Long Thingy Unknown

[Bev]

Ordovician

Either Maquoketa or Decorah Shale

SE Minnesota

I thought it was a ceph... Then there are these real consistent marks on the side... And then turning the rock over it actually seems to be fossilized through the rock...

Don't know what to make of this critter. Anybody know what it is?

For Scale

Closeup

Where it comes through the back. At least that is what it seems to me.

Thanks for looking!

[Carl]

Hi Bev! Don't know what you have here but it does look like it's preserved as beekite. This would explain the marking which would not have been present in the living organism.

[Bev]

Thanks Carl!

Found this 6 page pdf on beekite: http://australianmuseum.net.au/Uploads/Journals/16668/1197_complete.pdf

Quite an interesting read, even though I didn't understand a lot of it.

But no one has an idea of what the critter might be?

I'm between a ceph and a crinoid as it has distinct lines on it that I can see and feel.

[howard_l]

A lot of the time when a fossil is silicified it loses all or most of the original fossil detail but retains the general shape. This could have been a fossil or a trace fossil like a burrow. The best way to id it might be to look around where you found it for similar shaped object in hopes they were not silicified and have fossil detail. If all you find is similar silicified material in various shapes I would go with trace fossil.

[Bev]

A lot of the time when a fossil is silicified it loses all or most of the original fossil detail but retains the general shape. This could have been a fossil or a trace fossil like a burrow. The best way to id it might be to look around where you found it for similar shaped object in hopes they were not silicified and have fossil detail. If all you find is similar silicified material in various shapes I would go with trace fossil.

Thanks Howard for explaining that beekile makes fossils impossible to ID.

[Tethys]

It's an oddball. The only thing that looks familiar is the small pyrite ostracod on the back side. I can't make out any details of whatever is embedded in the same side as the ostracod, but it looks like it is a white, mostly hollow, and very thin walled tube. The reddish tube in the first photo looks somewhat like the drawings of Raufella fucoidae by Sardeson. (there is also a R. filosa in old books) It was thought to be an algae, then it was decided it was a sponge and its name was changed to Dictyspongia. Then a sponge authority named Rauff said that the fucoid form and the filosa form were not an organism at all. I cannot find any reference to what it was decided that they are, but I think they are currently considered worm tubes and trace fossils. You will find lots of references to the "Fucoid" bed in old literature. It is at the top of the

Decorah Shale, above the "Stictoporella" bed which is the layer that is full of bryozoans.

Edited July 28, 2014 by Tethys

[Bev]

Thank you Tethys for taking a look at it!

[kurdelmb]

It's an oddity Bev... You and I often hunt the same general strata and I have never encountered anything like this. Curious... ???

[Gen. et sp. indet.]

Compare with septemchitonids, maybe.