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Friday, July 31, 2015

Edriocrinus policiformis crinoid "cup" from the Kalkberg formation of New York

These little Edriocrinus policiformis crinoid cups are somewhat common in the Kalkberg formation of New York. They are a pretty good indicator that the rocks are lower Devonian in age. These fossils are just the base of the crinoid calyx (which may have been free floating) and there were other plates attached that would extend the calyx up to the arms. They are fairly easy to ID as they look like small gumdrops that are hollow.

Specimen #1  - The first three photos in this sequence is viewing a profile of the calyx as I rotate it 120 degrees between shots.


This is the "oral" side of the cup.
This is the anterior or bottom of the cup.

This specimen is still attached to matrix and is a little taller than the previous specimen.




The Edriocrinus policiformis fossils I found in the Kalkberg formation compare nicely to those that I found in the Licking Creek formation of Virgina as seen here. The Virginia specimens are a little larger and "more complete" but have been replaced with silica. The Kalkberg formation is concurrent with the Licking Creek formation. Both are dated to the Lockhovian-Pragian stage of the lower Devonian. I found all the above specimens at a roadcut near Schoharie, NY.

Wednesday, July 29, 2015

Trilobites from the Kalkberg formation of New York

I have not found too many trilobite fossils in my limited searching of the Kalkberg formation but I did find pieces of two different species.

The first are these free cheeks from Acidaspis tuberculatus. Note the knobby extensions that are spaced along the edge of the genal spine up to where the cheek attached to the rest of the cephalon.




The other, major piece of trilobite that I found was this thorax-pygidium combo from what I believe was a Paciphacops logani.  I was very excited when I first spied this fossil lying on the surface of the rock. At the time the anterior was covered with some loose rocks but once I removed them only this remained. Since I found it in a road cut, perhaps it fell from a higher rock and landed on the bench I was exploring. It's too bad the cephalon was not with it as this would be a really nice specimen. As it is, a little light cleaning and I should be able to expose more of the exoskeleton.


It's a very thin fossil on a very thin piece of shaly limestone.

Both of these fossils came from the same roadcut near Schoharie, NY which exposed the Lockhovian to Pragian stage (Devonian) aged Kalkberg formation.

Monday, July 27, 2015

Kozlowskiellina perlamellosa brachiopod from the Kalkberg formation of New York.

This next fossil is one that always gives me trouble when naming it. Some refer to it as Kozlowskiellina and some as Delthyris. Both are very similar shells and appear to be valid names. The former seems to be confined to the Silurian and lower Devonian while the latter ranges from the Silurian up into the lower Mississippian (based on what I read on the Fossilworks.org website). The best reference found that lists the fauna of the Kalkberg formation (L.V. Rickard and D.H. Zenger. 1964. Stratigraphy and Paleontology of the Richfield Springs and Cooperstown Quadrangles, New York. Bulletin of the New York State Museum and Science Service 396:101) uses Kozlowskiellina perlamellosa and that is what I will settle on as the name for this brachiopod fossil.

Kozlowskiellina perlamellosa is a half moon shaped shell with a straight hingeline. Both valves are covex and roughly equal in size with the pedicle valve being slightly larger. The pedicle valve recurves back and mostly covers a small delthyrium. The surface of the valves have strong ribbing which in turn has prominent growth lines.

Brachial valve
Anterior
Pedicle valve
Posterior
Profile

This fossil was found in a road cut near Shoharie, NY in the Kalkberg formation (Lower Devonian, Lockhovian to Pragian stage).

Saturday, July 25, 2015

Machaeraria formosa brachiopod from the Kalkberg formation of New York

This specimen, that I collected from the Kalkberg formation of New York, has given me some trouble trying to identify it but I think I've narrowed it down to Machaeraria formosa. I'm basing this due to the description by Hall in "Paleontology of New York", Vol III part 1, page 236:
SHELL subtriangular or transversely oval; lateral margins forming an angle at the beak of about 90° to 110°. Ventral valve somewhat more depressed than the opposite: beak prominent, arched, not strongly incurved. Dorsal valve larger, declining with a gentle curve towards the margins: beak incurved.
SURFACE marked by twenty to twenty-four simple angular plications on each valve, from two to four of which in the middle are coarser and depressed in the ventral valve, having a corresponding number abruptly elevated upon the dorsal valve; concentrically marked by fine closely arranged striae.
Hall's originally named the species Rhynchonella formosa in the aforementioned 1859 publication but that appears to have since been updated to Machaeraria formosa based on Karl Wilson's 2014 book "Field Guide to the Devonian Fossils of New York".

Brachial valve
Anterior
Pedicle valve
Posterior
Profile

The Kalkberg formation is lower Devonian in age (Lockhovian to Pragian stage). I collected this specimen from a roadcut near Shoharie, NY.

Thursday, July 23, 2015

Mesodouvillina varistriata brachiopod from the Kalkberg formation of New York

I recognized today's fossil very quickly due to it's similarity to specimens I have collected from the Givetian stage of the Devonian. This is Mesodouvillina varistriata from the Kalkberg formation of New York. It is a Strophomenid type brachiopod which means that the pedicle valve is convex while the brachial valve is concave. The most identifying feature is the decoration of the shell surface with fine striae which have even finer intermediate striae between them. Otherwise the shell is roughly rectangular in shape with a straight hinge line that is wider than the shell is long.

Pedicle valve
Anterior
Posterior
Profile

The Kalkberg formation is lower Devonian in age (Lockhovian to Pragian stage). I collected this specimen from a roadcut near Shoharie, NY.

Tuesday, July 21, 2015

Discina sp. inarticulate brachiopod from the Kalkberg formation of New York

The specimen below is the only one of any kind of inarticulate brachiopod that I found in the Kalkberg formation of New York. It is fused to the shell of an articulate brachiopod (an orthid of some type perhaps) and is somewhat weathered. From what I can see it is round to oval shaped along the margins with the dorsal valve broadly conical and having a central apex. The specimen has been weathered enough to remove most of the surface ornamentation which would help to identify it down to species level but I do see some very fine concentric growth lines. There also appears to be some mimicking of the shell structure upon which is has cemented itself along one edge. Hall does not list many inarticulate brachiopods as coming from the lower Devonian rocks of New York, however he does list several species under a genus called Discina in "Paleontology of New York", Vol III part 1, page 159-162. Hall also mentions that other workers has ascribed similar looking specimens to Orbiculoidea which is in the same family as Discina. For now I am calling this specimen Discina sp. until I can clean it to find more detail or otherwise determine it to be a different genus.





The Kalkberg formation is lower Devonian in age (Lockhovian to Pragian stage). I collected this specimen from a roadcut near Shoharie, NY.

Sunday, July 19, 2015

Howella cycloptera brachiopod from the Kalkberg formation of New York.

I found several specimens of Howella cycloptera from the Kalkberg formation of New York for my collection. The shell has a flat hinge line with a semicircular shape along the margin. Both valves are inflated with the pedicle valve equal to or deeper than the brachial valve. A simple ridge and sulcus is present on the brachial and pedicle valve respectively. There are about seven round plications on either side of the ridge/sulcus on the surface of both valves with some some fine concentric growth lines present as well. Were there to be more plications then this could be Concinnispirifer concinnus but none of the specimens I collected have that many.

 Brachial valve
Anterior
Pedicle valve
Posterior
Profile

The Kalkberg formation is lower Devonian in age (Lockhovian to Pragian stage). I collected this specimen from a roadcut near Shoharie, NY.

Friday, July 17, 2015

Uncinulus sphaeroidalis brachiopod from the Kalkberg formation of New York

This little, round, marble like brachiopod is Uncinulus sphaeroidalis from the Kalkberg formation. It can be distinguished from similar Uncinulus species by the roundness of the shell when viewed in profile or from the front or back. Both valves are convex and have coarse plications with a slight ridge/sulcus but they only have a subtle effect on the shape of the shell. The sulcus and ridge are most expressed along the anterior margin as it angles up over and then back down at a near 90 degree angle.

Specimen #1 - Brachial valve
Anterior
Pedicle valve
Posterior
Profile

Specimen #2 - Brachial valve
Anterior
Pedicle valve
Posterior
Profile

Both specimens were collected from the Kalkberg formation of New York, which is lower Devonian in age (Lockhovian to Pragian stage), near the town of Shoharie.

Wednesday, July 15, 2015

Hindia sphaeroidalis sponge from the Kalkberg formation of New York

Sponges are not something I typically look for while collecting but some of the specimens of Hindia sphaeroidalis that I found in the Kalkberg formation of New York were nearly the size of a ping pong ball! I know that Hindia is a somewhat common sponge from the Ordovician up through the Devonian but these are the first specimens I have found. H. sphaeroidalis forms a round sphere or ball shape with no one particular surface being an obvious "top" or "bottom". I suspect this is because it rolled with the waves or currents on the sea floor rather than secure itself to a single spot. Other than the round shape, the only other way you can recognize this fossil is the granular surface which is in contrast to the typically fine, smooth limestones of the Kalkberg.

Specimen #1



Specimen #2 - with some matrix still attached.






Specimen #3 - This is an odd one in that it is somewhat flattened but it does not appear to be the result of compression.



Here are the three above specimens in a side by side shot to show the variation in size.

Specimen #4 - This is the only specimen I found with any sort of mark or area that broke the round surface. The dimple shape on this specimen is unusual and might be the result of the specimen growing next to another of it's species. I do not think it is a different species or genera as there are no other indicative markings to be found and the rest of the specimen conforms to the generally spherical shape know for H. sphaeroidalis.


The Kalkberg formation is lower Devonian in age (Lockhovian to Pragian stage). I collected this specimen from a roadcut near Shoharie, NY.