Leptestia sp. brachiopod & Cryptocrinites sp. cystoid from St. Petersburg

I'm always on the lookout for new brachiopods for my collection and this Strophomenid type caught my eye when posted on E-bay. It's from the Ordovician aged rocks near St. Petersburg in Russia. The seller had it identified as "Leptepsia sp." but as I had never heard of that genus I did some digging on Google. What I came up with was a paper written in 1969 by T.N. Alihova. Unfortunately it's mostly written in Russian (cyrillic alphabet) so I can't easily translate it but the names of the genera and species are in the latin alphabet.

The title of the paper is "СТРАТИГРАФИЯ И БРАХИОПОДЫ СРЕДНЕОРДОВИКСКИХ ОТЛОЖЕНИЙ МОСКОВСОЙ СИНЕКЛИЗЫ" which translates roughly (via Google Translate) to "Stratigraphy and Brachiopods of the Ordovician Deposits of the Moscow Syncline".

So, in summary, I believe this is Leptestia sp. from the Aseri stage, Middle Ordovician, Vilpovitsy Quarry, St Petersburg.

Oh, and there is a cystoid on the piece as well that was labelled as "Cyclocrinus sp." which I find suspect as well. A little looking around on the website Fossiilid.info gave me a possible match in Hemicosmites sp.. Update 5/14/15 - Thanks to the comments on this post I now believe this to be Cryptocrinites sp.

Paulicystis sp. Cystoid from Indiana

I recently acquired this Cystoid specimen called Paulicystis densus at a fossil show. It's from the Osgood shale (Silurian, Telychian to Sheinwoodian stage) and was collected in Napoleon, Indiana. I've collected at the same site before but I've only found Holocystites type cystoids. Paulicystis is a new genus that was named in 2011 by T.J. Frest and H.L. Stimple (honoring C.R.C. Paul) based on material donated by Don Bissett. The former two coauthored a paper but it never saw publication until 2011. Sadly both had passed before this occurred. The paper was finally completed in 2011 by C.R.C. Paul and published by the Paleontologial Research Institute in the Bulletins of American Paleontology, Number 380, March 2011. Click on the link to download a copy for yourself.

The opening is the picture below is the oral area

And this is the Anal opening.

These next two pictures show the base of the Cystoid which shows that it had a very wide attachment to the seafloor.

Strobilocystites polleyi Cystoid from Palo, Iowa

Strobilocystites polleyi is the first cystoid that I have from the Devonian. I won it from an auction on E-bay and it fits in well with my collection of fossils from the Cedar Valley Formation of Iowa.

It is composed of many large plates with a single Aulacophore present about 3/4 up the side of the body. Cystoids are odd echinoderms that I don't understand very well so I may have the terminology of the anatomy incorrect.

Side views

This specimen came with a label that states it came from the Cedar Valley Formation (Devonian, Givetian) near Palo, Iowa. I found an old excerpt called "Echinoderms of the Iowa Devonian" by A. O. Thomas that discuss' this species and others found in Iowa. I'm not sure what publication it was part of originally.

Platycystites cystoid from Oklahoma

Platycystites is a strange echinoderm from the Ordovician. It belongs to a class known as Paracrinoids and is thought to have sat upright in the sediments with arms spread out via a thin ridge running across the body. Here is an artists rendering (that I found at the AccessScience website) with Platycrinites on the left.

Next are a couple of specimens from my collection.Note the ridge along the top of the first two pictures. The stem attachment point is on the middle right in the first picture (just below my thumb).

A view of the stem attachment point.

A second specimen that is a little more crushed.

There are several species of Platycystites listed as being known from the Bromide formation. The only good pictures I can find online are here from the Iowa Digital Library. Based on their pics I'm inclined to label these specimens as Platycystites infundus.

The Bromide formation is upper Ordovician in age (Blackriverian [N. American stages] or Sandbian [ICS stages]). The above specimens came from the Mountain Lake Member of the Bromide formation and were found in the 1970's near Davis, Oklahoma.

Caryocrinites ornatus cystoid from the Rochester Shale

I purchased this next specimen from Ebay. It's a Caryocrinites ornatus Cystoid from the Rochester Shale. It is in pretty good shape but could use a little cleaning to bring out some more detail.

This would be the top of the calyx where the arms would have attached.

A slightly different angle of the above view.

The specimen came from the Rochester Shale which is dated to the Sheinwoodian/Homerian stage of the Wenlock epoch of the Silurian.

Here are some specimens from the Yale Peabody Museum of Natural History.


My friend Joe has a very nice intact specimen on his website.

Holocystites from the Waldron shale

Among the fauna found within the Waldron Osgood shale is a Cystoid called Holocystites. Specimens of this odd echinoderm were the most common fossil I found when I had the opportunity to collect the Waldron Osgood shale a few months ago. It could have been the layer or the particular area that was exposed but I was finding them very easily.

They are about the size of a Quail egg or small Chicken egg and that is the general shape that one looks for. Cleaned off you can see a pebble textured surface that is broken into small plates.

Here are several next to each other to show you variety of shape and size.

This is a chunk of the Waldron Osgood shale with a partial Holocystites embedded in it. I say partial because the plate is thin and the fossil does not go all the way through.

This occurrence was not uncommon and some of the loose specimens even displayed this same feature. My theory is that during storm events some Holocystites were buried quickly but some did not get completely covered. Those specimens were exposed partially above the surface and subject to scavenging/erosion. So in essence we are looking at the underside of the bedding plane in the above picture. Since the piece was not found in situ I am only speculating.

The Waldron Osgood shale is Silurian (Telychian to Sheinwoodian stage) in age and is roughly equivalent to the Rochester shale in New York.

*updated 4/24/14*