Pennsylvanian Period Tooth?

[LanceH]

I know I've seen this thing somewhere but can't find where I saw it.

Anyway found this on Saturday in the late Pennsylvanian age 'Palo Pinto' formation in Texas.

[Guest solius symbiosus]

I have no experience with verts, but that looks like a hypostome off of a trilobite.

[LanceH]

Naw, I think it's a fish or shark tooth...

I have no experience with verts, but that looks like a hypostome off of a trilobite.

[geofossil]

That's an interesting specimen.

It certainly 'looks' Chondrichthyan. I went through my Carboniferous shark teeth but don't have anything quite like it. One feature that 'sort of' points it in a direction is the symmetry of the two sides. I'd take a wild guess at being a tooth plate from a 'petalodont' shark...but...not 'Petalodus' or a known species. There's a wide range of symmetrical teeth from the petalodont grouping and many don't resemble the typical 'Petalodont' but have multiple rounded points ranging from about 10 in 'Ctenopychius' to the one flat one in 'Petalodus'. .

A lot of paleozoic shark material is unique and unstudied.It's probably questionable 'who is related to who' as a lot of early shark lines are based on a few specimen and groupings are educated speculation. I would free some from matrix with acid and take them to an old emeritus paleontologist who wrote a couple of papers on them. He would put 'probably new genus' on some of them. It wasn't even certain if some were teeth, modified scales and so on.

Do you have other shark teeth from this age? It'd be great to see some photos. We all want to collect that big Megalodont or T-rex tooth but from a pure scientific perspective, those little paleozoic tooth specimens are top on my list.

[Harry Pristis]

I have no experience with verts, but that looks like a hypostome off of a trilobite.

If there's anyone here not familiar with a trilobite hypostome, here's what Solius is suggesting.

[hybodus]

Hi Lance,

The labial side (still has some enamel), makes me think broken Peripristis with a funky root. The lingual side makes me think Janassa sp. I am tempted to lean towards Janassa. I think you could safely label it Paleozoic shark...

[geofossil]

Hi Lance,

The labial side (still has some enamel), makes me think broken Peripristis with a funky root. The lingual side makes me think Janassa sp. I am tempted to lean towards Janassa. I think you could safely label it Paleozoic shark...

Both of those are petalodonts. I'd be tempted to call it a shark tooth and probably a petalodont....possibly a new genus. There are few Carboniferous non-micro shark teeth other than petalodonts and cladodonts that are symmetrical and also have a greater or equal height than width. (At least known ones. There's just not many complete fossil specimens with extensive whorls to get too specific on these critters)

[hybodus]

Geofossil, I agree it's probably a petalodont. I would be VERY hesitant to say a new genus. Way to many genera have been erected for Paleozoic Sharks... tooth design is not always the best indicator, especially a single isolated and incomplete tooth from a particular locality - should never be considered a new genus from the get go.

Many Paleozoic sharks exhibit a tremendous amount of variation in tooth design. What leads you to believe it may be a possible new genus? Not trying to be confrontational in any way here, but I also have a particular soft spot for Paleozoic sharks, and a pretty good collection (sounds like you do as well!).

Best Regards,

Norm

[Archimedes]

I know I've seen this thing somewhere but can't find where I saw it.

Anyway found this on Saturday in the late Pennsylvanian age 'Palo Pinto' formation in Texas.

Hi Lance,

Very Nice tooth

I agree with the comments on this tooth

My frist impression was a Janasssa related tooth but never seen one quit like yours

[Archimedes]

Hi Lance

while reviewing some vert. fossil journals I seen several identical pics in an aricule on paleozoic shark teeth

and the Genus they assigned to it was Fissodus

the articule went on to say Fissodus was related to Janasssa

[Permian-Friend]

This is exactly a symphyseal tooth of a petalodont shark Janassa korni. We know such petalodontids from the Upper Permian of Germany a single complete specimen, a lot of sets of teeth, placoid scales and the body outline form. Most of sharks have different types ot teeth, so it is difficult to determine finds of single teeth. A lot of described "historical species" could belong to only a few species.

Sorry for my English it is not so good.

With regards from Germany

Permian-Friend

[LanceH]

Thank you so much.