Friday, June 29, 2012

Insect fossils from the Florissant formation

Insects are somewhat commonly preserved in the shale layers of the Florissant formation. Below are some fine examples that I found over twenty years ago.

A Robber fly (?)



Some kind of wasp or flying ant (both sides)




A moth with some wing patterning preserved




The Florissant formation is the remains of a temporary lake that is dated to the Eocene period (Priabonian stage) and is located in Colorado.

Wednesday, June 27, 2012

More plant fossils from the Florissant formation

Here are some more plant fossils from the Florissant formation that I found 20 years ago.

This is only a partial leaf but it reminds me of an alder tree

Pine needle

Some sort of evergreen foliage I think.

Fossil reeds


Both halves of a partial oak leaf



The Florissant formation is the remains of a temporary lake that is dated to the Eocene period (Priabonian stage) and is located in Colorado.

If you want a good book with pictures of some spectacular fossils that have been found in the Florissant formation, check this book out: Fossils of Florissant, by Herbert W Meyer.

Monday, June 25, 2012

Plant fossils from the Florissant formation

A number of years ago I had the opportunity to collect the Florissant formation at a pay quarry outside of Florissant National Monument. I found a number of interesting fossils which I will show here and in upcoming posts. Today I have some plant material in the form of various leaves.

Juniper?

These next couple look like Willow (?) leaves


Some Metasequoia


I'm not sure what this is, a fern of some sort?

The Florissant formation is a layer of paper shale that was lain down in a temporary lake in a volcanic region. The nearby volcanoes would erupt periodically and belch out ash and occasional lahars. These eruptions would kill local wildlife and sweep plant debris into the lake and then bury them. The thin layers of ash preserved organic remains very well and so some spectacular fossils can be found including birds with feathers, butterflies with the wing coloration preserved and many species of plants all of which paint a picture of the environment around the lake at a point in the late Eocene period (Priabonian stage).

 Here is a link to the website of the Quarry where I collected over 20 years ago. Nice to see that they are still in business and are responsibly managing this resource so anyone can have the thrill of finding something special.

A good resource to read if you want to learn more about the Paleoecology and Paleoenvironment of the Florissant formation look for this book: Paleontology of the Upper Eocene Florissant Formation, Colorado, By Herbert William Meyer, Dena M. Smith

Saturday, June 23, 2012

Odds and ends from Arkona

Today I have some random pictures of fossils from Arkona that I found in a folder on my desktop. Most are one or two pictures of oddball fossils or interesting growth features.

The bryozoan Taeniopora from the Hungry Hollow member of the Widder formation

Styliolina from the Arkona formation

A Devonochonetes sp. shell with an unknown bryozoan or worm tube on the pedicle valve....

And worm tubes on the brachial valve.

All specimens were found along the Ausable river and Hungry Hollow near Arkona, Ontatio, Canada. The Hungry Hollow member and Arkona formation are both Middle Devonian in age (Givetian stage).

Thursday, June 21, 2012

Tornoceras arkonense from Arkona

I'm a little surprised that I hadn't posted a specimen of Tornoceras arkonense to my blog yet. It's a small cephalopod that is found only in the Arkona formation at the site where I collect at Hungry Hollow along the Ausable river in Ontario, Canada. The fossils are preserved by pyrite and can be very detailed. below is a typical specimen with views of the suture in profile and from the front.



The Arkona formation is middle Devonian (Givetian stage) in age.

Wednesday, June 20, 2012

Cyclolites ellipticus from france

Cyclolites ellipticus is a fossil solitary coral from the upper Cretaceous (Campanian). This specimen came from near Blanzac, France and was sent to me by my friend, Gery. Only the upper surface where the polyp was attached is shown in this specimen.




Here is a picture of a complete specimen.

Compare this specimen to Microcyclus thedfordensis which was also a solitary coral but it was a member of the Rugose coral which became extinct by the end of the Permian.

Tuesday, June 19, 2012

Pycnodonte newberryi from Utah

While visiting the Capitol Reef National Park I stopped off at a site outside of the park to collect some prolific oyster fossils. They are Pycnodonte newberryi and come from the Mancos shale. the shells are generally small but when found they cover large areas. They are considered rudists by some and this is a good example of how they could form reef like structures. Here is a typical specimen with both valves.

Left valve top

Left valve anterior

Left valve left side

Left valve posterior

Left valve right side

Left valve interior

Right valve

Right valve profile (life position?)

The Mancos shale is Cretaceous in age and is dated to the late Cenomarian stage. The site these were found at is outside of the park boundaries on federal BLM land.

Sunday, June 17, 2012

Camarotoechia (?) from the Keyser formation

Camarotoechia is a small brachiopod that is fairly common in the Paleozoic. At times it seems to be another "dumping ground" for similar looking shells like Spirifer is. I believe that the fossil shown below is Camarotoechia and was found in the Keyser formation in Pennsylvania.

Pedicle valve

Anteiror

Brachial valve

Posterior

Profile

I've posted pictures of Camarotoechia from other localities like Arkona, Oklahoma and New York.

The Keyser formation is Silurian to Devonian in age (Pridoli to Lockhovian stage).

Friday, June 15, 2012

Howellella (?) from the Keyser formation

This fossil is from the Keyser formation but I'm not entirely sure of it's name. I think it's a Howellella but it could also be Megakozlowskiella, Delthyris or some other Spirifer. All are known from the Keyser so ID is difficult.

Brachial valve

Anterior

Pedicle valve

Posterior

Profile

The Keyser formation is Silurian to Devonian in age (Pridoli to Lockhovian stage).

Wednesday, June 13, 2012

Taeniopora exigua from the Mahantango formation

On a visit this past winter to a borrow pit that is working the Mahantango formation I came across a layer or lens of a delicate bryozoan. It's called Taeniopora exigua and generally it's found as small, broken pieces. At this location though there must have been a forest of these animals since they are preserved in such profusion and completeness.

Here is a large piece of mudstone which is riddled with the casts and molds of  Taeniopora exigua

A couple of typical examples. Note that they are naturally flat shaped like a leaf and not round or stick like. The growth pattern is similar to another species called Sulcoretepora. The distinguishing feature between them is that Taeniopora has a central ridge that runs up the middle of most branches. You can see it in the specimen shown below.
More pieces and examples are below.







I've found Taeniopora pieces before from other locations but never from the Mahantango and never in such profusion. There must have been perfect conditions for a small forest of these bryozoans to all congregate in an area. I haven't found any other bryozoans in the same general area where I found these and the rest of the pit yields fossils only sparingly and typically not in great concentrations. All the specimens shown came from the Mahantango formation which is Givetian in age. Another item of note is that the rock these fossils were found it is a very weak mudstone that has been extensively leached. The yellow color is telling, as the rocks are normally dark grey to brown, and so is the softness of them. When I found them it had been raining and the rock was very soft, almost enough so that I could pull it apart with my hands.