Wednesday, December 17, 2014

Glyptogypa multiplicata brachiopod from Morocco

I've been wanting to get some Devonian fossils from Morocco that were not trilobites for some time now. My thought was that they had to exist out there in the desert but that they weree just being overlooked by the collectors since they could make more money selling trilobites. Lucky for me that I stumbled upon a dealer on Facebook who did have some brachiopods from Jebel Issomour for sale and I snapped them up.

This is  Glyptogypa multiplicata and comes from rocks dated to the Eifelian stage of the Devonian period.

Specimen #1
Pedicle valve
Anterior
Pedicle valve
Posterior
Profile

Specimen #2
Brachial valve
Anterior
Pedicle valve
Posterior
Profile

I identified this fossil based on the paper:
Middle Devonian brachiopods from the southern Maïder (eastern Anti- Atlas, Morocco). Halamski, A.T. and Baliński, A., 2013. Annales Societatis Geologorum Poloniae, 83: 243–307.

Thank you Odou for these fossils!

Monday, December 15, 2014

Cupularostrum prolificum brachiopod from Arkona

Today's fossil was found by accident after a practical joke my a friend I was collecting with. We had been collecting for several hours and been disappointed by the lack of Trilobites. One member of the group suddenly called out to us that he'd made the "find of the trip" which of course got us all scrambling over to see what it was. When we got there it turned out to be a piece of a shoe and was not at all worth the effort. While I was admonishing the perpetrator of the prank I noticed a fossil sitting on an eroded pedistal that caught my eye. A closer inspection revealed it to be an articulated Rhynchonellid brachiopod and one that I think is a Cupularostrum prolificum similar to that which is found in the Silica Shale.

Brachial valve

Anterior
Pedicle valve
Posterior
Profile

This fossil was found among debris that was exposed from a cliff fall along the Ausable river near Arkona, Ontario. I believe it came from the Widder formation, Hungry Hollow member (Devonian, Givetian stage).

Saturday, December 13, 2014

A new specimen of Productella spinulicosta from Arkona

Another cool fossil find from last fall at Arkona is this Productella spinulicosta brachiopod with some of the spines still intact. I found it on a weathered slope that exposes both the Widder and Arkona formations (both are Devonian, Givetian stage) so I can't say for sure which set of rocks it came from. Previously I've only found specimens of this species with no intact spines.




Thursday, December 11, 2014

Playtceras spinosum gastropod on Arthrocantha crinoid calyx from Arkona

About three years ago I posted some pictures of a Platyceras sp. gastropod that was fossilized on top of an Arthrocantha sp. crinoid calyx that came from the Silica shale in Ohio. This past fall I found a similar fossil at a site near Arkona, Ontario, Canada. The specimen came from a weathering pile of Arkona shale (Devonian, Givetain stage) and was found on the surface.  The gastropod has a few circular openings on it's shell that I interpret as being the bases for spines so I should label it as Platyceras spinosum.

 






There are a couple of bryozoan epibiont patches on the Platyceras shell as well but I am unsure of the species.


Tuesday, December 9, 2014

Scalaripora canadensis bryozoan from the Arkona formation

A couple of years ago I found a small, isolated specimen of Scalaripora sp. from the Arkona formation. On a visit this past fall I found two more pieces that are larger than that first piece. Both have the same thin, tripartite growth pattern but there is enough present that I think I can narrow the species down to S. canadensis. I base this upon reading an old text: "Contributions to Canadian Palæontology, Volume 1" By Joseph Frederick Whiteaves, Montreal, 1885.  Page 378 has the following description and plate 48 has an illustration. 
"Zoarium consisting of stems that are triangular and almost equilateral in transverse section, the broadest of the three faces having a maximum diameter of about 7.5 mm, and the narrowest of 6.5 mm. Faces shallowly concave or nearly flat: angles acute forming three sharp, prominent, and nearly straight but rather irregular, longitudinal ridges. Transverse ridges distant, nearly as far apart as the faces are broad, not continuous in either of the two fragments examined, developed (or present) on two of the faces in the longer of these fragments, and on only one face in the shorter. Whole surface celluliferous, apertures averaging from about 0.16 mm to 0.25 mm in diameter, usually rather more than their own diameter apart, or about equal to it in distance, subcircular with a slightly elevated annular peristome and arranged obscurely in more or less regular diagonal rows, seven or eight in three mm. Internal structure not observed. "

Specimen #1







Specimen #2