Have you found a good fossil ceph? Or any other fossil you would like to share with us? Tell us all about it!

Here's a chap who has found more than a few...

http://www.wcfcourier.com/lifestyles/030411shells.html

(thanks, Tony)

Sorry... Just a fossil clam given to me by an old friend... :P

Sushi and Sake,

John

all i have as far as fossils are concerned are just bivalve pieces and some augers...not really exciting, dont knowq much about them and theyre not cephs.... :|

Here is a fossil I found, from the Ordovician (about 450 mya) of Utah. You can see why they call Nautilus a living fossil. This is Plectolites, at least a fossil of the shell. Most of the chambers were broken and got filled with seafloor sediment, the left side is missing altogether. The chambers in the very center were still hollow when the sediment was turned to limestone, and latter the void was filled with calcite crystals, this destroyed the septa. The Siphuncle is a little different than in Nautilus

A fairly large file (196K) for detail

:ammonite:

Wow! That's a beauty!

It's amazing to thing how similar this nautilus is to the modern species. I wonder which group of nautiloids it belonged to? According to my references the order of nautiloid that gave rise to our modern species did not appear until the early Devonian. So if yours is from the even more ancient Ordovician then it must belong to a separate long extinct nautiloid order.

Yet it is so similar! Amazing. I'll see if I can find out some info on Plectolites.

Phil

Fossil Goniatite shells with an orthocerid nautiloid. Mississippian (Early Carboniferous) about 320 mya.
:ammonite:

That is a fantastic find.......do you find stuff like this regularly? Do you keep the fossils or sell them on?

Totally jealous!

Yeah, seriously 8) -- how and when did you find that one?

Hi Guys!
The Goniatites are all in a single concretion. I found it in a wash after a gully-washer washed it out. It is the only concretion of that age I have found that still shows the nacreous luster of the original great-great-grandmother of pearl. I watch the National Weather Service page all the time and if I see a good storm go over that area, then I go see if any more wash out.
I usually keep the good ones an leave the others for other collectors. They are found on US Public Land (BLM) so I can only collect them in reasonable quantities, for personal use, and cannot sell or trade.
:ammonite:

It's hard to take a picture of the nacre in normal light, so I took a picture of a small piece of broken shell from the same concretion, then took a picture under the microscope with the light just right to show the colors. This is a piece of shell from Goniatites multiliratus, you can see the small ridges (lirae) that gives it it's name.

If anyone is wondering why these ammonoids do reflect the light so beautifully as demonstrated in Kevin's picture above, it is because the shell of the ammonoid was composed of alternating layers of aragonite and conchiolin. The mantle secreted each layer as the creature grew and added chamber following chamber to its shell. Aragonite, composed of vertical prisms reflected light at a different wavelength to the conchiolin below. With four or five layers this means that intact shells of ammonoids often exhibit a rather nice subtle rainbow effect.

Ammonoids are found in many different colours, but this is an artefact of the type of mineral that precipitated into the gaps in the cells of the creature during the process of fossilisation. So a greenish ammonite does not necessarily mean that was the colour of the creature when it was alive. It seems highly likely that the ammonoid would have employed some form of countershading as a defense, much like the nautilus, though the exact form of which is anyones guess!

Thanks for that great explanation Phil,

Here is another picture from the same concretion, I believe this is a shell fragment from an orthocerid nautiloid. I don't know why but it seems the fragments are alot more colorful than the shell on a complete fossil.
:ammonite:

Can anyone help me out with this ammonite. It is unlocalised (was just given to us yesterday). I'd love to know what it is (genus maybe, if possible), how old it is and where it has come from (if any of this is possible). It could have come from New Zealand, but it could have come from Mars.

It is rather distinctive. It's greatest dimension is 24cm (to the end of that pretty bizarre spike). Oooops, Phil has just corrected me - 'spike' = lappet. I should stick to squid and octopus :D

Cheers
Steve

Steve,

I found another lappet-bearing ammonite, online. Of course, the image was posted sans identification, but it makes for an interesting comparison with your new fossil. You can see the outline of the bisected lappet in the stone, extending to the edge of the photo.

Clem

ps: I had no idea the proper term was "lappet," either.

Thought I'd post another image of some more stunning ammonites that have 'turned up' on the desk of late.

Upper left: Phylloceras sp. Albian (Cretaceous), Madagascar.

Lower left: Lamberticeras sp. Upper Calvian (Jurassic), Russia.

Lower right: Hoploscaphites nicolletii. Fox Hills formation, South Dakota (Late Cretaceous)

Upper right: Desmoceras cf. mahabobokensis, Albian (Cretaceous), Madagascar.

There are some other truly stunning bits and pieces, images of which I'll post another time (they're actually in the display cabinet at home :madsci: ). I really have been spoilt lately.

Cheers
O

Oooops, Phil has just corrected me - 'spike' = lappet. I should stick to squid and octopus.

Looking at this again actually I think that this form of spike on the aperture is called a spine. How original! :oops:

Lappets were lobes that projected from either side of the aperture, so I was completely wrong. I should stick to watching TV from the seventies!

Still not having much luck in identifying the specimen, hopefully when I get this CD-Rom on fossil Mollusca soon it may be on there.

Quoting most of this out of the treatise: A ventral extension of the peristome (apertural margin) may form a ventral lappet; or the ventral extension may be developed as a long, tapering rostrum.
More common are the paired lateral lappets.
As for an identification, Mortoniceras of the Early Cretaceous has the same kind of mature modification, but it has strong ribs covering it's shell. Pectinatites from the Late Jurassic also has a rostrum like that but it has ribs also. The fossil looks alot like Oxytropidoceras from the Cretaceous, but I don't know what the mature aperture looks like. Need more input for better I.D., any sutures visible?
The other fossils are great, do you have I.D.'s and locality info. on them?

Upper left: Phylloceras sp. Albian (Cretaceous), Madagascar.

Lower left: Lamberticeras sp. Upper Calvian (Jurassic), Russia.

Lower right: Hoploscaphites nicolletii. Fox Hills formation, South Dakota (Late Cretaceous)

Upper right: Desmoceras cf. mahabobokensis, Albian (Cretaceous), Madagascar.

do you have I.D.'s and locality info. on them?



Duh!!!!! :oops:

As for an identification, Mortoniceras of the Early Cretaceous has the same kind of mature modification, but it has strong ribs covering it's shell. Pectinatites from the Late Jurassic also has a rostrum like that but it has ribs also. The fossil looks alot like Oxytropidoceras from the Cretaceous, but I don't know what the mature aperture looks like. Need more input for better I.D., any sutures visible?

Kevin, Phil, Clem, I'll get back to you on this one, but it will be a couple of days away (full swing on something else right now). The shell has many apparent low-profile/gently undulating ribs, but no sutures are apparent. Ta for the input. It's great having a fossil forum!!
Cheers, O

Here are some pictures of an excavation I did a few years back. You can see a map of the excavation at this link "map" (http://ammonoid.topcities.com/anamap.htm)
The old guy in the picture is me. These are ceratitic ammonoids from the Early Triassic, approx. 240mya, the first picture shows a closeup of one of the sutures.

Enjoy :ammonite:

The concentration of fossils is quite incredible, and all a decent size too!

Having worked as an archaeologist it is quite interesting to see that the method of recording distribution of finds is practically the same. We used to lay out a large grid frame on top of a section of a trench and used a plumb-bob to record depth of the objects one would record. This was, of course, in order to plot features and finds so that they could be tied into the overall site plan. I suppose the only real difference with palaeontological plotting is that it is primarily finds orientated whereas with archaeology everything has to recorded from soil horizons to cuts, pits, features, structures and, of course, finds.

I used to love doing that; it really brought out the old artistic skills!

That ceriatite clearly demonstrates how simple the sutures were in these early ammonoids. The later ammonites had much more complex sutures; this 'fingerprint' is unique to each individual ammonite species. I wonder if ceriatites demonstrate a similar diversity? (They must be harder to identify on a species level as the suture is so simple, methinks).

Do you publish your excavation reports, Kevin? (By the way, your web-site is great!)

Thanks Phil,

It seems computers have made publishers out of everyone, but I have only co-authored a small article about some fossil sponges I found in the same formation as the ceratites.

Species ID on the triassic ammonoids depends on how specific you want, or need, to be. Most triassic ammonoid sutures are almost identical, shell shape and ornamentation are usually different enough for generic IDs. Being a lumper at the moment let's me group all those ammonoids into two species of two genera, those with ribs, and those without.

I am working on a vertical section thru the beds, will post pictures when I have them, in a few months?

:ammonite:

Looking forward to this Kevin
Cheers
O

thought people might find this interesting...

http://www.cnn.com/2003/TECH/science/06/26/fossil.park.ap/index.html

I have finished the vertical section and posted it to my web page (http://ammonoid.topcities.com/anasection.html). The attached picture shows the section and outlines of all the fossils.
:ammonite:

Kevin,

Apologies about the delay in replying.

I was curious to know if you have found any other organisms apart from sponges, ceratites and occasional nautiloids in these deposits, and if you could draw any inferences as to the marine habitat these creatures existed in. I'm really thinking of details such as depth, and whether or not this was a coastal deposit, or one on the continental shelf at the time?

The deposits seem to be very rich indeed. Is this an artifact of a specific event or series of events? For example, is the apparant mass mortality due to a mud slide that gathered up these creatures and deposited them together? Or are these depositions at a natural background mortality rate?

Very interesting stuff!

Phil

P.S. Mind the rattlers!

I'm Working on a small background document to go with the other pages I have about these fossils. I'll let you know when it's finished (shortly) and then maybe I'll open the whole thing up for debate.
:ammonite:

Iv never found a fossil yet.

Here are pictures of two specimens of an undescribed ammonoid I found while on vacation in the desert last week. I think they are a form of Kazakhoceras. I took the picture of the sutures with the fossil under water so they would show up better. They are from the Late Mississippian age (Late Early Carboniferous) or about 330my old.

:ammonite:

I wonder how rare this particular ammonoid is?

I'm afraid that I have failed to find out any information on Kazakhoceras, none of my resources mention the thing at all, I'm afraid.

However, have you seen this? I discovered it whilst attempting a search on goniatites. It is a downloadable database called 'Goniat' by Prof. Jurgen Kullman and is an extremely detailed resource on these creatures. Despite downloading all the files I could not get the thing to work, but you may have more luck than me!

Goniat: Palaeozoic Ammonoid Database System (http://www.uni-tuebingen.de/geo/gpi/mitarbeiter/kullmann/seiten/goniaten.html)

Phil, I've been using GONIAT for almost 10 years now. Make sure you have a directory structure like it shows in the readme file. The new windows version is harder to figure out than the old dbase runtime version. A great program that has info on every species of described paleozoic ammonoid, I would be lost without it. There are suture figures for two species of Kazakhoceras but neither match the specimens I have exactly, and all six described species are a little younger (about 320-329my old).

:ammonite: