Pathological Brachiopods!

[Mediospirifer]

After washing some matrix from the site where I found the previous brachiopods (collected the same day) and sieving out the large pieces, I have a few more pathologicals and holed specimens. I'll post the more interesting ones here.

The question was raised as to whether the holes were the result of predation or burrowing. I think this piece and the next one answer that!

Hash plate:

Side view of hole:

If you look closely at the side view of the hole, there are two clearly visible pierced valves, with a third (thinner) valve at the bottom. The hole clearly pierces all three. We have a burrow!

I love being able to find evidence to settle a question.

[Mediospirifer]

Here's another hash plate, with a hole piercing two valves:

It's a little hard to see in the photo, but the brachiopod valve at lower left in the first photo does extend partway past the hole, and is pierced. If I were to remove some matrix it would be more visible. More evidence of burrowing!

I'll post one more brachiopod, just because it's cool.

[Mediospirifer]

Cincinnetina meeki, pathological valve with hole:

There's also a slot cut through the valve in the middle. I suspect that's a smaller, horizontal burrow trace, as the shell is not cracked at all in that area.

The things you can find when you collect a random sample and look at it closely!

[IonRocks]

Here's mine! (I think)

I have absolutely no info on it so that's it.

[Mediospirifer]

Interesting piece! Too bad you don't have any information on it.

I wish I knew more about what causes the overlap pathologies in some of my brachiopods. I wonder if it was a burrow through the edge of a living specimen, throwing the growth off? Whatever the cause, it affects at least two different species in the same way. Someone would have to dissect or X-ray a pathological valve to see (if it can be interpreted at all), and I'm not equipped to do that.

[Mediospirifer]

I need to correct some misidentifications.

A couple of days ago I took my brachiopods to the Ohio State University Geological Museum in Orton Hall to see if anyone was interested in looking at them. I was in luck: an Ordovician brachiopod specialist, David Wright, happened to be in and was quite intrigued with what I showed him. He doesn't know what caused the overlap pathologies, but he did know about my specimen at #12 with the odd growth rings. Apparently, this happens when environmental conditions stunt the growth of a brachiopod, making one ring shorter than the rest. My brach probably experienced several years of hard conditions, resulting in a very pronounced set of shortened rings.

David also told me that my brachs are all Glyptorthis insculpta, not Cincinnetina or Dalmanella. He also told me that all Dalmanella species have been lumped into the genus Cincinnetina, which was previously split off from Dalmanella! And before that, the genus was known as Oniella. There seems to be an ongoing discussion about what to call that genus.

The identifying characteristic to recognize Glyptorthis from Cincinnetina is the subtle horizontal ridges and more obvious growth rings. Now I'll get them labeled correctly!

I donated the specimen at #3 (with two overlaps) and a few others that David was particularly interested in, which I don't have photographs of. We'll see what can be learned from them!

Merry Christmas!

[Mediospirifer]

I have another update for this post.

While I was on vacation in Ohio, I also showed my brachiopods to Mark Wilson at the College of Wooster, in Wooster, OH. He found them interesting, and gave me a copy of a paper he'd seen that was relevant:

Richard R. Alexander, "Resistance To and Repair Of Shell Breakage Induced by Durophages in Late Ordovician Brachiopods" J. Paleontology, vol. 60 pp. 273-285 (1986)

The paper describes four types of healed shell damage, and discusses the frequency of such damage among nine different brachiopod species, grouped by similar shell morphologies. My specimens have the type he calls a 'cleft', and his chart indicates that he found clefts in 4% of the Onniella meeki (now called Cincinnetina meeki) specimens he examined (6 out of 150). Glyptorthis insculpta wasn't mentioned in the paper, but probably would show similar frequency to Cincinnetina.

The paper also discussed likely causes for the damages, and concluded that all four types of shell damage were likely due to failed predation by nautiloids. The author based this on the frequency of predator types in the fossil record, feeding styles, and one brachiopod specimen with an imbedded, healed-over inclusion that resembles part of a nautiloid beak. So, the brachiopod at #3 was nibbled twice by nautiloids, and survived both times! I don't know whether to call that critter lucky or unlucky...

It's an interesting read. My summary: Brachiopod bed nibbled by nautiloids, survivors scarred.

[Brach3]

The shells repairs are interesting... 

Some breakages are situated along the growth lines and have the form of long, irregular fractures. This suggests that the attack took place on what was at that moment the edge of the shell. In recent day it's associated with crustaceans or carnivorous gastropods or effects of the storm.

 

Do you have brachiopods with shells repair after drill-hole injury for evidence of biotic interactions?

 

It's growth lines and growth ledge because was growth halts / bad conditions (muddy water, abiotic factors, often crowded condition and etc).

 

On 11.09.2015 at 9:05 AM, Mediospirifer said:

(below the encrusting smaller brachiopod)

It's not Inarticulata (Brachiopoda). On my opinion it/s the same brachiopod but young. But it's not matter because this shell repairs are the most interesting. 

 

Shell breakage made by predator allows the brachiopod to continue growth, though a deformation of the shell indicates that epithelial cells have been seriously damaged in that area of the mantle. We cant see scars under the young brachiopod but I think there is a very serious damage. For more see Richard R. Alexander, Resistance to and Repair of Shell Breakage Induced by Durophages in Late Ordovician Brachiopods, 1986 (there are all your repairs).

 

Cephalopod Predation in Ordovic + from D3:

 

If you have singles valves (shells) then you can find epiazons from other side (inside the valve). See for more: 

Edited January 12, 2020 by Brach3

[Tidgy's Dad]

Very interesting thread indeed. 

I must check out my brachs and see if i have any pathological specimens. 

One little note is that I don't think all of the Cincinnatian Dalmanella have been moved to Cincinnetina, a couple, including what was Dalmanella emacerata have been moved to the genus Heterorthina. 

[Brach3]

On 11.09.2015 at 3:17 PM, Shamalama said:

This is a specimen of Paraspirifer bownockeri from the Silica Shale (Givetian stage of the Devonian) of Ohio.

 

unexpectedly (suddenly)... I've been writing the personal letters to all user here to find fossils (Brachiopods+Epizoans) from Ohio or Michigan or N.Y. (Silica Formation + Devonian)... because I've wanted to find photos (Spiriferida + Cornulites sp.)... and it turned out, but they (photos) are in the Diane's discussion )))  Shamalama, can you great topic / discussion in the "your new discussion" (your specimens of Paraspirifer bownockeri from the Silica Shale)? I'll write there comment + examples. If you will do please send me a link (I don't understand how to find fossils here  in discussions).

Edited January 12, 2020 by Brach3

[Mediospirifer]

18 hours ago, Brach3 said:

Some breakages are situated along the growth lines and have the form of long, irregular fractures. This suggests that the attack took place on what was at that moment the edge of the shell. In recent day it's associated with crustaceans or carnivorous gastropods or effects of the storm.

 

Yes. This was a cut into the valves from the edge when the animal was much smaller. The paper by R. Alexander suggests that the predator was a nautiloid.

 

18 hours ago, Brach3 said:

Do you have brachiopods with shells repair after drill-hole injury for evidence of biotic interactions?

 

No, all of my bored shells could have been drilled after the animal's death. 

 

18 hours ago, Brach3 said:

It's growth lines and growth ledge because was growth halts / bad conditions (muddy water, abiotic factors, often crowded condition and etc).

 

That matches what Dr. Wright told me when I showed him my specimens. Those specimens are impressive!

 

18 hours ago, Brach3 said:

It's not Inarticulata (Brachiopoda). On my opinion it/s the same brachiopod but young. But it's not matter because this shell repairs are the most interesting. 

 

Shell breakage made by predator allows the brachiopod to continue growth, though a deformation of the shell indicates that epithelial cells have been seriously damaged in that area of the mantle. We cant see scars under the young brachiopod but I think there is a very serious damage. For more see Richard R. Alexander, Resistance to and Repair of Shell Breakage Induced by Durophages in Late Ordovician Brachiopods, 1986 (there are all your repairs).

 

I agree with your identification of the smaller shell. I probably should have referred to it as stacked or tiled rather than encrusting. I did not mean to imply that the smaller specimen was an inarticulate species.

 

I have read that paper. Of the four types of scars he describes, I've found scallops and clefts. I may also have some divots, but the difference between clefts and divots is subtle enough that I'm not certain of the classification of some of the marks. I think of all of them as clefts.

 

I have a number of other scarred brachiopods (some with quite extreme damage). Here's one I found last June with several scars:

 

 

This one has four obvious bite marks that may have been inflicted at the same time. The predator may have tried to nibble a few times before giving up. The bites appear to have been made at the beginning of an interrupted growth sequence, and the formation of a growth ledge. Possible the stress of healing from multiple bites slowed the brachiopod's growth. There are also two scars that are not associated with the growth ledge (one just left of the midline, the other at upper left just inward from the uppermost scar). I think they were inflicted and healed earlier, possibly but not necessarily from the same attack. This is my specimen with the most bites.

 

19 hours ago, Brach3 said:

If you have singles valves (shells) then you can find epiazons from other side (inside the valve). See for more: 

 

I've never seen any like that! I do have a few specimens that have extra lumps on the interior surface that are fully coated with shell material. I'll have to look for such specimens.

 

18 hours ago, Brach3 said:

unexpectedly (suddenly)... I've been writing the personal letters to all user here to find fossils (Brachiopods+Epizoans) from Ohio or Michigan or N.Y. (Silica Formation + Devonian)... because I've wanted to find photos (Spiriferida + Cornulites sp.)... and it turned out, but they (photos) are in the Diane's discussion )))  Shamalama, can you great topic / discussion in the "your new discussion" (your specimens of Paraspirifer bownockeri from the Silica Shale)? I'll write there comment + examples. If you will do please send me a link (I don't understand how to find fossils here  in discussions).

 

I'm glad I could help you find what you wanted! 

 

To get another TFF member's attention, use the "@" symbol. @Shamalama

 

And to search the Forum for a particular term or phrase, type the words into the Search box at the upper right of the Forum banner. For example:

 

 

The red circle marks the box, and the red arrow indicates the button to click to search for that term. I recommend searching for "epizoan", "epibiont", or "encrust" to find posts.

 

Good luck! 

 

[Brach3]

On 13.01.2020 at 10:21 AM, Mediospirifer said:

Of the four types of scars he describes

Unfortunately, many scientists only describe scars, but do not try to interpret them!  ... because such assumptions are the most gratuitous work.

And if your have bite's scars you have to go to the other scientists... - how to embrace the vast. Sometimes we say: it's biotic organism or an abiotic object cannot be discerned + "repair of abiotic breakage during the life of the brachiopod cannot be ruled out (Sarycheva, 1949; Alexander, 1981)" see personal letter for articles (paper).  

 

On 13.01.2020 at 10:21 AM, Mediospirifer said:

I've never seen any like that! I do have a few specimens that have extra lumps on the interior surface that are fully coated with shell material. I'll have to look for such specimens.

And please see epizoans (epibionts) like brachiopods there (inside) too

For more see 2 PDF: An unusual brachiopod assemblage in a Late Jurassic (Kimmeridgian) stromatactis mud-mound of the Eastern Carpathians (Ha˘ghimas¸ Mountains), Romania, 2010 and PDF First report of brachiopod–brachiopod endoparasitism, 2010 = It'll be like an atomic bomb!!! 

 

 

№1 и №2 it looks like scratch / scrape (not scar). 

 

We have defined such scratches / scrapes like fish bites.  These brachiopods and fish jaw are from one place! We have scratches / scrapes on the both valves. And the distance between the teeth is the same as the distance between the scratches 

 

 

BUT if we have only 1 scratch / scrape then it couldn't be a fish with one tooth

 

 

--- If Cephalopod Predation then ---

 

Then we need to see the other side because ALWAYS we have scars from both sides of the brachiopod (on a par / on a level)

 

We don't know the Cephalopod's jaws from Orbovic and Devon, but know Jurassic jaws

 

 

And we have similar injuries (from one side of brachiopod we have puncture / hole, and dent, indentation from another side) 

 

This is a specimen like your one, when we have biting around ("represent failed attempts of the predator to successfully kill and consume its prey; instead, the prey organism has survived and repaired its shell.") 

 

 

"shows evidence of a crushing attempt by a predator, as suggested by distortion in the ribbing and intense, and likely rapid, repair in the area of the scar"

maybe it has been a small predator and a big brachiopod (too solid / hard for it / "to avoid small biting predators").  

 

And "Other such durophages as placoderm and chondrichthyan fishes and phyllocarid and (?)eumalacostracan arthropods, however, were also active predators (Signor and Brett, 1984; Leighton, 1999)." so there are so many questions ... and in Orbovic "Nautiloids also were efficient predators, equipped with crushing beaks and were major predators from the Ordovician through the Devonian (Alexander, 1986)." AND "The predation scars could have been produced by any one of these shell-crushing predators." 

 

@Mediospirifer @Shamalama @Al Tahan @Fossildude19

Edited January 16, 2020 by Brach3