Belemnite species

[Ossicle]

Following on from a post in the questions forum, I was trying to identify this species of belemnite that I picked up on Friday from the Oxford Clay at Whittlesey, and learn generally how to identify species myself, rather than squeak 'thunderbolt' excitedly. It struck me as unusual partly because its shape is different from most of the belemnites I see in the Oxford Clay, but also because of the strange white coating. Aragonite is preserved at the site, and I thought perhaps it had aragonite around the calcium carbonate rostrum. Sadly it broke as I extracted it from the clay. It is conical, depressed, very acute and has a deep groove.

 

I was using Fossils of the Oxford Clay to identify it, but although it is most similar to Belemnopsis bessina, I then decided it couldn't be because it is not hastate. But rereading the description it does say it can be weakly hastate, and it might be. Also in favour of this specimen being this species is the flattened apex and kidney shaped transverse section caused by the deep groove. I was possibly overthinking things. It would be reassuring to have other people's input  

 

Other features include a strange ridge on the reverse. Not seen that before.

 

Also, just for fun, an 8mm belemnite. I'm not expecting to ever identify it, but it's cute and I thought I'd share.

 

 

[Ossicle]

And baby belemnite

[Fossildude19]

@TqB  

[TqB]

Hi, You're right with Belemnopsis bessina, "weakly hastate" describes that specimen perfectly. A good specimen too, about as big as they come in the UK.

I'm not sure about the strange ridge you mention, it looks like a streak of matrix, perhaps pyritised.

 

The chalky surface is a result of weathering - it doesn't happen in all specimens but, in my experience, is common in otherwise well preserved ones from clays. I don't think it was aragonitic as belemnite rostra were usually mostly calcite originally.

 

How big (or small!) is the juvenile? It's almost certainly Cylindroteuthis puzosiana.

Edit: just saw that you said 8mm, lovely little specimen. Most people leave them which is a pity!

[westcoast]

Alveolar canal?

[Ossicle]

Thank you, that makes me a lot more confident if I apply myself I can distinguish species. I'll go over the ones I have already collected from this site and try to classify them. I too often leave a good specimen not knowing if it is a particularly fine example or rare, because of the sheer number of them at the site. Then I grab some at random because they are still fantastic. And if I collect the small ones I might learn a bit about their development too.