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Echinocaris sp. phyllocarid from the Moscow formation

It is fitting that I end this run of fossils that I've found at the Deep Springs Rd., NY locality with the rarest fossil I've found from the location.

An odd Arthropod that can be found in the Devonian shales of the Moscow formation are Phyllocarids. They were free swimming animals with the tail of a shrimp and the body of a pelecyopd. That is, their bodies were protected by a bivalved carapace with an armored tail that had long spikes at the end. It's more complex than that so let me post the Facebook link below to a 3-d model that an artist created:

There, now you have a good idea what a live specimen should look like. From that we turn to a fossilized specimen that I found which is not quite as visually stunning. It's a positive and negative of the body shell from a species called Echinocaris punctata that is crushed and partially obscured by rock.
A closer view of the positive shows the left valve's pustulose shell surface.
When I turn it 90 degrees some more detail emerges. Note the linear feature about 1/4 of the way up from the bottom margin of the shell. That particular location and shape are what tells me this is an E. punctata. You will also notice some oval shapes just above the linear feature which are also characteristic of this species. Both valves are present with the right valve splayed out above the left. However, some of the positive of the right valve is missing where the rock broke.

Here is the negative of the fossil. I rotated the photo the specimen would be oriented similar to the above positive side.

This is the only specimen I have found of this odd Arthropod family but their fossils are not uncommon in the Windom shale at Deep Springs Rd. Friends of mine have found better specimens at the same locality. It's all dependent on the rock splitting right and you finding the right layer.

This specimen was found at a borrow pit on Deep Springs Road in Madison County, NY which exposes the Windom shale member of the Moscow formation (middle Devonian in age, Givetian stage.)

Stratigraphy.net | Impressum

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