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Randyw

Nice!

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Fossilis Willis

Congratulations on your "Yeti" find. 

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Mike from North Queensland

Congrats its always to find that one specimen that eludes. 

 

 

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Ludwigia

Congratulations!

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Manticocerasman

nice, always great to find a fossil from the bucket list :)

 

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Bobby Rico

Great find congratulations. 

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FossilNerd

Congratulations! Nice one!

 

:yay-smiley-1:

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Doctor Mud

Nice one @K-boy Cachers!

I know that feeling - you know they have been found..... there has to be one here somewhere.

The long wait just makes the find so much sweeter!

How will you display it? You can get “micro-mount” display cases with a lens on top that magnifies the specimen inside.

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digit

Persistence pays off--always great fun to finally find an elusive fossil!

 

 

Cheers.

 

-Ken

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K-boy Cachers
19 hours ago, JohnJ said:

It is exciting to find a complete bucket list fossil!  

 

Given that you found this specimen in the lower Cretaceous formations of western Bell County, it is probably not Leptosalenia texana.  It is more likely to be Leptosalenia mexicana, or the less common Leptosalenia leanderensis.  Or course, an accurate identification would require careful cleaning and examination.  Congratulations.  :)

 

Thank you JohnJ. The guy that took my boys and me on a "mentoring" fossil trip a few years ago simply called them salenia. I was doing my best to ID it based off of the Texas field guide by Finsley and was mostly trying to make my match off the pictures. I didn't see the Leptosalenia leanderensis in there.

 

Also, would it make a difference if it were the walnut formation?  I'm going to go back to the geological map today to see if I can be more specific on the formation. I live in an area that seems to skirt the lines where both formations pop up. 

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K-boy Cachers

Thank you for the link and, the map confirmed that I had my formations wrong. I was in the Walnut. I get confused because the hill that is a couple hundred yards away shows on the map as Comanche Peak fm.

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Monica

What a sweet little urchin!  Congratulations on your fantastic find!!!

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K-boy Cachers
29 minutes ago, Monica said:

What a sweet little urchin!  Congratulations on your fantastic find!!!

As I was pondering what to title my post i considered calling it, "Did Someone Lose an Earring . . . . 90M Years Ago???"

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erose
On 8/13/2019 at 7:10 PM, K-boy Cachers said:

Thank you for the link and, the map confirmed that I had my formations wrong. I was in the Walnut. I get confused because the hill that is a couple hundred yards away shows on the map as Comanche Peak fm.

The Walnut and Comanche Peak can be confusing sometimes. The CP tends to be more resistant and have nodular bedding versus the softer and more regular layers of the Walnut. Fossils are pretty much the same with the exceptions being very specific ammonites.

 

Also, Just being able to make the identification to genus is pretty good. Most of our Texas  "Salenias" are now placed in the genus Leptosalenia. You need to clean it up, but JohnJ's suggestion of Leptosalenia mexicana would have been my first guess as well.

 

And I know I was quite excited to find my first Salenia. They are sweet little ornate urchins. And now that you have spotted one you may have the eye for many more.

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grandpa
11 hours ago, erose said:

The Walnut and Comanche Peak can be confusing sometimes.

True that! 

 

11 hours ago, erose said:

Fossils are pretty much the same with the exceptions being very specific ammonites.

Can you be more specific please, for my own edification.

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erose
36 minutes ago, grandpa said:

True that! 

 

Can you be more specific please, for my own edification.

Oh, I'm no expert on ammonite zones. But some ammonites are limited to fairly specific layers. If you want to know more about them there is a pretty good publication on Texas Cretaceous ammonites from the Houston Gem and Mineral Society's paleo division. 

 

But learning to recognize various index fossils can be very useful. 

 

 

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grandpa
4 hours ago, erose said:

But some ammonites are limited to fairly specific layers. If you want to know more about them there is a pretty good publication on Texas Cretaceous ammonites from the Houston Gem and Mineral Society's paleo division. 

Good advice, Eric. 

I went to the HGMS publication and looked at all ammonites listed in the Walnut, the Comanche Peak, and the Goodland fm. (for, as I'm sure you know, the Comanche Peak blends into the Goodland above comformally in N.Tx. and the fauna is so much the same that distinguishing whether in the Comanche Peak or Goodland is equally as problematic as discerning the Comanche Peak from the lower Walnut is in Central Texas).  What did I learn?  Well first, there has to be a better set of fauna to use as index fossils for these three formations!

 

The Walnut has 3 unique ammonites not found in the CP:  Engonoceras boehmi (undescribed - no known samples); Protengonoceras emarginatum (Rare, also appears in the Edwards) and Metengonoceras hilli  (Rare and unique to the Walnut - a great index fossil - if you can find one in the exposure you are hunting in.  I actually have an excellent specimen that I collected in the Bee Cave unit of the Walnut.  But I've hunted a number of Walnut exposures and certainly not all have any traces of this ammonite.)

 

If you are looking for ammonite index fossils for the CP, there are three common Oxys found in the CP that are not found in the Walnut.  (There are also 10 Oxy sp. that are common to both, so discerning down to the species level with confidence is essential.)  They are O. obscurum, O. powelli, and O. carbonarium.  All, however are also found in the Goodland and so are not useful to distinguishing between those two formations.

 

For ammonites unique to the CP and therefore truly index fossils for the layer, I find only two:  Engonoceras stolleyi (Rare) and Metengonoceras ambiguum (Few).  The HGMS book has no pictures of either of these specimens, so one must use the verbal description as a guide, should one be fortunate enough to find a specimen in the exposure of interest.

 

So, I'm not feeling too confident in using ammonites (combined with my "skill set") as the index fossil to distinguish between Walnut, Comanche Peak, and Goodland.  I think I will take the spirit of your advice and apply it to echinoids, bivalves, and gastropods as found in the HGMS books on those topics.  I have found that the oysters  Exogyra texana and Gryphaea marcoui are used to separate the Walnut from the Glen Rose (The Geology of Texas, Vol. 1 - Walnut fm.), maybe there is a similar flag for separating the Walnut from the CP. :shrug:

 

 

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DPS Ammonite
17 minutes ago, grandpa said:

 

The Walnut has 3 unique ammonites not found in the CP:  Engonoceras boehmi (undescribed - no known samples

I am confused. How can a named ammonite be undescribed and have no samples?

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grandpa
11 hours ago, DPS Ammonite said:

I am confused. How can a named ammonite be undescribed and have no samples?

 

So, the quick answer is "I don't know".  Further I must confess, "no known samples" is an possible overstatement made by my assumption.  (See below)

 

Here's what the HGMS publication on Texas Cretaceous Ammonites (P. 92) has to say:

Shape:  unknown

Size:  Unknown

Ornamentation:  Fossil listed by Adkins and Arick, 1930.

Suture:  Unknown

Group, Formation, Stage:  Fred., Walnut, Albian

Frequency:  Unknown

Occurrence:  Bell Co.

[Needless to say, the book offers no drawings of the species.]

 

So . . . from all of the "unknown"s I assumed there must be no samples available, otherwise this information would be "known".  I'm reasoning that Adkins and Arick had a specimen in 1930 when they named the species and that it has since been lost, apparently along with the description of the specimen, but I should have indicated that that was my conjecture.  Sorry for the confusion.  I'll be more specific/detailed in my writing in the future.

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DPS Ammonite

I think that Adkins and Arick just listed the ammonite without giving an illustration of it. Since I could not find an illustration of it, the genus may have changed.

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