Coral...what type?

[Michelle Sawicki Library]

I am pretty sure this is fossilized coral, but does anyone know what type? It was found in Jefferson County, MO. The closest creek I found a name to is Head's Creek.

 

[Michelle Sawicki Library]

 

[Michelle Sawicki Library]

[ynot]

Yes it is coral, others will give a better id than I can.

What is the size?

[Jeffrey P]

That's a very nice tabulate coral. Congratulations.

[TqB]

Agreed, a good favositid .

[FossilDAWG]

If you can provide a more precise locality or geological formation, we might be able to suggest possible more specific IDs.

 

Don

[Michelle Sawicki Library]

Head's Creek in Jefferson County, MO is the closest creek with a name. This is probably a branch of that creek. I would say it is about 8-10 inches length. Here is it next to a nickel.

[Pumpkinhead]

I think that is is a colonial rugose coral, like Columnaria

[FossilDAWG]

The locality seems to be close to the boundary between Ordovician and Mississippian bedrock.  If it is Mississippian, the fossil may be a Michelina.  If Ordovician, it could be a species of Foerstephyllum.  The irregular size of the corallites, and the lack of obvious septal ridges, seems more like Michelina to me.  Thin sections would be needed to definatively resolve the question.

 

By the way, Columnaria is an old name that used to applied to a number of Ordovician corals. However, it turned out that the type species of Columnaria is a Devonian coral from the Eifel region in Germany, and it differs markedly from Ordovician corals in internal structures, particularly in the presence of well developed dissepiments that are totally lacking in the Ordovician corals.  Accordingly, the name Foerstephyllum was proposed for the Ordovician species, and Columnaria has not been used for these species since the 1950s.

 

Don

[Sagebrush Steve]

45 minutes ago, FossilDAWG said:

By the way, Columnaria is an old name that used to applied to a number of Ordovician corals. However, it turned out that the type species of Columnaria is a Devonian coral from the Eifel region in Germany, and it differs markedly from Ordovician corals in internal structures, particularly in the presence of well developed dissepiments that are totally lacking in the Ordovician corals.  Accordingly, the name Foerstephyllum was proposed for the Ordovician species, and Columnaria has not been used for these species since the 1950s.

 

Don

Sounds like a good opportunity for you to update Wikipedia.  It currently says Columnaria lived from late Ordovician to late Devonian: https://en.m.wikipedia.org/wiki/Columnaria

[TqB]

6 hours ago, FossilDAWG said:

The locality seems to be close to the boundary between Ordovician and Mississippian bedrock.  If it is Mississippian, the fossil may be a Michelina.  If Ordovician, it could be a species of Foerstephyllum.  The irregular size of the corallites, and the lack of obvious septal ridges, seems more like Michelina to me.  Thin sections would be needed to definatively resolve the question.

 

By the way, Columnaria is an old name that used to applied to a number of Ordovician corals. However, it turned out that the type species of Columnaria is a Devonian coral from the Eifel region in Germany, and it differs markedly from Ordovician corals in internal structures, particularly in the presence of well developed dissepiments that are totally lacking in the Ordovician corals.  Accordingly, the name Foerstephyllum was proposed for the Ordovician species, and Columnaria has not been used for these species since the 1950s.

 

Don

 

I'm seeing clear septal ridges when it's blown up but that doesn't rule out a micheliniid. I agree that sections would be needed.

[minnbuckeye]

I am trying to educate myself about coral anatomy after reading the above posts. Came across this  for those of you interested in learning the terminology to coral anatomy.

 

 

You are here: Home / Terms / Septa

Septa

 

Vertical blades that sit inside the corallite cup are called septa (singular is septum).  The septa are separated from skeletal structures outside the corallite, by the corallite wall.  The septa are often distinctive and may be used to differentiate between genera.

Recognising septa and costae (singular: septum and costa) in all their forms is critical to coral identification.

Septa are vertical skeletal elements inside the corallite wall, and are contiguous with costae when they cross over the wall. Costae may run across the coenosteum between corallites and join with the septa of the next corallite - the genus Favia.

[Pumpkinhead]

On 4/20/2017 at 8:00 PM, FossilDAWG said:

The locality seems to be close to the boundary between Ordovician and Mississippian bedrock.  If it is Mississippian, the fossil may be a Michelina.  If Ordovician, it could be a species of Foerstephyllum.  The irregular size of the corallites, and the lack of obvious septal ridges, seems more like Michelina to me.  Thin sections would be needed to definatively resolve the question.

 

By the way, Columnaria is an old name that used to applied to a number of Ordovician corals. However, it turned out that the type species of Columnaria is a Devonian coral from the Eifel region in Germany, and it differs markedly from Ordovician corals in internal structures, particularly in the presence of well developed dissepiments that are totally lacking in the Ordovician corals.  Accordingly, the name Foerstephyllum was proposed for the Ordovician species, and Columnaria has not been used for these species since the 1950s.

 

Don

 

Thanks for the info, I didn't know that

[Archimedes]

This coral cannot be a Michelina type coral because of the ridges present along the corallite walls and I have never found a Michelina type coral that radiates from a central point like this one,

and this coral is very similar to descriptions of Foerstephyllum from the Ordovician