Benedini or Mako?

[VAfossilguy]

Hello all! I am hoping someone can give me a definitive answer about this tooth I found. Is this a Benedini or a Mako? Fyi,  its  less than a tenth of an inch from being 3 inches.

[The Jersey Devil]

It is neither mako or benedini. It’s the giant white shark, Carcharodon hastalis. Real nice tooth.

[Troodon]

Agree lower White Shark

[VAfossilguy]

Any particular characteristics seen to confirm it not being a Benedini, but an Hastalis instead? Not disagreeing at all, especially after looking at examples of Hastalis fossils. Just wanting to know for my own reference. 

[FossilsAnonymous]

@VAfossilguy 

Here’s mine. It matches very well with yours.

This has been positively identified as c.hastalis.

[siteseer]

On 2/13/2020 at 7:09 PM, VAfossilguy said:

Any particular characteristics seen to confirm it not being a Benedini, but an Hastalis instead? Not disagreeing at all, especially after looking at examples of Hastalis fossils. Just wanting to know for my own reference. 

 

 

First of all, I also agree that it's a Carcharodon hastalis lower tooth and maybe the first anterior.  Sometimes, it helps to identify the jaw position first when you are considering an ID for genera with similar teeth.  It's not a Parotodus because it lacks a bourlette (= chevron-shaped neck) typical for the genus.  Sometimes, this feature is worn away but there is still some indication that it was present.  It also lacks the lingual protuberance (distinct bulge on the central part of the root on the lingual side) typical for the genus.  In Parotodus the crown is generally shorter relative to the height of the root.  On this tooth the crown is clearly taller than the root.  All in all the features and proportions point to an ID away from Parotodus and in favor of C. hastalis.

 

I understand why you might have considered Parotodus because it looks like a rather thick tooth.  The tooth might have been infiltrated by water during fossilization and suffered some temperature extremes.  It might have expanded, contracted, and expanded some number of times judging by the cracks.  It might have just been a thicker tooth.

 

When you photograph teeth, it's best to get one shot directly at both sides.  It's less helpful to collectors helping with ID's when a tooth is shot at even a slight angle though you can add extra views to focus on a particular feature.  A profile view (side view) also helps particularly when the possibilities are Carcharodon, and Parotodus.  That was a good idea to shoot a basal view (up at the root) - always a good view to add so we can see get some idea of the thickness of the tooth especially in the absence of a profile shot.