a beautiful, large, phacelloid colony developed from a mature solitary K. echinatum!!! I would look forward to seeing any examples of offsetting you might have.

Incidentally my aged memory got it wrong again!!! On checking my field notes the Hexaphyllia was at Cunningham Baidland.

Best wishes

Alistair
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Reply with quote  #221 
Loving  your  work  on  those. 
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Reply with quote  #222 
danny1,

Thanks for your kind comments. Its about time corals staged a palaeontological comeback!!!

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Reply with quote  #223 


i agree alistair.. cunningham baidland  is that dalry ?

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Reply with quote  #224 
Yes Gary. That's the place!!

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Reply with quote  #225 
ah thanks,, its just  up the road from me Smile
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Reply with quote  #226 
I've been checking for offsets but don't have much that will show well without some prepping - I think this is Koninckophyllum interruptum, showing two new corallites growing from the outer edge of the parent calyx.

IMG_2148_copy_-_Copy.jpg 

IMG_2142_ps_-_Copy.jpg a



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Reply with quote  #227 


Interesting specimen Tarquin - are these offsets similar to the way some sponges when under environmental stress create small buds with all the required cells to create a viable sponge?
 
In those cases these buds can end up re-colonising the dead 'parents' skeletal structure (such as it is in sponges) - is this something that can be seen in fossil corals (wonders how you would tell) ?
 
Regards,
 
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Reply with quote  #228 
Ryan - I think it's a similar strategy. Normal colonial corals often increase by lateral budding with the original corallite surviving, which you can tell because it carried on growing.
With the solitary corals, it can be parricidal, as Alistair said - I presume one can tell this because the parent stops growing although the polyp might survive for a while.

I don't know if a new polyp could actually take over an empty calyx but it seems unlikely, the skeleton and soft parts are too much a single organism. (I might be talking rubbish though)





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Reply with quote  #229 
Hi Tarquin,

You are absolutely right. Your example shows paricidal offsetting and can occur in all species of Koninckophyllum. (Without a section I might hesitate to say which species this is, but I suspect you are correct again).
In my example the offsets originate on a small platform where the parent coral shrinks itself by about 4mm to accomodate the off-sets. This is typical of the off-setting I mentioned in Dibunophyllum. It is not easy to decide whether the parent shrinks to accommodte the offsets, or whether the off-sets occur as a response to a stress mechanism. I have found protocorallites on shell debris and other substrates but never (so far) on another coral although I see no reason to assume it might not happen.

I may still have some remains of prepped material which I will post if I find it.

Keep up the great work.

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Alistair
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Reply with quote  #230 
Here is another image of parricidal off-setting in Koninckophyllum. This is also from the Petershill Limstone, Bathgate.

DSCF0260.jpg 

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Reply with quote  #231 
Here are some more images of off-setting.

A Dibunophyllum etched in HCl showing the "ledges" with remnants of offsets.

DSCF0263.jpg 

Koninckophyllum showing parricidal offsetting.

DSCF0262.jpg 

And finally for Tarquin, a nice little Palaeacis from Aberlady Bay. I'm not so up to speed with Tabulates as we don't seem tyo have too many in the Scottish Carboniferous.

DSCF0266.jpg 

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Reply with quote  #232 
Many thanks for posting those, Alistair, they're fascinating and beautiful specimens. I'll see what I can do with my others as well as looking out for more.

Lovely Palaeacis, just the sort of thing I'm looking for!





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Reply with quote  #233 




alistair,,those specimens are fantastic , makes me want a visit back to petershill
i have a few specimens which turned out to be Koninckophyllum and were collected at petershill as well, not as good as those though
Edited by dinogary 2012-11-03 00:16:21

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Reply with quote  #234 


these two corals are both carboniferous,, im stumped for a id though,ant thoughts appreciated
1, from lugton quarry ayrshire
length is 45mm
11_01_22.JPEG 
 
 
 
 
 
2, from trearne quarry
length is 80mm,i have only photographed the end as sides of coral stll not prepped yet
 
11_01_21.JPEG 
 
11_01_19.JPEG 
 

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Reply with quote  #235 
Hi Gary,

I think they're both Michelinia (or similar) tabulate corals, very nice - I've got a couple from Morecambe Bay I'm going to post soon when I've done a section or two.



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Reply with quote  #236 
Hi Gary,

Very nice specimens!! I would agree with Tarquins diagnosis of Michelinia. The species is probably egertoni as this occurs frequently in the Ayrshire area, although of course without a section it is not possible to be certain. Petershill is an SSSI now so collection is only permitted from spoil! But keep collecting and we may resurrect corals yet!!

Very best wishes

Alistair

P.S. I'm sure some of you other guys must come across corals in your hunting. Lets have a look at them!!!
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Reply with quote  #237 


thanks for the ids...i think the second one would be long enough to section ,,
there a corner at petershill where corals are quite common from the scree and mud

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Reply with quote  #238 
Hi Gary,

Would that be the east shore of the old reservoire? If so, I did a fair amount of work there with Jerry Jamieson who did his Ph.D. thesis on the Petershill Formation. There are some superb Aulophyllum fungites from there (which is incidentally the type locality for this species).

There is also a sub species which occurs at this locality (Aulophyllum fungites pachyendothecum) which is distinguished from the main species by a very loose axial complex.

Very best wishes
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Reply with quote  #239 
Great show, old beans... No, but seriously. Great stuff, and a very interesting read 
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Reply with quote  #240 


exactly the spot alistair, i have collected very stright looking aulophyllum from there as well as ones with growths and bumps,, not visited petershill for a while but after winter im sure there will be some erosion

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Reply with quote  #241 
I was looking at an outcrop of the Frosterley Band in Weardale today and spotted this Aulophyllum apparently showing an offset with confluent septa.

(It's still there, this is an exposure that shouldn't be hammered).
DSC01752_-_ps_-_Copy.JPG 

DSC01754_-ps_-_Copy.JPG 

DSC01754_-_ps_-_Copy_2.JPG 




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Reply with quote  #242 
Hi Tarquin,

What a fascinating specimen!!! Firstly, I have never seen offsetting in Aulophyllum. I am trying to convince myself that this is indeed parent and off-set. The extension in the counter septal area of the parent would suggest that this is indeed an off-set. But then I wonder if this parental extension is merely an artefact of the angle of section!! Are the septa of both confluent? I'm not sure. And of ourse if this specimen is in an SSSI, then we will never know. Once again you have produced an exceptional specimen!!

Very best wishes

Alistair
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Reply with quote  #243 
Thanks very much for your comments, Alistair! The septa are definitely continuous so I'm wondering if it's a fluke section across one highly curved specimen.

The site isn't actually an SSSI, or even a RIGS as far as I know (anyone know if there's a list for Co. Durham?); it's a beautiful outcrop though and it would be a shame to damage it but perhaps justifiable for something significant. Be hard to get out though!



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Reply with quote  #244 
Hi Tarquin,

Curvature hadn't occured to me, but is a distinct possibility as the orientation of both sections is correct. It would still require an unusual growth form though - Maximum growth on the fossular side with no growth on the counter side?

Keep up the great work

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Reply with quote  #245 
Spotted this one in an aquarium on Sunday and thought of this thread :)






 

coralsplit.jpg 

coralsplitcloseup.jpg  

 

 

 

Regards,

 

Ryan

 
Edited by ryanc 2012-11-06 20:46:04
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Reply with quote  #246 
vbbbn.jpg 
 

found this large block of coral in ayrshire last week

 

 Diphyphyllum

 

thanks for help with id   tqb 

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Reply with quote  #247 
Hi Guys,

Here is an old print of a sectioned Koninckophyllum echinatum colony where the parent calyxes have become filled with sediment resulting in off-setting.

[attach:fileid=uploads/2489/koninck.jpg]
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Reply with quote  #248 


thats a fantastic  view of the colony,,is this a bathgate  specimen as well?

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Reply with quote  #249 
That's beautiful, Alistair - is it certain that the sediment infill caused the offsetting or could it be after the parent polyp died?

(More specimens to come soon - just need to finish a few off...)



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Reply with quote  #250 
Hi Gary,

This colony came from the Wairdlaw Limestone which s part of the Petershill Formation and lies north east of the Sivermine Quarry at Bathgate.

Tarquin,

We made a series of horizontal sections of one of the corallites, starting above the calyx and moving down to below the last secreted tabulae. We found increasing levels of sediment in the septal grooves and concluded that the corallite could no longer cope with the sediment influx and therefore produced these paricidal offsets as a survival mechanism. The offsets ocurred about the samne level of maturity throughout the colony, therefore supporting the idea of catastrophic sediment influx.

Very best wishes

Alistair
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