Show me your six and seven gill shark teeth

[Woopaul5]

Hexanchus microdon 

Eocene 

Kyiu fm

Ukraine

[Woopaul5]

Notorynchus Sp

Mid Miocene

Batesford limestone

Victoria, Australia 

[fossilsonwheels]

On 2/6/2022 at 4:41 AM, Woopaul5 said:

Notorynchus Sp

Mid Miocene

Batesford limestone

Victoria, Australia 

Beautiful tooth, great location! 

[fossilsonwheels]

I normally save the taxonomic displays we’ve done for that specific thread but I thought it be cool to add these here. 

I’ve got two of our Cow Shark Displays done, Hexanchus and Notorynchus/Heptranchias. We have Notidanodon and Weltonia teeth in a third Riker but that is a work in progress. I think they are pretty nice visually and will definitely serve us well as educational tools. They are remarkable survivors. Being the oldest extant order does give them an importance educationally as does the adaptability they possess. They also have really cool looking teeth. 

 

[Woopaul5]

Updated pics of stuff I already posted to see if we can revive this thread.

 

Hexanchus griseus

Bahia Inglesa Fm

Copiapo, Chile

 

Notorynchus cepidianus

Calvert Fm

Calvert Co, MD

[Coco]

Wonderful !

 

Coco

[Woopaul5]

Hexanchus agassizi 

Eocene (Ypresian)

London clay

Isle of Sheppey, Kent, UK

 

 

[Dino9876]

Even if it is very late, here are a few recent hexanchid teeth:

 

Notorynchus cepedianus

 

Hexanchus griseus

 

Heptranchias perlo

 

Best regards from Germany  

[siteseer]

It's never too late for more hexanchids.

[Woopaul5]

Weltonia burnhamensis 

Eocene (Ypresian)

London Clay

Essex, England 

[Woopaul5]

Hexanchus collinsonae

Eocene (Ypresian)

Muddy Creek Site, VA

 

[Woopaul5]

Hexanchus griseus

Miocene

Nye mudstone

Portland, OR

[Woopaul5]

My attempt at putting together a Notidanodon loozi dentition together. From the Ouled Abdoun Phosphate beds in Oued Zem, Morocco. Paleocene (Thanetian) in age. 
 

It’s based off a modern Hexanchus griseus dentition.  With that being said, off that example it looks like I need the upper lower symphyseal’s and the first upper position. 
 

I’ve never gotten a definitive answer if a lower symphyseal actually exists for this species. I can’t remember ever seeing a complete one. I know there’s a heavily fabricated one on another composite that was sold in Tucson a few yrs ago but many people concluded that was two lowers put together. The ones that I’ve seen look like a cartoon crown hat kind of but I’ve never seen one not missing a cusp. 
 

Well really interested in your opinions on symphyseal for the specifies and also how I did. 
 

Thanks in advanced

 

Paul

Edited September 3, 2022 by Woopaul5
Addition to

[Coco]

@MarcoSr

 

Coco

[Woopaul5]

Here are the pic references I used 

[MarcoSr]

8 hours ago, Woopaul5 said:

My attempt at putting together a Notidanodon loozi dentition together. From the Ouled Abdoun Phosphate beds in Oued Zem, Morocco. Paleocene (Thanetian) in age. 
 

It’s based off a modern Hexanchus griseus dentition.  With that being said, off that example it looks like I need the upper lower symphyseal’s and the first upper position. 
 

I’ve never gotten a definitive answer if a lower symphyseal actually exists for this species. I can’t remember ever seeing a complete one. I know there’s a heavily fabricated one on another composite that was sold in Tucson a few yrs ago but many people concluded that was two lowers put together. The ones that I’ve seen look like a cartoon crown hat kind of but I’ve never seen one not missing a cusp. 
 

Well really interested in your opinions on symphyseal for the specifies and also how I did. 
 

Thanks in advanced

 

Paul

 

5 hours ago, Coco said:

@MarcoSr

 

Coco

 

I think this is the symphyseal tooth that you were talking about.  Definitely looks like a composite to me.

 

 

 

 

See the below Figure (R, S)  from Cappetta 2012 which shows a Notidanodon loozi lower symphyseal tooth.  The other teeth in the figure should help with positioning other teeth in your dentition.

 

 

 

 

Since all the extant six and seven gill sharks (not considering Chlamydoselachus), have upper symphyseal teeth and the fossil ones that I'm familiar with have upper symphyseal teeth, I would expect N. loozi to have upper symphyseal teeth. 

 

Again, based upon extant six and seven gill sharks (not considering Chlamydoselachus), I would also expect N. loozi to have commissural teeth.  Commissural teeth are very small, which probably explains why they are extremely rare in the fossil record.

 

Marco Sr.

[Woopaul5]

36 minutes ago, MarcoSr said:

 

 

I think this is the symphyseal tooth that you were talking about.  Definitely looks like a composite to me.

 

 

 

 

 

 

See the below Figure (R, S)  from Cappetta 2012 which shows a Notidanodon loozi lower symphyseal tooth.  The other teeth in the figure should help with positioning other teeth in your dentition.

 

 

 

 

Since all the extant six and seven gill sharks (not considering Chlamydoselachus), have upper symphyseal teeth and the fossil ones that I'm familiar with have upper symphyseal teeth, I would expect N. loozi to have upper symphyseal teeth. 

 

Again, based upon extant six and seven gill sharks (not considering Chlamydoselachus), I would also expect N. loozi to have commissural teeth.  Commissural teeth are very small, which probably explains why they are extremely rare in the fossil record.

 

Marco Sr.

 

That’d be the one!!! 
 

Thanks for your help!!!

 

Edited September 3, 2022 by Woopaul5

[fossilsonwheels]

Haven’t had the occasion to post any Hexanchiformes in awhile. We were very lucky to have gotten some fairly recently from @Woopaul5. He sent us a nice assortment and this was my favorite. Only our second 7 Gill symphyseal tooth and from Lee Creek no less! 

 

Notorhynchus cepedianus

Miocene

Pungo River Formation 

Lee Creek NC

[siteseer]

Here is a rare Hexanchus (sixgill shark) tooth from the Early Paleocene of New Jersey.  It was collected by a researcher who has since passed away - good guy.  We traded a couple of times in the early-mid 90's and this is one of the specimens I received from him.

 

This may be an early H. agassizi or late-surviving H. microdon.   

 

Hexanchus sp.

Early Paleocene

Lower Hornerstown Formation

site in Monmouth County, New Jersey

just over 8mm long

 

 

Edited December 22, 2022 by siteseer

[fossilsonwheels]

A recent addition and one that I’m super stoked about. Never thought we’d add one of these. 

 

Hexanchus gigas

Miocene/Pliocene 

Bahia Ingles

Copiapo, Chile

[siteseer]

Nice!

[fossilsonwheels]

On 12/25/2022 at 10:53 PM, siteseer said:

Nice!

Thanks Jess !

[fossilsonwheels]

Hexanchus andersonii

Miocene

Round Mountain Silt

Kern Co California 

 

A nice in situ lower tooth from STH. 

[fossilsonwheels]

Hexanchus griseus

Pliocene

Capistrano Formation 

Orange Co California 

[rocket]

oh, wow, great teeths...

we can contribute with a special one, actually not determined shark from Solnhofen, length approx. 25 cm, fantastic and great preserved denture