Pinna

[Rockwood]

This was found in north Texas Cretaceous. It's been suggested that it is the bivalve Pinna. I can't argue against it. Anyone care to give it a shot ?

[FranzBernhard]

In that pics it looks more like a rudist!

Franz Bernhard

[DPS Ammonite]

Is there actual shell material in there?

 

I can’t help compare this to possible trace fossils with ribs found in the post.

 

http://www.thefossilforum.com/index.php?/topic/121688-unknown-fossil-val-verde-tx-grayson-formation/&tab=comments#comment-1332183

 

Near microscopic photos might help sort this out.

 

 

Edited March 4, 2022 by DPS Ammonite

[Rockwood]

54 minutes ago, DPS Ammonite said:

Is there actual shell material in there?

If you look close there are a few scraps left here and there. The center looks like calcite crystals to me.

[Creek - Don]

I'm not sure whether that is a Pinna. Here is my Pinna bivalve found in Central Texas for comparison. 

Edited March 4, 2022 by Creek - Don

[Rockwood]

1 hour ago, FranzBernhard said:

In that pics it looks more like a rudist!

Franz Bernhard

If there were fenestra in it, would that be an indication ?

It's hard to say for sure, but there may have been.

[DPS Ammonite]

33 minutes ago, Rockwood said:

If there were fenestra in it, would that be an indication ?

It's hard to say for sure, but there may have been.

What are fenestra? I know that it means windows like those in bryozoa.

 

What formation are these from? What does the cross section look like?

 

If from the Austin Group, it looks slightly like a Durania austiniensis rudist. A cross section will help.

[Rockwood]

2 minutes ago, DPS Ammonite said:

What are fenestra? I know that it means windows like those in bryozoa.

Ya, that's what it means to me too.

I don't really care what it is enough to deal with the formation it's from.

I'm afraid it's too fragile to get a sectional view with what I have available for tools.

[JohnJ]

3 hours ago, FranzBernhard said:

In that pics it looks more like a rudist!

Franz Bernhard

 

I agree.  This looks more like an eroded Durania or Sauvagesia sp. rudist.  

[Lone Hunter]

If it helps it was found in the Goodland formation Lake Worth.

[JohnJ]

1 hour ago, Lone Hunter said:

If it helps it was found in the Goodland formation Lake Worth.

 

Ahh...it does help.  So does looking at the size...

 

It may be a Parasmilia sp. coral.

Edited March 4, 2022 by JohnJ
Spelling

[Rockwood]

23 minutes ago, JohnJ said:

It may be a Parasimilia sp. coral.

There you go. I think that's it. I found a different coral there that was pure calcite crystals on the inside.

[oyo]

51 minutes ago, JohnJ said:

 

Ahh...it does help.  So does looking at the size...

 

It may be a Parasimilia sp. coral.

Perhaps you mean Parasmilia?

Edited March 4, 2022 by oyo

[JohnJ]

4 minutes ago, oyo said:

Perhaps you mean Parasmilia?

 

Indeed!  There is a typo on the photo in Finsley's book that I used as a reference. (Edit made above.) 

[Rockwood]

  Oh oh. I just realized what a speed bump this could be in the identification of horn corals.

[oyo]

8 minutes ago, Rockwood said:

  Oh oh. I just realized what a speed bump this could be in the identification of horn corals.

It would actually be a great advance. A new genus is always an important discovery for science.

[Rockwood]

31 minutes ago, oyo said:

new genus

I was thinking rugose/scleractinian.

I tend to leave genus to those with a bit more genius. 

[FranzBernhard]

10 hours ago, Rockwood said:

If there were fenestra in it, would that be an indication

In short: No.

But the mystery has already been solved, it seems. Great - a coral!

Franz Bernhard

[oyo]

8 hours ago, Rockwood said:

I was thinking rugose/scleractinian.

I tend to leave genus to those with a bit more genius. 

Man, if you talk about Cretaceous, rugose coral it's automatically ruled out.
You don't need any genius for that.

Edited March 5, 2022 by oyo

[Rockwood]

2 hours ago, oyo said:

Man, if you talk about Cretaceous, rugose coral it's automatically ruled out.
You don't need any genius for that.

True, but I don't believe in IDs based on where something was found. It's a fine short cut, but sort of cheating in reality.

[oyo]

50 minutes ago, Rockwood said:

True, but I don't believe in IDs based on where something was found. It's a fine short cut, but sort of cheating in reality.

You can believe what you want but knowledge of the correct stratigraphy is essential for an identification. In no case is it a shortcut, it is a fundamental necessity. There's something called stratigraphic range, it's a scientific thing, not a shortcut.
In the same way that knowing the exact location of the finds is equally essential for correct identification.
For this reason, all these data are recorded in scientific works.
Greetings from the scientific side of the moon.

[Rockwood]

1 hour ago, oyo said:

You can believe what you want

What it is will forever be distinct from where it is. That is my belief.

[Rockwood]

I'll even go a step further and say that when anyone believes that rugose coral can't be found above the Permian they are outside the bounds of science.

[FranzBernhard]

1 hour ago, Rockwood said:

I'll even go a step further and say that when anyone believes that rugose coral can't be found above the Permian they are outside the bounds of science.

Well, after 200 years of research, rugosa are simply not known from strata above the Permian. That´s the status of the data at the moment. There can not be a proof for non-existence. Because there is no such thing like proof in science. There are only observations and theories in science. With many theories very, very well substantiated by observations.

In that way, I agree with your statement.

Franz Bernhard

[Kane]

Perhaps to be charitable, rugose coral fossils can be found above the Permian if they are reworked pre-Permian deposits (drift materials like cobbles loosened from strata) or other forms of transport.