Fossil Info Requested

[Reighan]

Hi! I'm Reighan. I haven't posted until now because there hadn't been any cephalopods in the local glacial deposits I've been studying. (I'm a beginner.)

But this one seems to be an orthoconic nautiloid?

And then there is this, which looks like aragonite. Is it some kind of cephalopod?

Any comments will be appreciated! Thanks in advance.

 

[Reighan]

Ooops. I'll figure out how to resize pictures...

 

[cuttlegirl]

, I 'm not a fossil expert so I can't make any suggestions for you, but you've come to the right place!

 

[Reighan]

Thank you! There is a lot of very good reading here, so I'll be visiting frequently.

 

[Architeuthoceras]

Reighan.

The first photo is probably an orthoconic nautiloid as you thought, a little out of focus, but it looks like septa with some cameral deposits and a siphuncle.
I dont know about the fossil in the other 3 photos, it looks more like a crinoid stem than a cephalopod shell.

 

[Reighan]

Thank you, Kevin. The material from the glacial deposit is providing an unending educational experience. So far the crinoidal things have been Carboniferous calcite-in-limestone and some Ca-Mg impressions, so the aragonite would be a new one... Thanks again!

Reighan

 

[Phil]

Glad you made it over here Reighan, and welcome to TONMO.

Definitely a nautiloid that first one, and a nice find too. Was that your first from Wales?

 

[Reighan]

Hi, Phil

Just popped in and found this message. Sorry it took so long to respond. I've been bogged down with rocks and minerals. (BTW, the 'aragonite' in the non-ceph above is quartz .) (So much to learn...)
The nautiloid above was my first, and so far is the only one. Before I found that, we'd found only corals, crinoid bits, and brachiopods in Carboniferous limestone, which is why I noticed the nautiloid--because of the matrix! I'd never found anything at all in New Jersey, so the glacial drift on this beach is overwhelming (but wonderful). The more Mike & I learn, the more things we recognize and find, so... there are probably cephalopods out there somewhere. The most recent good 'un is a bit of chalk cidaroid.

ATB,
Reighan

 

[Phil]

Well, it may be your first, but it's certainly a good place to start! Well done! Keep going, you'll get a corker one of these days, trust me.

 

[Architeuthoceras]

It is possible that the other fossil is the silicified siphuncle of an Actinocerid.

 

[Reighan]

Thanks, Phil, for the encouragement.

And, thank you, Kevin, for the suggested ID. Sorry about my misidentified mineral. I Google-ed 'Actinocerid', and followed a lot of tangents, and learned quite a bit, so thanks for that as well.

ATB,

Reighan

 

[Phil]

I just tried to find a good basic description of Actinocerid nautiloids but to my horror found that the superlative website Paleos has been taken down for good! Oh no, this is terrible news.

I believe that the siphuncle is sub-ventral in these forms and tends to bulge out into each chamber like a inflated ring; these rings also contain heavy cameral deposits used as counterweights to control the orientation of the conch.

Hopefully Kevin will have a much better description.

 

[Reighan]

Thanks, Phil. That helps. Even considering my lack of knowledge, there didn't seem to be a lot of information on Actinocerids. Initially I got the impression they were all Australasian, which would have been a stretch even for this drift. But if mine is an actinocerid, then it's probably Silurian?

 

[aNmLlUvR09]

this is absolutely the most interesting message board i've ever been on...i dont understand half of what anyone is saying and its so thrilling!

 

[Phil]

Thanks, Phil. That helps. Even considering my lack of knowledge, there didn't seem to be a lot of information on Actinocerids. Initially I got the impression they were all Australasian, which would have been a stretch even for this drift. But if mine is an actinocerid, then it's probably Silurian?

Well, according to Clarkson's book the Actinceratina were a Suborder of Orthoceratid nautiloid that thrived from the early Ordovician (when most of the Orders and Suborders appeared) but became extinct in the early Carboniferous. I'm pretty certain that their distribution was global and I'm sure that examples of actinceratids have been found as wide afield as Utah, Japan and Europe. Rayonnoceras is a particularly well known form. Maybe it is worth asking which nautiloids are known from Wales on Joe and Lucy's site?

this is absolutely the most interesting message board i've ever been on...i dont understand half of what anyone is saying and its so thrilling!

Don't worry, old chap. I've no idea what people are talking about on here either most of the time, and I've been here for four years!