Fossil ID help: Knightia, Shark tooth (hastalis or desori), Ammonite (Aioloceras?)

[Praefectus]

Hello. I was wondering if anyone could help me with some fossil identifications. Thanks for any help. 

 

 

First, here is a Green River formation fish plate. I know the fish are Knightia, but I don't know how to differentiate the species. I think they are Knightia eocaena. Can anyone confirm the species? Thanks.

 

 

 

Next, here is a shark tooth I found while digging on the Ernst ranch in Bakersfield, California. It is either Carcharodon hastalis or Isurus desori. I'm not great at telling the two apart. Can anyone confirm the species? Thanks.

 

 

Last, here is an ammonite I received from caldigger. He identified it as Aioloceras besiaiei. I think the species might have been misspelled and is supposed to be besairiei. I've seen these sometimes referred to as Cleoniceras. Does anyone know the difference between Aioloceras and Cleoniceras? Thanks. 

 

[Fossildude19]

Fish are definitely Knightia eocaena. 

[PrehistoricWonders]

The mako looks like a hastalis, but could be planus, almost definitely not desori. Agreed with @Fossildude19 on the fish.

[Praefectus]

Thanks for the fish ID @Fossildude19

[Praefectus]

2 hours ago, Familyroadtrip said:

The mako looks like a hastalis, but could be planus, almost definitely not desori. Agreed with @Fossildude19 on the fish.

Hi @Familyroadtrip. The shark tooth generally fits the shape of either Carcharodon hastalis or Isurus desori. It is not as wide as other Carcharodon hastalis teeth found at Bakersfield, but the root is a bit square for Isurus desori. It is not “hooked” enough for Carcharodon planus. Below is a comparison picture of some teeth that I am sure about the ID on from the same trip.  

 

 

[BellamyBlake]

I think the shark tooth is Isurus planus.

 

Edit: After seeing your comparison @Praefectus, I'm inclined to say Isurus desori.

[PrehistoricWonders]

Isurus desori has more of a root that bulges, and the tooth in general is thicker(at least with mine) your desori tooth looks more like a lower hastalis to me. I’m not an expert though, so I definitely could be wrong, but that’s just my experience.

[FossilDAWG]

If you check this thread you will find a post where I gave the reference to the paper by Kennedy & Klinger that changed Cleinoceras besairie to Aioloceras besairie. 

 

Don

[Praefectus]

42 minutes ago, FossilDAWG said:

If you check this thread you will find a post where I gave the reference to the paper by Kennedy & Klinger that changed Cleinoceras besairie to Aioloceras besairie. 

 

Don

Thanks for the help! The thread was an interesting read. I will give the paper a read later tonight.