Tilly bone or coprolite?

[Thomas1982]

Hi all,

 

I found this on Matoaka Beach, Calvert Cliffs, Mayrand.  Sorry I don't have a ruler with the image - as you can see it is quite small - about 15mm

 

Thanks,

Tom

[debivort]

Also looks a bit like a tympanic bulla.

[Carl]

Too closed for a bulla in my eyes. Not seeing a coprolite. Looks boney.

[Shellseeker]

8 hours ago, Thomas1982 said:

Hi all,

 

I found this on Matoaka Beach, Calvert Cliffs, Mayrand.  Sorry I don't have a ruler with the image - as you can see it is quite small - about 15mm

 

Thanks,

Tom

Hi Tom,

@Plantguy has a collection of Tillys,  I would be interested in his comments...

The redline below seems to go through the find both front and back, on almost exact opposite positions. Is that your perception also?

 

I am reaching in terms of possibilities... I tend of think Tilly 1st and then a Bulla earbone of a small marine mammal... Note the wavy crevice on the lower left and the vertical grooves on lower right..  Similarities ,  but not the same... Possibly pathological...  Worth a comment from @Boesse and @Al Dente. Just attempting to generate an interesting conversation...

[Harry Pristis]

My impression is that most Tilly bones have at least a hint of bilateral symmetry.  By elimination (NPI) this must be a coprolite.  I don't know what sort of cloacal valve folds the pellet in the manner presented, but I think that coprolite is a reasonable conclusion.

[Boesse]

If it looks like it's spiraled in cross-section, it could be a type of scroll coprolite produced by a skate/ray. Not a bulla.

[Plantguy]

I dont think Tilly--it has some similarity to some but more dissimilarity--and agree with Harry, the general lack of symmetry makes me lean towards a possible coprolite. I am intrigued by the spiral like/fine linear features I marked in red below--should have chosen a different color...sorry Jack! @Shellseeker Wonder if Lori can tell us if those are coprolitic features. @GeschWhat Dont I remember someone on the eastcoast having an excellent small coprolite collection donation from up that away.??

I wonder if the redlined longitudinal feature you made Jack is simply some dessication cracking?

Curious to see if there might be a petrosal/bulla possibility and Bobby's thoughts.

I see Carl's point about it possibly being boney and am wondering if we can rule that out by looking more closely here? looks like a fresh crack/chip?

 

 

I also did think also about possible seeds as well. Vitus has a couple of possibilities, one in particular but the unknown appears to be

much larger ( I/J below : 

Published in 2010

Vitis seeds (Vitaceae) from the late Neogene Gray Fossil Site, northeastern Tennessee, U.S.A.

Fade Gong, I. Karsai, Y. Liu

 

Figure 4 Representative Seeds for Genera of Vitaceae. Scale bar =1mm. A-B. Dorsal and ventral views of Ampelocissus acapulcensis; C-D. Dorsal and ventral views of Ampelopsis brevipedunculata; E-F. Dorsal and ventral views of Cayratia japonica; G-H. Dorsal and ventral views of Cissus incisa; I-J. Dorsal and ventral views of Nothocissus spicifera, (adapted from Chen and Manchester 2007); K-L. Dorsal and ventral views of Parthenocissus quinquefolius

 

[Shellseeker]

Wow  !!! This has become an interesting thread,  with lots of new things for me to think about... "Scroll coprolite"   and Nothocissus spicifera.... seeds  huh,  Chris....

 

[GeschWhat]

I’m thinking coprolite, possibly a spiral, but looking at it on my phone. I’ll take a closer look later when I can look at it on my computer.  

 

@Carl is more familiar with Calvert Cliffs. 

[Thomas1982]

Thanks everyone!  I am adding some more pictures with better lighting:

 

[Carl]

I'm leaning towards tilly bone of some sort.

[Shellseeker]

@Plantguy Here is one of yours that just seems to have the right texture..

 

Possibly due to the river flow,  all the coprolites I find tend to be smooth. I hope @GeschWhat can provide some with tiny details....

[Carl]

2 hours ago, GeschWhat said:

I’m thinking coprolite, possibly a spiral, but looking at it on my phone. I’ll take a closer look later when I can look at it on my computer.  

 

@Carl is more familiar with Calvert Cliffs. 

Just a tiny bit, actually.

[automech]

[Shellseeker]

I was searching thru photo folders,  and found these photos... 5 years ago while searching for Megs 12-15 feet below Pleistocene Bone layers...  They turned out to be identifiable...

 

 

It may not be one of these specific Tilly forms, but the the texture that we are seeing on OPs find,  has me leaning toward Tilly,  UNTIL I see a coprolite with similar textures.

[Harry Pristis]

Do you not see the bilateral symmetry in your examples, Jack?

Do you see similar symmetry in the mystery find?

The original poster most likely has found a coprolite from a chondrichthyan, a small shark or ray, which had a spiral cloacal valve.

[Plantguy]

Jack I'm chuckling here as I'm going thru tilly photos...but that spiraling nature that Bobby pointed out right before my post last night and Harry just noted still makes me lean away from Tilly--to me its just slightly different than the ones that I have and certainly I dont have all kinds but I can see the argument/case for the Tilly.

 

I'm gonna paste in this compiled photo of 15 tillys and take the wrath of everyone for taking group photos in a haphazard attempt to show variety from 3 different views of each of them, but I was admittedly playing around and being sloppy and things were falling over but you can zoom and see some that possibly look like the unknown, possibly its a part of one?.

Im still not convinced though...

Future posters dont do this--I was experimenting!! 

 

Regards, Chris 

[Shellseeker]

17 hours ago, Harry Pristis said:

Do you not see the bilateral symmetry in your examples, Jack?.... Absolutely....

Do you see similar symmetry in the mystery find? .... A little, but not very much

 

The original poster most likely has found a coprolite from a chondrichthyan, a small shark or ray, which had a spiral cloacal valve.

So,  lack of equivalent symmetry versus the texture /fine lines of OPs fossil.... gets me to the position that it is very reasonable to view this as a coprolite from a chondrichthyan.. I was waiting for one of the supporters of that view to produce a photo of such a coprolite that is similar to Ops find.

My experience with coprolites is that they are mostly smooth,  little texture or fine lines...

19 hours ago, Shellseeker said:

...... but the texture that we are seeing on OPs find,  has me leaning toward Tilly,  UNTIL I see a coprolite with similar textures.

I have been searching the Internet unsuccessfully.... This about the closest I could find...  Seems to be approximately the correct size... As the text under the photo indicates, it does have a longitudinal striation...

Quote

A well-preserved vertebrate coprolite is reported from the Middle Danian Faxe Formation of Faxe quarry, Denmark. The coprolite differs from earlier reported coprolites from Faxe in being heteropolar and microspiral in morphology, with a short posterior spire and a blunt anterior termination.

[Al Dente]

I’m convinced it is a Tilly bone. Not all Tilly bones have bilateral symmetry. Here are a few common types from the Pliocene Yorktown Formation of NC.

 

 

[Harry Pristis]

No, I wouldn't argue that ALL Tilly bones have bilateral symmetry.  On the other hand, how can we determine that there is NO symmetry in the objects you present from one side.  Which fish bone do you propose is producing such overgrowth?

On 6/21/2023 at 7:45 PM, Harry Pristis said:

My impression is that most Tilly bones have at least a hint of bilateral symmetry.  

 

[Plantguy]

18 hours ago, Al Dente said:

I’m convinced it is a Tilly bone. Not all Tilly bones have bilateral symmetry. Here are a few common types from the Pliocene Yorktown Formation of NC.

 

 

@Al DenteThose are quite nice! I do have some odd ones as well but I'm still leaning away from that ID. I'm trying to remember someone on the forum here that had an extensive small coprolite collection from an east coast site a couple years ago? that they donated/were having looked at. I saw it in a thread somewhere. Was that you? MarcoSr? I'm wondering if there is anything in that collection that could help to settle this?

 

I surely want to section that thing to see what its internal structure looks like if that can be determined by looking at the fragmented edges.. 

 

Regards, Chris 

[Al Dente]

4 hours ago, Plantguy said:

I saw it in a thread somewhere. Was that you? MarcoSr?

Yes, it was @MarcoSr.

[MarcoSr]

14 hours ago, Al Dente said:

Yes, it was @MarcoSr.

 

I've looked at the pictures of this specimen multiple times and I just don't have a definitive opinion.  To me both a coprolite or tilly bone are possible from the pictures.  It is a type of specimen that I need to see in person and move in my fingers to get just the right angles of view and then look at under a 10x loupe.

 

Marco Sr.

[Thomas1982]

On 6/25/2023 at 6:00 AM, MarcoSr said:

 

I've looked at the pictures of this specimen multiple times and I just don't have a definitive opinion.  To me both a coprolite or tilly bone are possible from the pictures.  It is a type of specimen that I need to see in person and move in my fingers to get just the right angles of view and then look at under a 10x loupe.

 

Marco Sr.

 

Hi Marco,

 

Would you be willing to examine the specimen if I mail it to you?  I would really appreciate it - I hate labelling fossils as 'unknown' in my collection ;-)

 

Thanks,

Tom

 

[MarcoSr]

On 6/26/2023 at 9:11 AM, Thomas1982 said:

 

Hi Marco,

 

Would you be willing to examine the specimen if I mail it to you?  I would really appreciate it - I hate labelling fossils as 'unknown' in my collection ;-)

 

Thanks,

Tom

 

 

Tom I received the specimen today.  I took a couple of quick pictures in which I tried to focus on the specimen texture which I think settles the debate.

 

 

 

 

 

 

 

Marco Sr.