U.mississippian Chesterian Shark Worl

[Archimedes]

This unusual form was found in the Bangor Limestone

and is 7/8 inches by 5/8 inches

Any Idea of its taxonomy

[Gatorman]

I donno what it is but its really awesome looking.

[geofossil]

I'm not familiar with the Bangor Limestone but your specimen 'resembles' that of the whorls of 'Sibryhychus (spelling?) which is classified with the iniopterygian . This Upper Carboniferous beastie has various dentition shapes that can fool you into thinking the finds are from different species. Zangerl has an attempt at reconstruction of a dentition in one of his publications. If I can find it, I'll scan a photo.

[Archimedes]

geofossil,

Yes I would like to see a picture from Zangerl

and know the publication it is from so I might get a copy.

I have very little literature on paleozoic shark.

I have named it the Moose Horn.

[Guest N.AL.hunter]

We have a lot of bangor limestone around here, so I must now keep a closer eye out!

[geofossil]

This unusual form was found in the Bangor Limestone

and is 7/8 inches by 5/8 inches

Any Idea of its taxonomy

Re Sibyrhynchus

Here's a drawing originally in a Field Mueum publication by Zangerl and Case...it's also reproduced in Case's fossil book and in Philipe Janvier's excellent recap of early fossil Vertebtates (M.N.d'Histoire Naturelle).

The Bible of Fossil Shark publications is Woodward's 1889 publication 'Fossil Fishes part 1 Elasmobranchii' of the British Museum of Natural History....it list's all curated specimens to that date (several thousand) with many illustrations. Armed with that, the Russian Treatise on Vertebrates from the 1960's and Philipe Janvier's summary , you can start to get a handle on this elusive group of Paleozoic fossils. About a decade ago I did a paper on the Lower Carboniferous Fossil Shark teeth of the Banff Formation and researched the literature quite extensively. I managed to access about 80 papers. One soon realizes that about 90% of the literature is tooth description and no body to hang it on.. There's lots of elbow room for more research into these shark ancestors.

The whorls in the mouth region vary in numbers of points, width, height and so on. They way they all fit together is subjective reconstruction. These type of specimens are found in various Upper Carboniferous formations around the world but the same 'general' shapes are found with differences in size, spacing and so on.

[Archimedes]

Thank You geofossil

I will start looking for these books/papers

and look up the Banff Formation

the only real literature I have on paleozoic shark is the

Illinois Geological Survey 1-8 1870s-1880s

[geofossil]

Thank You geofossil

I will start looking for these books/papers

and look up the Banff Formation

the only real literature I have on paleozoic shark is the

Illinois Geological Survey 1-8 1870s-1880s

I have that one also. Some of those 19th century publications are not only helpful but are works of art iin themselves.

I lucked into the Woodward book when in the UK...it's a 'ratty' specimen but all there. It's well worth looking out for in on the Internet. The Russian treatise is what we used the most for reference. The Carboniferous and Permian fossil province runs from Russia north into the Canadian Arctic and down Western Canada into the western USA. The Carboniferous in the Eastern USA has 'similar' fauna but not as closely related as the north-south connection. Of course, the 'north' 'south' and so on is only today's reference as the continental plates have changed location over the last 300 million or so years since the Carboniferous. Probably, however, like today,mobile fauna like sharks were more worldwide and restricted by water temperatures more than continental masses.