Ammonite

[Notidanodon]

Hi guys, any thoughts on this one? Maybe a pseudocadoceras? I’m fairly sure it is from Ashton Keynes, making it callovian kellaways formation @Ludwigia  thanks!

 

[Tidgy's Dad]

It's rather  difficult as the outer whorls are so weathered and I can't see the suture well enough. 

But I don't think it's what you call 'pseudocadoceras', by which I presume you mean Pseudocadoceras. And Callovian and Kellaways. 

Notice that the more inner whorl has wide spacing between the ribs, but towards the venter they become thinner and closely-spaced. 

The outer whorl, just under the aperture shows closely spaced ribs. 

So maybe Sigaloceras ?

[Notidanodon]

1 hour ago, Tidgy's Dad said:

It's rather  difficult as the outer whorls are so weathered and I can't see the suture well enough. 

But I don't think it's what you call 'pseudocadoceras', by which I presume you mean Pseudocadoceras. And Callovian and Kellaways. 

Notice that the more inner whorl has wide spacing between the ribs, but towards the venter they become thinner and closely-spaced. 

The outer whorl, just under the aperture shows closely spaced ribs. 

So maybe Sigaloceras ?

Yes it does make it difficult, I was hoping the inner whorls were well enough preserved to be of use. I agree that fits better than my previous suggestion, I’m really more of a shark man myself haha. Here is another from the same location that I believe to be Pseudocadoceras

[Ludwigia]

Kepplerites is another possibility. The thinner whorl width seems to fit better and also the flat venter.

[fossils-uk]

The first is Sigaloceras calloviense and the second is Kepplerites tricophorous, both from the Kellaways Rock,

Calloviense zone, Callovian, Mid Jurassic .

Hope this helps.

[Notidanodon]

Thanks @Ludwigia and @fossils-uk that’s very helpful