Eocene solitary corals

[bigulica]

Hello guys, 

 

As a begginer in the world of fossil hunting, I would appreciate your help with identification of several coral specimens I have found  in the eocene era fossil site near the town of Vrgorac, Republic of Croatia.

 

My guess, at least for the first specimen (first 4 photos), is that it represent some kind of Pattalophyllia, whilst for the others I honestly have no idea.

 

Also, the last specimen (last 3 photos),  looks like some kind of horn coral, which is weird, considering the fact that they went extinct during Permian and especially because it was found in close proximity of other specimens ( maybe 20-30 meters) and not even a meter form the (possible) Pattalophyllia.

 

Thank you in advance. 

 

      

 

    

 

 

    

 

 

    

 

 

    

 

 

    

 

 

    

[FranzBernhard]

Nice, thanks for sharing! How were the supposed horn coral and the other specimens found (bedrock, debris, gravel...)?

@oyo, @HansTheLoser

Franz Bernhard

[bigulica]

Horn coral and Pattalophyllia, were found in the debris, while other specimens were found in the sand deposits located around that debris.

 

I have read a bit about geology of that area and I have found out that, due to the seismic activity, eocen strata changed places with older strata (jurrasic and cretaceus) and pushed it upwards.

 

So, that specific microlocation is made out of mixture of sedimentary rocks (in debris of whose I have found the Pattalophyllia and horn coral) and sand deposits.

 

I will provide some photos of that general area as soon as I get some time to do that.

Edited February 28, 2021 by bigulica
Lapsus calami

[oyo]

10 hours ago, bigulica said:

Also, the last specimen (last 3 photos),  looks like some kind of horn coral, which is weird, considering the fact that they went extinct during Permian and especially because it was found in close proximity of other specimens ( maybe 20-30 meters) and not even a meter form the (possible) Pattalophyllia.

"Horn coral" is a colloquial name for horn-shaped corals. It is usually used in primary corals but there are horn-shaped corals at any time, primary, secondary, tertiary and today.

As for your specimens, the first could be Pattalophyllia, as you call it, but it could be other things. A question about the specimen, how big is it?

Unfortunately I find it difficult to assure anything about most of your specimens except for the discoidal corals that you present, which I believe could be Funginellastraea. Although I warn you that a much more detailed study of the specimens would be necessary to be sure.

 

[Rockwood]

11 hours ago, bigulica said:

Also, the last specimen (last 3 photos),  looks like some kind of horn coral, which is weird, considering the fact that they went extinct during Permian and especially because it was found in close proximity of other specimens ( maybe 20-30 meters) and not even a meter form the (possible) Pattalophyllia.

 

Given the similarity in color and texture, and lack of any clear indications to the contrary, I think this most likely is an example of convergent evolution. 

It has been questioned that modern corals are even closely related to the Paleozoic forms. The shape however is thought to be an adaptation to living on soft, and somewhat unstable sea floor. 

[bigulica]

Here are some more photos, this time with scale.

 

Also, what kind of tests could give You more information about the specimens? Is there something I could do by myself? Maybe cleaning  them? 

 

    

 

 

    

 

 

    

 

 

    

 

 

    

[Rockwood]

@TqB 

[bigulica]

Also, @oyo I guess that the inner section of the coral will help.

 

Considering that I have found couple of broken (possible) Pattalophyllia, I am posting the photos of them as well (photos 2, 4, 5 and 6).

 

Hope this helps.

 

    

 

 

      

[Rockwood]

I think the pattern of septal insertion tends to be more evident, thus diagnostic in the tip of the cone if you have it.

[TqB]

@Rockwood Thanks for the tag but I don't know much about scleractinians.

[Rockwood]

26 minutes ago, TqB said:

@Rockwood Thanks for the tag but I don't know much about scleractinians.

Shal we take this to mean that you believe them to not be rugosans ?

[oyo]

4 hours ago, bigulica said:

Also, what kind of tests could give You more information about the specimens? Is there something I could do by myself? Maybe cleaning  them? 

Not really, I was referring to thin sections of the specimens or at least polished to observe microstructures.

 

4 hours ago, bigulica said:

What it had seemed to me. Too large for Eocene Pattalophyllia.
For those specimens I would investigate Perismilia bilobata or Leptomussa variabilis.

This fauna reminds me a lot of the one I find in an Eocene outcrop in the South Pyrenean basin composed mainly of ahermatypic corals like Funginellastraea, Perismilia, Leptomussa, Petrophylliella and some other ahermatipic corals.

 

1 hour ago, Rockwood said:

Shal we take this to mean that you believe them to not be rugosans ?

Not rugosans, for sure.

[TqB]

2 hours ago, Rockwood said:

Shal we take this to mean that you believe them to not be rugosans ?

Ah, I just read the whole post - I was going by the "Eocene" tag.  The three photos of the horn coral don't show anything diagnostic, but, if it's Eocene, it's scleractinian. As you say, the forms are convergent and the horn shape is present in both groups.

[oyo]

On 2/28/2021 at 5:00 PM, oyo said:

This fauna reminds me a lot of the one I find in an Eocene outcrop in the South Pyrenean basin composed mainly of ahermatypic corals like Funginellastraea, Perismilia, Leptomussa, Petrophylliella and some other ahermatipic corals.

...... and some other ahermatipic corals like Leptophyllia dubravitzensis Oppenheim ,1912.

I knew I had seen this before.

On 2/28/2021 at 12:01 PM, bigulica said:

 

 

On 2/28/2021 at 12:01 PM, bigulica said:

And that is exactly what the literature reports for these specimens. Leptophyllia dubravitzensis Oppenheim ,1912. No Pattalophyllia neither Leptomussa or Perismilia.

Very variable in shape and size, with those epitheca rings and those big granules on the costae.

Reference literature : Oppenheim P. 1912 Neue Beiträge zur Eocänfauna Bosniens. Beiträge zur Paläontologie und Geologie Österreich-Ungarns und des Orients.Mitteilungen des Paläontologischen und Geologischen Institutes der Universität Wien (1902-1915) Vol.25: 3, pág.:87-149 lám. 10 –17

[piranha]

This monograph has many figured specimens from this region:

 

Kolosváry, G. 1949
Dunántúli eocén-korallok. [The Eocene Corals of the Hungarian Transdanubian Province.] Földtani Közlöny, 79(5-8):141-242  LINK

[oyo]

Leptophyllia dubravitzensis Oppenheim 1912. Middle Eocene, Bartonian, South Pyrenean basin.

To compare with the Croatian specimens.

 

 

 

 

 

 

Comment that the generic Leptophyllia ascription for this material is only a bibliographic reference, adequate preparations and studies of  then would be necessary to confirm said ascription.

[HansTheLoser]

Corals cannot be given a name just looking from outside. They need to be cut and/or polished.

It would be the same when a doctor looks into your face and says "oh you have got a stomach problem".

[oyo]

46 minutes ago, HansTheLoser said:

Corals cannot be given a name just looking from outside.

This depends. It depends on how well the material is known and how characteristic it is.
In fact you do it, I've seen you do it. And I do it too and most of the time I get it right. I remember you Rhizangia brauni (Michelin, 1847) or Rhizangia brevissima (Deshayes, 1834). Also Astrocoenia numisma (Defrance, 1826) or the Ahrdorffia of the South Pyrenean Basin Eocene. To give you some examples.

[bigulica]

Thank you all for info you provided.

 

I have contacted paleonologist who is specialised in eocene epoch of this part of Croatia, and I will let you all know what exactly it is as soon as I get the answer.

[HansTheLoser]

@Bigulica Who is that? As far I know Eocene coral research became complete extinct after Sylvie Barta-Calmus wrote her thesis on European Eocene corals in 1973. You cannot count Álvarez, this is not scientific.

 

@Oyo The number of genera that can be identified by merely "look at the surface" is very low, and less in solitary corals. Better do not try to simplify science.

[oyo]

20 hours ago, HansTheLoser said:

@Oyo The number of genera that can be identified by merely "look at the surface" is very low, and less in solitary corals.

 

On 3/4/2021 at 4:03 PM, oyo said:

Comment that the generic Leptophyllia ascription for this material is only a bibliographic reference, adequate preparations and studies of  then would be necessary to confirm said ascription.

 

On 2/28/2021 at 5:00 PM, oyo said:

I was referring to thin sections of the specimens or at least polished to observe microstructures.

I agree on the difficulty of identifying solitary corals with the naked eye, that's why I made these comments, I don't know if you've read them.

 

 

20 hours ago, HansTheLoser said:

@Oyo The number of genera that can be identified by merely "look at the surface" is very low

What I do not agree at all is with this statement of yours. As I have said previously, I believe that It depends on how well the material is known and how characteristic it is. I have already given you several examples and I could give you more but I do not think it is necessary or convenient since the positions of both are clear.

 

 

20 hours ago, HansTheLoser said:

Better do not try to simplify science.

And I don't agree with this either.
I think science, when it comes to corals, should try to attract more people. Simplifying might be a way.
Although taking into account that scientists cannot even unify criteria between the different ways of seeing this world, it is difficult to achieve this.

Edited March 22, 2021 by oyo