Jump to content

Unusual Pennsylvanian Period Brachiopod


LanceH

Recommended Posts

Here's an unusual Pennsylvanian Period brachiopod I found recently. I have several more exactly like it. Has anyone found or seen one like it before? I can't find it anywhere in my literature or web searches.

post-11-1202004711_thumb.jpg

Link to comment
Share on other sites

Lance,

Please post a couple of different views of that brach. It certainly is unusual.

JKFoam

The Eocene is my favorite

Link to comment
Share on other sites

Lance:

THese brachiopods are definitely rhynchonellids (sperfamily Rhynchonellacaea), and are fairly common in the Pennsylvanian shales of Texas and Oklahoma. These have been identified previously as as Leiorhynchus rockymontana Marcou, 1858. I have found specimens of this brachiopod in the Wewoka Formation of Oklahoma, East Mountain Shale of Palo Pinto County, Finis Shale of Jack County and the Lake Bridgeport Shale of Wise County. The brachiopods have 3 plications on the fold and 2 plications on the sulcus. They are generally referred to the genus Wellerella as Wellerella osagensis (Swallow, 1880). Because these brachiopods are distinctly larger, more sharply angular in form and have a deep sinus, I prefer to keep my specimens as Leiorhynchus rather than refer them to Wellerella.

Link to comment
Share on other sites

They look just like the Pugnax rockymontana on plate 10, figure 14 of "Fauna of the Wewoka formation of Oklahoma". Is this an older synonym for Leiorhynchus rockymontana?

Anyways, thanks for the identification Mike! :D

Link to comment
Share on other sites

They look just like the Pugnax rockymontana on plate 10, figure 14 of "Fauna of the Wewoka formation of Oklahoma". Is this a synonym for the Leiorhynchus rockymontana?

Lance:

Pugnax was the old generic name applied to these rhynchonellids by Girty in USGS Bulletin, "Fauna of the Wewoka Foramtion of Oklahoma" in 1915. Dunbar and Condra in "Brachiopods of the Pennsylvanian System in Nebraska" (1932) differentiated Leiorhynchus from Pugnax due to the presence of different internal structures (median septum and small crural cavity), which are missing in Pugnax. Pugnax was a common rhynchonellid in the Devonian and Mississippian. Another brachiopod from the Triassic of Utah was referenced to Pugnax, but was later referred to Rhynchonella (Rhynchonella uta). Many of the species referred to Wellerella were originally described as Pugnax, ie, Pugnax osagensis Swallow, 1908.

Mike

Link to comment
Share on other sites

those are really neat brachiopods Lance,

What other fauna did you find? i have never really encountered much marine pennsylvanian fossils before....

"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

Link to comment
Share on other sites

those are really neat brachiopods Lance,

What other fauna did you find? i have never really encountered much marine pennsylvanian fossils before....

Here's some pics from the location and some of the other fossils: Feb. 2, 2008

Link to comment
Share on other sites

lance, those fossils and location are AWESOME! i would love to hunt there, those shark denticles are so cool, and the other fauna you collected got me drooling!

Thanks!

"Turn the fear of the unknown into the excitment of possibility!"


We dont stop playing because we grow old, we grow old because we stop playing.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...