Bunch of Brachiopods to ID

[Misha]

Hello everyone!

I recently received a package from @connorp filled with wonderful brachiopods!

I am not exactly sure as to what the IDs for some of them are so I thought I would ask here Any help is greatly appreciated!

Thank you

 

1. Silica shale. These look like Atrypa sp. but I am not sure what species are present in this formation. 3 cm wide

2. Same formation. Stropheodonta? 2 cm wide

3. This is from the Ordovician Liberty Formation. Rhynchonellid not sure what genus or species 1.5 cm wide

4. Some kind of strophomenid from the Mifflin Member of the Platteville formation 1.5 cm wide

5. Same formation .5 cm wide

 

[Misha]

More pictures of #4

[Misha]

All of the following are from the Late Pennsylvanian LaSalle limestone in Illinois:

6. Linoproductus sp.? 3 cm wide

7. Composita sp.? The two brachiopods here are very different in size one is about 1 cm in length and the other is closer to 2

8. A spiriferid, I have never seen spiriferids from this location and have no idea what the ID could be, about 4 cm wide if you count the very top of the wing

 

[Misha]

Another from the liberty formation:

9. Zygospira modesta? Most are about .5 cm wide

 

[Thomas.Dodson]

I can help a bit with the Lasalle Limestone stuff having collected there while I was in Illinois. Linoproductus cora is the first. The Composita are Composita argentia. If I recall correctly the possible spiriferids known from this age in Illinois are Neospirifer dunbari, alatus, and cameratus. I found Spiriferids from the Oglesby Lasalle site but I wasn't confident in Identification with the material I had, although I was leaning alatus. I've mostly found dunbari from the other Lasalle exposures I collected in but I have collected alatus in from the overlying Patoka-Shelburn undivided. I think it might be alatus but I'd like to see more pictures.

[ClearLake]

That is a very nice group of brachiopods.

 

#1 looks like Pseudoatrypa, maybe P. devoniana

 

#2 is Strophodonta, not sure I could get a species from those pictures but S. demissa is fairly common from the Silica Shale

 

#3 is Lepidocyclus capax or was, but the genus has changed and I can’t remember the new name. Looked it up: Hisscobeccus

 

And yes, #9 is Zygospira modesta. 

 

@Tidgy's Dad is a good source for the others or if I goofed up something. 

 

[Tidgy's Dad]

Your tags mention only Penssylvanian and Ordovician but I guess you know that the Silica Shale is Mid Devonian? 

The two main atrypids found in the Silica are Atrypa reticularis and Pseudoatrypa devoniana. 

You may have one of each there, I can't tell for sure. Atrypa is rounder and has a slightly convex brachial valve while Psedoatrypa is more elongate and has a much higher, more convex brachial valve and flatter pedicle valve.

2. Stropheodonta demissa.

3. Could be Hiscobeccus capax or Lepidocyclus perlamellosum. I'm guessing the latter due to the clear growth lines despite some wear. 

4. Strophomena plattinensis. Probably. 

5. Dunno. I don't have this one, I don't think. Hesperorthis? 

6. Linoproductus "cora", though this is a bit of a bucket taxon, so it's probably something else even if not described properly yet.

7. Zygospira modesta. 

8. Composita argentia.

9. Maybe Neospirifer, or Spinocyrtia if not. 

 

[Misha]

@Thomas.Dodson @ClearLake @Tidgy's Dad

Thank you all very much for the help!

 

I didn't know about the distinction between Pseudoatrypa and Atrypa, by that description it appears that these ones are Pseudoatrypa, they have very flat pedicle valves and strongly inflated brachial valves.

[connorp]

5. Might also be Zygospira, there is at least one such species in the Platteville.

7. Yes, Composita. I call them Composita sp. I think there is a debate over whether the different Composita species are just morphotypes of one species, so I don't even try to assign specific names.

8. I call these Punctospirifer kentuckyensis, although I don't know if the specific name is correct.

[Misha]

Here are my final ones which are from the Ordovician.

10. Hesperothis tricenaria? I have seen these often from the Platteville formation but this is the first time I've tried to figure out an ID. I find their shape to be very interesting.

11. These aren't from this batch but thought I'd just include them in this topic as I've been wondering about this. Liberty formation, I know these are Strophomena but what's the species? or are there different species present in this formation? I've been calling them S. planumbona but I don't know that this is correct.

[Tidgy's Dad]

Both of your ids are correct.

The Hesperorthis look beautiful when prepped.

 

 

 

 

[Misha]

12 minutes ago, Tidgy's Dad said:

Both of your ids are correct.

The Hesperorthis look beautiful when prepped.

     

That is lovely!

I might try preparing mine eventually

[Tidgy's Dad]

1 hour ago, Misha said:

That is lovely!

I might try preparing mine eventually

It's easy! 

[connorp]

I've been playing around with an ultrasonic cleaner. Only $35. Works wonders on the Platteville and Liberty brachs in particular.

[Thomas.Dodson]

6 hours ago, connorp said:

8. I call these Punctospirifer kentuckyensis, although I don't know if the specific name is correct.

I've found Punctospirifer kentuckyensis in the Lasalle but they're easiest distinguished from the Neospirifers by the wavy chevron/puncture covered surface. I don't see that on his specimen. I'm leaning towards Neospirifer alatus but I'd still like to see more pictures.