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Hello all, 

 

I found this spiriferid brachiopod steinkern (Mediospirfer? Mucrospirifer?) during my last outing to Deep Springs Road, in Lebanon/Earlville, NY. 

It has 3 dimples in it, that are unusal to me.

 

picture_2019_12_11_13_29_52_186-1.jpg

 

 

picture_2019_12_11_13_8_9_657-2.jpg

 

I'm looking to get some opinions as to the cause here? Are they pathological ? Are they damage from predators?

Are they just the way the shell grew, due to proximity to something kind of spiny? Or are they artifacts of the fossilization process? 

 

Thank you in advance, for any replies.

 

@Shamalama  @Tidgy's Dad

 

 

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2 hours ago, Fossildude19 said:

Are they damage from predators?

I believe you are on to it with this proposal - teeth marks.  I have found multiple brachs and amminoids in the Finnis Shale (Penn.) in Jacksboro, Tx.   What I'd like to know is "Who is the predator?"  Your finds are Devonian in age, mine are Penn, yet they look very much alike.

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Judging from the muscle scars, your Brachiopod appears to be an internal cast. The dimples are more than likely where epibionts that grew with the test.

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2 hours ago, fossilcrazy said:

Judging from the muscle scars, your Brachiopod appears to be an internal cast. The dimples are more than likely where epibionts that grew with the test.

Thanks for your answer, John. 
Makes perfect sense.  

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See the following:

Causes of damage to brachiopods from the MiddlePennsylvanian Naco Formation, central Arizona, DAVID K. ELLIO'IT AND SUSANNE D. BOUNDS  Lethaia20:327-335   (Thanks @piranha) :)

Alexander, R. 1986a: Resistance to and repair of shell breakage induced by durophages in Late Ordovician brachiopods. Journal of Paleontology 60, 273-285.
Brunton, C. H. C. 1966: Predation and shell damage in a visean brachiopod fauna. Palaeontology 9, 35M59.Carter, R. M. 1968:

On the biology and palaeontology of some predators of bivalved Mollusca. Palaeogeography, Palaeoclimatology, Palaeoecology 4, 29-65.

Elliott, D. K. & Brew, D. C. In press: Cephalopod predationon a Desmoinesian brachiopod from the Naco Formation, Central Arizona. Journal of Paleontology.

Sarycheva, T. G. 1919: The study of damage to Carboniferous productoid shells. Trudy Paleontologicheskiy Institut 18, 280-292.

Hope this helps.;)

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Looks like @fossilcrazy has the best suggestion for the cause of those dimples. Since it is a cast, could those be "pearl" like areas where the brach was covering some irritant? I've not heard of that in brachs before but am just throwing out an idea.

 

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It's a good idea, thanks, Dave. 

I appreciate your input. It bears some further research, at least. :) 

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Here's a middle Devonian spirifer with attached Cornulites. These little devils may have left those marks.  

DSC05689.JPG

DSC05690.JPG

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Thanks for that, Mikey! 

That is entirely possible. 

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Fossildude19

Thank you, Adam. :)

I appreciate the link. 

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Manticocerasman

I noticed that hte left and right mark are at the same location on each side on the brach, it might have been a mark from an internal organ? (lophophore?) but I don't know much on brachiopod anatomy.

 

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  • 2 weeks later...
On 1/3/2020 at 4:32 AM, Manticocerasman said:

I noticed that hte left and right mark are at the same location on each side on the brach, it might have been a mark from an internal organ? (lophophore?) but I don't know much on brachiopod anatomy.

 

Thanks, Kevin. I don't think that is the case. Since this is a steinkern, I think the damage must have come from outside of the shell. 

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Judging from the muscle scars :default_clap2: I haven't ever found... Can you make more detail photo?  

image.png.3c67d35c5720083d306d083249280aa0.png

 

On 24.12.2019 at 12:46 AM, fossilcrazy said:

The dimples are more than likely where epibionts that grew with the test.

it looks like "blister" or sponges... see for more: YUANLIN SUN and ANDRZEJ BALIŃSKI Silicified Mississippian brachiopods from Muhua, southern China: Rhynchonellides, athyridides, spiriferides, spiriferinides, and terebratulides, 2011 ("blister", Fig. 4.)  Have you ever found them in original, not like print (trace fossils) ?

 

 

@fossilcrazy

Edited by Brach3
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  • 3 months later...

They also could be marks from a Coral that it got wedged between and continued to push into when opening up. When I use acid to remove corals from matrix, its amazing whats trapped in the corals that were all growing together. Packy

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