Placoderm Armor?

[squalicorax]

Hey all. My dad found this along the Milwaukee River, not even looking, and gave it to me to figure out what it is.

This is Middle Devonian Marine dolomite. I have collected at various other river cuts less than a mile up. Never seen anything like this. The texture is killing me. It looks like it weathered away, with only some of it left exposed, and a cast left.

thanks for looking.

[pleecan]

Quite possible... I am leaning towards a yes.....

For comparison...

This is protitanichthys placoderm armor from Arkona,Mid Devonian.

[RCFossils]

I would agree with Peter. Looks like placoderm material.

Great find!

[Missourian]

I think it could be a piece of an eurypterid.

Segment detail for comparison:

Edited September 24, 2012 by Missourian

[Auspex]

I think it could be a piece of an eurypterid.

This example is a better match for the 'chevron' pattern of the mystery specimen.

[pleecan]

The first photo upper apex suggest bone texture rather than eurypterid chitin ... still think it is placoderm armor of some sort.... not protitanichthys.

Suspect if you lift the bone there will be ornamentation raised bumps on the bone structure. The bone should be resistant to acetic acid.....

[Malcolmt]

Does not look like eurypterid chitin to me