Thursday, November 27, 2014

Leptestia sp. brachiopod & Hemicosmites 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 gave me a possible match in Hemicosmites sp.

Tuesday, November 25, 2014

Sulcoretepora cf. S. incisurata bryozoan from the Mahantango formation

Sulcoretepora is a flat, branching bryozoan that is somewhat common in the Devonian. The specimen below comes from the Mahantango formation of central Pennsylvania, likely from Seven Stars or Deer Lake. I bought it at a fossil show due to the length of the fossil since, normally, I only find small sections of the skeleton that were broken off from the main colony by storms or otherwise redeposited. This specimen also has several smaller branches forking off from the main portion.

Based on the book "Stratigraphy and Paleontology of the Mahantango Formation in South-central Pennsylvania" by Robert L Ellison, Bulletin G48, Pennsylvania Geological Survey, 1965, I am calling this specimen Sulcoretepora cf. S. incisurata. Note, the use of cf. in this name indicates that the species is not known but is similar to specimens of Sulcoretepora incisurata known from other locations. It's short hand for the Latin word "confer" meaning "look at other sources".

I've blogged about some nice examples of Sulcoretepora deissi I found in the Silica Shale here. Sulcoretepora has a similar growth habit as Taeniopora exigua like in the specimens I blogged about here.

Sunday, November 23, 2014

Mioplosus labracoides fish head from the Green River Formation

I purchased this fish fossil from a collector just because of it's size and preservation. The collector didn't know what the genus of fish it was but I did a little digging and I think it's a Mioplosus labracoides. The fossil was collected from the Green River formation near Kemmerer, Wyoming (Paleogene, Eocene epoch, Ypresian stage). I have not yet found any Mioplosus fossils myself so this filled a hole in the collection as well as being a cool looking fossil.

Friday, November 21, 2014

Asaphellus fazovataensis trilobite from Morocco

A recent addition to my Moroccan trilobites is this Asaphellus fezouataensis from the Ordovician (Floian stage), Fezouata Formation in the Draa Valley near Zagora, Morocco (Western Sahara). I bought this at a fossil show and it was fairly inexpensive. I see some now on E-bay that are priced much higher so either I got a good deal, I found it early enough on the market or (more likely) the sellers are trying to get as much as they can for it.

The fossil looks very similar to Isotelus species that are found here in North America within late Orodvician rocks.

Wednesday, November 19, 2014

Furcaster palaeozoicus starfish from the Hunsruck slate near Bundenbach, Germany

In the last post I showed you some pictures of fossils from the Hunsruck Slate (Emsian stage of the Devonian) in Bundenbach, Germany that were on display at a rock, fossil and mineral show. Today I'm going to show you the piece of the Hunsruck that graces my collection. At the same show that I saw the display of fossils from Bundenbach, I also came across this piece of slate with two Fucaster palaeozoicus starfish showing some current orientation.

The plate is 22cm along the longest edge and 17 cm along the shorter edge. They are both ventral views with some nice detail.

This specimen is 12cm long by 5.5cm wide

The "halo" that surrounds the central star shape and arm bases is the soft body of the animal. Unlike the arms, the body didn't have any special armor to protect it.

The second specimen is shorter at 7cm long, since part of one arm extends off the plate, and 4cm wide.
I also love the little string of white quartz that cuts across the right specimen. It lends some authenticity to the piece and adds some interest. The obvious star shape in the middle of the body is the result of the muscles that controlled the mouth relaxing after the animal died. Normally they would be closed and the bottom of the animal would look more armored.