Fossil “armpit”?

[Jemstar]

Hi All, this is my first post. I recently found this interesting bit in southern Ontario.  It was in the same river that I find brachiopods and trilobites. 

I couldn’t figure out what it was, but I think I may have now solved it, maybe you can confirm? 
 

I’m affectionately referring to it as an “armpit” of a Bothriolepis. Obviously not an armpit but I think it might be the part where the appendage meets the head shield? My concern is the size of my specimen. The one in the book is only 90mm for the full body. That’s basically the size of my partial specimen.

I’m open to all interpretations, friends. Thanks.

Edited September 24, 2022 by Jemstar
Added photo from book

[connorp]

Nice find! Definitely fish bone. The tubercules suggest placoderm armor. Do you know what formation this came from? That will probably be necessary to give any more definitive of an ID.

[Misha]

Very interesting find!

Certainly looks fishy, but I do not think this is the joint of the flipper, as the parts here look fused. It also doesn't really look like Bothriolepis, especially considering the brachiopods you already posted (I assume those are the ones you are referring to) which are mid Devonian while Bothriolepis is found in the Late Devonian. 

Could this maybe be something like Protitanichthys? I've heard of them being found around there in the Mid Devonian

Edited September 24, 2022 by Misha

[Jemstar]

50 minutes ago, connorp said:

Nice find! Definitely fish bone. The tubercules suggest placoderm armor. Do you know what formation this came from? That will probably be necessary to give any more definitive of an ID.

Thank you, this was in the Arkona formation.

 

48 minutes ago, Misha said:

Very interesting find!

Certainly looks fishy, but I do not think this is the joint of the flipper, as the parts here look fused. It also doesn't really look like Bothriolepis, especially considering the brachiopods you already posted (I assume those are the ones you are referring to) which are mid Devonian while Bothriolepis is found in the Late Devonian. 

Could this maybe be something like Protitanichthys? I've heard of them being found around there in the Mid Devonian

Yes that makes sense, thank you. They are all from the same spot, collected in a river and along the banks.  I will look up Protitanichthys, thanks for the info!

[Ludwigia]

Maybe @Kane has an idea since he has found some Middle Devonian Placoderm parts in the past.

[Fossildude19]

@jdp

[mr.cheese]

Really nice find though I am slightly disappointed that it wasn't the promised fossilised armpit!

[Kane]

It could also be Protitanichthys sp. The piece seems to be from the Widder Fm (judging by the shale).

[Jemstar]

8 hours ago, mr.cheese said:

Really nice find though I am slightly disappointed that it wasn't the promised fossilised armpit!

Lol I’m so sorry! 

[Jemstar]

10 hours ago, Kane said:

It could also be Protitanichthys sp. The piece seems to be from the Widder Fm (judging by the shale).

Thanks for that! I just learned two new things, much appreciated.

[jdp]

Definitely placoderm. I think this is part of the thoracic shield, with the pectoral fin sitting within that embayment. That doesn't quite fit morphologically with Protitanichthys, but that may be a consequence of preservation. 

[Jemstar]

Thanks for that info!