Monday, December 31, 2012

Staufenia sp. ammonite from Germany

A friend of mine, Roger, from Germany was in Canada visiting some of his family recently and I was able to meet up with him and do some trading. He primarily collects from his local Mesozoic exposures in southern and central Germany. I swapped some Trilobites with him and in return he gave me some Ammonites that he'd personally collected and prepped. This cut and polished specimen is a Staufenia sp. (possibly S.sinon or S.opalinoides). It is a beautiful specimen with some of the chambers filled with calcite crystals.




Back of the specimen

Some of the suture lines are visible through windows in the matrix.



This specimen came from near Scheffheu in the Wutach Valley of the Black Forest, Germany. As with most ammonites, it's stratigraphic position can be precisely placed. In this case it's the Staufensis Bank, Bradfordensis Zone, Achdorf Formation, Upper Aalenian, Middle Jurassic. This is the last of the specimens that I received from Roger and it seemed appropriate to end 2012 with these beautiful fossils. If the Mayan calender turns out to be wrong I have many more fossils to blog about in 2013!

Happy New Year!

Saturday, December 29, 2012

Pleuroceras transiens ammonite from Germany

A friend of mine, Roger, from Germany was in Canada visiting some of his family recently and I was able to meet up with him and do some trading. He primarily collects from his local Mesozoic exposures in southern and central Germany. I swapped some Trilobites with him and in return he gave me some Ammonites that he'd personally collected and prepped. Below is a Pleuroceras transiens ammonite from the Lias delta beds (lower Jurassic, upper Pliensbachian stage) near Goldbach, Germany.




Thank you to Roger for giving me this cool fossil. It's a nice comparison with Pleuroceras spinatum.

Thursday, December 27, 2012

Parkinsonia parkinsoni ammonite from Germany

A friend of mine, Roger, from Germany was in Canada visiting some of his family recently and I was able to meet up with him and do some trading. He primarily collects from his local Mesozoic exposures in southern and central Germany. I swapped some Trilobites with him and in return he gave me some Ammonites that he'd personally collected and prepped. The specimen below is a Parkinsonia parkinsoni ammonite from the Parkinsoni-Zone, Dogger epsilon, Bajocian stage, Jurassic of Sengenthal, Germany.




Thanks to Roger I now have my second Ammonite from Sengenthal, here is my first.

Sunday, December 23, 2012

Graphoceras concavum from Geisingen, Germany

A friend of mine, Roger, from Germany was in Canada visiting some of his family recently and I was able to meet up with him and do some trading. He primarily collects from his local Mesozoic exposures in southern and central Germany. I swapped some Trilobites with him and in return he gave me some Ammonites that he'd personally collected and prepped. The specimen below is a Graphoceras concavum ammonite. I like that you can still see some of the surface decoration, in the form of gentle waves, along with some of the suture pattern of the internal chambers.





Graphoceras concavum is the index fossil for the Concavum Zone within rocks that are dated to the Upper Aalenian stage of the Middle Jurassic within Europe. Roger found this specimen in the "Geisingen-Oolith" at the clay pit in Geisingen, Germany. My thanks to Roger for giving me this wonderful specimen!

Friday, December 21, 2012

Dactylioceras commune from Yorkshire, England

A friend of mine, Roger, from Germany was in Canada visiting some of his family recently and I was able to meet up with him and do some trading. He primarily collects from his local Mesozoic exposures in southern and central Germany. I swapped some Trilobites with him and in return he gave me some Ammonites that he'd personally collected and prepped. Among them are these two Dactylioceras commune from near the town of Kettleness along the Yorkshire coast of England.

The first specimen is completely exposed, except for a minor piece of matrix on the back.



The second specimen is still embedded within the limestone nodule that they are typically found in. Roger cut and polished a face to exposed the preserved chambers within.


Here you can see the exterior of the nodule (polished side is at the top) and notice that there is another specimen still within the rock.

These specimens come from the bifrons Zone of the Lias epsilon within the Toarcian stage of the lower Jurassic (now that is some specific stratigraphy!). A big Thank You to Roger for giving me these specimens!

Wednesday, December 19, 2012

Onnia superba Trilobites from Morocco

I purchased the specimen below from E-bay because the fossils looked very clean and with little restoration. There was no label included beyond "Onnia, Morocco" but a little searching on Paleodb.org gave me this: late Ordovician (Ashgill or Hirnantian stage), Ktaoua Grp, Upper Ktaoua Fm., Anti-Atlas Mountains, Morocco. This appears to be the same group that the Flexicalymene ouzregui I profiled earlier comes from but must be from a different horizon since the matrix is limestone rather than mudstone concretions.









These guys look very much like Cryptolithus sp. trilobites that are found here in North America but they are called Onnia superba when they come from Morocco.

There is an interesting paper available here: The Stratigraphical Distribution and Taxonomy of the Trilobite Onnia in the Type Onnian stage of the Uppermost Caradoc which has quite a bit of info and pictures of the species.

Monday, December 17, 2012

Harpes sp. trilobite from Morocco

This is the cephalon of a Harpes sp. trilobite from the Middle Hamar Laghdad Limestone near Tafilalt, Morocco. It's only a partial but displays the prominent flattened margins around the cephalon. I purchased it from Geological Enterprises as a reference piece of what a non faked Moroccan trilobite can look like. The specimen is not perfect with part of the glabella ground off but otherwise there is little restoration.





Based on the web site Paleodb.org the Middle Hamar Laghdad Limestone is lower Devonian (upper Emsian) in age

Saturday, December 15, 2012

Flexicalymene ouzregui trilobite from Morocco

A couple of years ago I purchased a few the mud ball trilobites from a member on the Fossil Forum site. There wasn't much information on who, what or where they came from (other than Morocco) but they make for nice display specimens. Most of the specimens that I've seen for sale are loose, single trilobites that have poor preservation (such as these posted on E-bay). There are a number of different names associated with these trilobites as well with most being called "Calymene" or Flexicalymene". The pieces I purchased were whole nodules that had been cracked open.

First up are a couple of pictures of the exterior of the nodule they fossils are found in.

They have to repair them once broken and this particular one had a coating of another clay to make it look more homogenous and not fractured. I washed it off in favor of the natural look.

Inside is a nice positive and negative of a large Flexicalymene type trilobite. No additional paint or touch up was applied to the fossil, this is exactly how it looks.





After a quick search of the interwebs I found an answer to the species and location of these mud trilobites: Flexicalymene ouzregui
Anti-Atlas Region
Tazzarine des Aït-Atta, Tarhbalt (Maïder)
late Ordovician - Ashgill (lower) (Hirnantian stage of ICS)
Ktaoua clay and sandstone group
upper argillite formation

Thanks to "Pirhana" a member of the Fossil Forum site for posting the useful info.

Thursday, December 13, 2012

Proetus (Gerastos) granulosus trilobite from Morocco

These nest two specimens came to me via two separate auctions on E-bay. The first was purchased as "Phacops granulosus". The second came from Sahara Imports and was labelled "Gerastos". It's taken me a little digging but I've found more instances of Proetus (Gerastos) granulosus (from the AM Limestone, Mt. Issoumour near Alnif, Morocco) than Phacops that match the trilobites that I have.

As this is a Proteid trilobite it should have holochroal eyes, but I've not seen any specimens that ever show the many lenses that should be evident. It's a cheap (good specimens can be had for under $25) fairly common species so I can't believe anyone would waste their time trying to fake them.


Specimen 1








Specimen 2