Ammonite

[drbush]

Hi friends ,can you help me with this ,I went to Aruma formation area (Cretaceous) to the north of Riyadh and found an ammonite , it is small , thin , 6.5 cm wide and 4 cm high , it was a surface find . what sp. could it be ?

[drbush]

[drbush]

[andreas]

I think it is similar to Tissotia or Hemitissotia .

[abyssunder]

I'm not an expert in ammonites, so I could be very wrong in the ID, but if the specimen was a surface find in the Aruma Formation, I suppose it was on the top of the Linah Member or, if the specific exposion of your locality has the top sediments eroded away, it may be from the underlying Hajajah Formation. If the latter is in case, you may have something similar to Manambolites (maybe M. amardi?) which was reported from the Hajajah.

Try to compare your specimen (especially the suture lines) with the specimen below, from MNHN.

 

 

 

[drbush]