Show us your rarest sharks tooth

[siteseer]

Here's a very rare bramble shark tooth from the Calvert Formation.  I've seen it identified as E. blakei though that species may be exclusive to the Middle Miocene of California.  I'll leave it as Echinorhinus sp.

[Styles]

5 hours ago, siteseer said:

 

I'm not sure about that.  Welton and Farish (1993) noted that P. latissimus is common in Texas.  I saw a number of specimens at the 1994 or 1995 MAPS EXPO found by the late Ken Smith.

 

Welton, B. and R. Farish.  1993.

The Collector's Guide to Fossil Sharks and Rays from the Cretaceous of Texas. Before Time, Texas. 204 pp.

Yeah, it seems murky. Anecdotally, I’ve seen 3 or 4 from North Texas. And I have the book by Roger Farish which lists them as “common” as you mention.  So I think in reality it’s probably between “kinda common” and “rare” but not “super rare”. The paper I mentioned in my original post is called “The first occurance of ptychodus latissimus from the coddell sandstone”. In it, Shawn writes:

 

”In the Western Interior Seaway Ptychodus latissimus is known only by isolated teeth and has its first and only occurrence during the middle Late Turonian to the Early Coniacian. To date, only 31 teeth have been reported, primarily from the basal Atco Formation of the Austin Chalk in Texas (Welton and Farish
1993; Hamm 2004, 2005, 2008; Hamm and Cicimurri 2011) and a single tooth from the Sage Breaks Member of the Carlile Shale in South Dakota (Cicimurri 2004).

…..

The disparity in the number of Ptychodus latissimus specimens from the Western Interior Seaway is intriguing. The majority of specimens recovered from North America are from a residual lag deposit that sits on top of a disconformity at the Austin-Eagle Ford Group contact zone in north central Texas (Hamm 2008, 2009, 2020; Hamm and Cicimurri 2011). “

 

I’d consider Shawn to be the foremost expert on ptychodus in the WIS, as I would Farish for shark teeth in the WIS, so the disparity is odd. On Mike Everhart’s website and books, it seems as though he didn’t have much to document and even shows specimens from outside the US to describe. So I guess there isn’t really consensus. Out of the probably 1000 ptychodus I’ve found from a couple dozen sites across N Tx, I’ve only found one (possibly two - unsure of the other due to it being on the fringes of the dentition which makes it much harder for me to differentiate between species.)  Not mine anyway anymore - donated it to Shuler after chatting with Shawn and Dr. Winkler.  I’d like to add though that my fossil knowledge is still nascent, especially when compared with some of the people on this forum like yourself, so I defer to the opinion and experience of the experts here. Really appreciate your insight - find all of this fascinating.  
 

On a separate note, I’ll take the opportunity to show off my other rare tooth - an almost 2 3/4” Cretoxyrhina found in the eagle ford / AC contact of north texas. Cretoxyrhina is common, but specimens of this size and condition are rare.  Going back to Farish’s book, it’s larger than the upper bounds of the range for mantelli. 

Edited August 16, 2022 by Styles

[siteseer]

On 8/16/2022 at 5:39 AM, Styles said:

Yeah, it seems murky. Anecdotally, I’ve seen 3 or 4 from North Texas. And I have the book by Roger Farish which lists them as “common” as you mention.  So I think in reality it’s probably between “kinda common” and “rare” but not “super rare”. The paper I mentioned in my original post is called “The first occurance of ptychodus latissimus from the coddell sandstone”. In it, Shawn writes:

 

”In the Western Interior Seaway Ptychodus latissimus is known only by isolated teeth and has its first and only occurrence during the middle Late Turonian to the Early Coniacian. To date, only 31 teeth have been reported, primarily from the basal Atco Formation of the Austin Chalk in Texas (Welton and Farish
1993; Hamm 2004, 2005, 2008; Hamm and Cicimurri 2011) and a single tooth from the Sage Breaks Member of the Carlile Shale in South Dakota (Cicimurri 2004).

…..

The disparity in the number of Ptychodus latissimus specimens from the Western Interior Seaway is intriguing. The majority of specimens recovered from North America are from a residual lag deposit that sits on top of a disconformity at the Austin-Eagle Ford Group contact zone in north central Texas (Hamm 2008, 2009, 2020; Hamm and Cicimurri 2011). “

 

I’d consider Shawn to be the foremost expert on ptychodus in the WIS, as I would Farish for shark teeth in the WIS, so the disparity is odd. On Mike Everhart’s website and books, it seems as though he didn’t have much to document and even shows specimens from outside the US to describe. So I guess there isn’t really consensus. Out of the probably 1000 ptychodus I’ve found from a couple dozen sites across N Tx, I’ve only found one (possibly two - unsure of the other due to it being on the fringes of the dentition which makes it much harder for me to differentiate between species.)  Not mine anyway anymore - donated it to Shuler after chatting with Shawn and Dr. Winkler.  I’d like to add though that my fossil knowledge is still nascent, especially when compared with some of the people on this forum like yourself, so I defer to the opinion and experience of the experts here. Really appreciate your insight - find all of this fascinating.  
 

On a separate note, I’ll take the opportunity to show off my other rare tooth - an almost 2 3/4” Cretoxyrhina found in the eagle ford / AC contact of north texas. Cretoxyrhina is common, but specimens of this size and condition are rare.  Going back to Farish’s book, it’s larger than the upper bounds of the range for mantelli. 

 

I'm far from an expert on Texas sharks.  Of course, when Shawn Hamm notes "reported teeth" that means specimens in museum collections.  I would assume some museums have more of them.  They just haven't been identified.  I haven't seen a lot of these teeth.  In fact most of the ones I've seen were at that MAPS show.

 

Wow, that is a gigantic Cretoxyrhina.  I think that's the largest one I've seen.  It's tough enough to find one just clearing two inches.

 

[Jared C]

On 8/16/2022 at 7:39 AM, Styles said:

. 

oh... my gosh 

 

@ThePhysicist are you seeing this thing!?

[ThePhysicist]

17 hours ago, Jared C said:

oh... my gosh 

 

@ThePhysicist are you seeing this thing!?

 WOW WOW!

That's a huge anterior, this is definitely one of the largest I've seen and probably approaches the maximum for the species - especially uncommon in NTX where the ginsu appears to usually be smaller than say the Coniacian of KS. Really great find, @Styles! 

[Styles]

1 hour ago, ThePhysicist said:

 WOW WOW!

That's a huge anterior, this is definitely one of the largest I've seen and probably approaches the maximum for the species - especially uncommon in NTX where the ginsu appears to usually be smaller than say the Coniacian of KS. Really great find, @Styles! 

 

Thank you! Almost thought it was a wayward angustidens replica when i was walking up to it.  My brain wouldn't let me believe it.

[Notidanodon]

On 8/16/2022 at 9:08 AM, siteseer said:

Here's a very rare bramble shark tooth from the Calvert Formation.  I've seen it identified as E. blakei though that species may be exclusive to the Middle Miocene of California.  I'll leave it as Echinorhinus sp.

Great tooth Jess where did you get that one from!

[siteseer]

On 8/19/2022 at 5:43 PM, will stevenson said:

Great tooth Jess where did you get that one from!

 

I got it in a trade years ago.  A Maryland dealer/collector was able to make a deal with someone else for 2-3 specimens.  He said he could trade me "the ugly one" and I said I'd take it knowing how rare they are. 

[fossilsonwheels]

Haven’t posted to this thread in awhile. I very recently added a pretty elusive tooth to the collection. While not a Chlamydoselachus tooth, it is a Frilled Shark and it will be the only one I ever own. Super excited to add another awesome deep water shark ! 

 

Rolfodon ludvigseni

Cretaceous

Northumberland Formation 

Collishaw Point 

Hornby Island, BC

[rocket]

I have a few, together in an currently indetermined shark from Solnhofen

could be a new genus 

[fossilsonwheels]

The Northumberland Formation has provided us with a number of rarities. A few Cow Sharks, a few Squaliformes, a Frilled Shark and our first Pristiophorus oral tooth !!!! 

 

Pristiophorus smithi

Cretaceous 

Northumberland Formation 

Collishaw Point

Hornby Island BC

[Doctor Mud]

On 3/3/2023 at 12:04 AM, rocket said:

I have a few, together in an currently indetermined shark from Solnhofen

could be a new genus 

What a beautiful fossil!! Such great preservation! 

[Dino9876]

On 3/4/2023 at 6:37 AM, fossilsonwheels said:

The Northumberland Formation has provided us with a number of rarities. A few Cow Sharks, a few Squaliformes, a Frilled Shark and our first Pristiophorus oral tooth !!!! 

 

Pristiophorus smithi

Cretaceous 

Northumberland Formation 

Collishaw Point

Hornby Island BC

 

I unfortunately don't have anything to add, but I love your posts. It's great to see such rare teeth here in the forum. Keep it up!

 

Best regards from Germany

[Tales From the Shale]

I don't know if this is technically a shark or not but,

Peripristis semicircularis

Bond Formation: Pennsylvanian

Illinois

Edited March 6, 2023 by Tales From the Shale

[siteseer]

Here's a Parotodus from Florida that might be the species, P. oligocaenus, which I have read is valid.  I bought this around the mid-90's as part of a small lot from the Suwannee River, Florida.  I wasn't sure what it was at the time and Parotodus wasn't an in-demand genus like it is now.  The dealer said this and the other teeth washed out of the Ocala Limestone (Late Eocene). 

 

I actually lost track of this tooth for a few years and was even afraid I might've traded it somewhere down the line but found it recently with another tooth from the same site in a zip-lock - somehow ended up in the wrong box.  It measures just over 1 1/8 inches. 

 

 

[siteseer]

On 3/5/2023 at 5:26 PM, Tales From the Shale said:

I don't know if this is technically a shark or not but,

Peripristis semicircularis

Bond Formation: Pennsylvanian

Illinois

 

Well, it's a cartilaginous fish from the Paleozoic.  It's not of a lineage that led to modern sharks but it's at least a distant cousin so it's close enough in the big scheme of things.

 

[Notidanodon]

14 hours ago, siteseer said:

Here's a Parotodus from Florida that might be the species, P. oligocaenus, which I have read is valid.  I bought this around the mid-90's as part of a small lot from the Suwannee River, Florida.  I wasn't sure what it was at the time and Parotodus wasn't an in-demand genus like it is now.  The dealer said this and the other teeth washed out of the Ocala Limestone (Late Eocene). 

 

I actually lost track of this tooth for a few years and was even afraid I might've traded it somewhere down the line but found it recently with another tooth from the same site in a zip-lock - somehow ended up in the wrong box.  It measures just over 1 1/8 inches. 

 

 

Cool one, unusual!

[fossilsonwheels]

Trigonotodus alteri

Oligocene

Ashley Marl

Summerville South Carolina 

 

A rare cusped Giant Thresher tooth. 

[siteseer]

On 6/8/2023 at 11:39 PM, fossilsonwheels said:

Trigonotodus alteri

Oligocene

Ashley Marl

Summerville South Carolina 

 

A rare cusped Giant Thresher tooth. 

 

Nice one, Kurt.  I saw a couple of those in the late 90's-early 2000's and was able to pick up one for myself.  You hardly ever see one these days.

 

[fossilsonwheels]

On 6/24/2023 at 1:04 AM, siteseer said:

 

Nice one, Kurt.  I saw a couple of those in the late 90's-early 2000's and was able to pick up one for myself.  You hardly ever see one these days.

 

I got lucky. I saw it on the auction site and grabbed it. I wasn’t expecting to find one in all honesty. 

[fossilsonwheels]

Heptranchias karagalensis

Eocene

Shorym Formation 

Sary-Niaz Mangyshlak

Kazakhstan 

 

Another rare Heptranchias. This one an Eocene from Kz. 

[reefer_man_kz]

On 16.08.2022 at 13:08, siteseer said:

Вот очень редкий зуб ежевичной акулы из формации Калверт. Я видел, что его идентифицировали как E. blakei, хотя этот вид может быть эксклюзивным для среднего миоцена Калифорнии. Я оставлю это как Echinorhinus sp.

Hello. I have a little more than a dozen similar teeth found in a couple of years. In our region, they are classified as Echinorhinus caspius Glikman. It's pretty hard to see them.. I didn't think they were rare..

[Notidanodon]

1 hour ago, reefer_man_kz said:

Hello. I have a little more than a dozen similar teeth found in a couple of years. In our region, they are classified as Echinorhinus caspius Glikman. It's pretty hard to see them.. I didn't think they were rare..

very nice finds  they are definitely rare in the calvert formation but thats because it represents a marine environment and geological age where Echinorhinus was less common, also i believe the species you have is Echinorhinus zheleskovi

[reefer_man_kz]

18 hours ago, Notidanodon said:

очень хорошие находки,  они определенно редки в формации Кальверт, но это потому, что они представляют собой морскую среду и геологический возраст, где Echinorhinus был менее распространен, также я считаю, что у вас есть вид Echinorhinus zheleskovi.

Thanks for your comment.. Perhaps you are right and we have another kind. But I only found these ones.))