cretalamna appendiculata ?

[Hipockets]

I am still trying to learn to identify all the many sharks teeth , after some research ( books, elasmo.com, and other sites,including this one) I think this may be cretalamna ? It is from the the Neuse River in NC, eocene and cretaceous. The first 4 pics are first tooth the last 4 pics are a second tooth. Neither have much (if any) nutrient groove, more of a foramen. I was thinking they are both same ,just different position? Scale is in mm.   Thanks 

[sixgill pete]

I think you are correct on this one.

[Macrophyseter]

I also agree, especially for the second one (I first thought that the first pic was from a scapanorhynchus until I read your text, silly me , now why do I always assume that little goblin shark as the one?) (I completely forgot about Striatolamia, and I'm leaning towards that for the first one.)

 

I usually dictate Cretolamna with very large cusps and a wide or narrowish crown depending on the species. When it comes down to species, I believe that C. appendiculata is one of the only species without double cusps (two cusps on each side), but I may be wrong.

[Anomotodon]

I don't think the first one is Cretalamna, either Striatolamia macrota (if Eocene is an option) or Scapanorhynchus cf. texanus upper lateral. Laterals of Striatolamia are similar to Scapanorhynchus, but are slightly more flattened and can have smaller nutrient grooves (you can see it on this root, but it is also heavily worn and therefore it is not a significant characteristic).

 

By the way, it is incorrect to identify Maastricthian-Campanian Cretalamnas as C. appendiculata. M. Siverson did a revision of this genus in 2013, and C. appendiculata is now known only from Turonian. Stratigraphically speaking, the second tooth here (as well as other Cretalamnas from East Coast Late Cretaceous) is either C. sarcoportheta or C. borealis. Most likely C. borealis, as it is described from Delaware.

Cenomanian—Campanian (Late Cretaceous) Mid-Palaeolatitude Sharks of Cretalamna appendiculata Type 

[Macrophyseter]

16 minutes ago, Anomotodon said:

I don't think the first one is Cretalamna, either Striatolamia macrota (if Eocene is an option) or Scapanorhynchus cf. texanus upper lateral. Laterals of Striatolamia are similar to Scapanorhynchus

Oh my, why did I forget about Striatolamia? And yes, Eocene is an option, so I'm leaning towards Striatolamia for the first one as well. And seeing that Hipokets added cretaceous as a possible temporal range (or I'm just a really, really bad reader), Scapanorhynchus is also a great option as well.

[non-remanié]

Striatolamia and Cretolamna is what i see.  Although, i technically don't see the striations to make it Striatolamia on the first.  But you can tell better with it in your hand if it does have striations.  

[MeargleSchmeargl]

Looks like it. Nice work!

[Hipockets]

Thanks everyone for the feedback. Just to clarify, there is no striations on either tooth. Happy new Year !

[Plax]

On 12/31/2017 at 4:34 PM, Anomotodon said:

I don't think the first one is Cretalamna, either Striatolamia macrota (if Eocene is an option) or Scapanorhynchus cf. texanus upper lateral. Laterals of Striatolamia are similar to Scapanorhynchus, but are slightly more flattened and can have smaller nutrient grooves (you can see it on this root, but it is also heavily worn and therefore it is not a significant characteristic).

 

By the way, it is incorrect to identify Maastricthian-Campanian Cretalamnas as C. appendiculata. M. Siverson did a revision of this genus in 2013, and C. appendiculata is now known only from Turonian. Stratigraphically speaking, the second tooth here (as well as other Cretalamnas from East Coast Late Cretaceous) is either C. sarcoportheta or C. borealis. Most likely C. borealis, as it is described from Delaware.

Cenomanian—Campanian (Late Cretaceous) Mid-Palaeolatitude Sharks of Cretalamna appendiculata Type 

Very good information! The lumpers would probably still like the old taxon and consider the chronospecies subspecies. (not me)