Iowa Devonian Fossil (Fish Armor?)

[BenWorrell]

Help please!

 

Last weekend I was on a club trip here in Eastern Iowa, and I found a really cool fossil. According to other club members, the layer it appeared to come from is roughly 385 million years old, possibly from the Little Cedar Formation, although we can't be sure. We believe that it is likely plating from an armored fish. A photo with a couple measurements is attached. The bumps vary in size, but are about 3 mm in diameter.

I've reached my photo size limit, so I will try to add more close up photos in a little bit. 

 

What species could this be? 

What part of the body would it be from?

 

Thanks!

-Ben Worrell

 

 

[Al Dente]

I think you are right. It looks like a bony plate from a large placoderm. 

[FossilDAWG]

I agree, it's a placoderm plate.  Nice find!

 

Don

[BenWorrell]

Here are some close ups....

[BenWorrell]

11 minutes ago, Al Dente said:

I think you are right. It looks like a bony plate from a large placoderm. 

Is it possible to tell if it is one of the bottom dwelling ones or a predator type?

[Fossildude19]

Great find!   

Still hoping to find my own someday. 

Cheers!

[Jeffrey P]

Congratulations on a placoderm plate. excellent find. Thanks for sharing it.

[hemipristis]

Very nice!  Concur, placoderm.

A quick google search wasn't that helpful except for one image, with the similar ornamentation, Plourdosteus canadensis:

 

[minnbuckeye]

Hey Ben,

Great find!!! I was at the same quarry and heard about your find. Everyone said if I wanted to see the placoderm, look for the guy with the green hat and green vest. Unfortunately our paths never crossed or you changed hardhats and I didn't know that!!!! What level was the placoderm found on? The reason I ask is that I found a placoderm tooth that very same day. So I am curious if we were on the same level. I was up on the highest level clear back at the south end. Here is the tooth:

 

  

 

Mike

[BenWorrell]

4 hours ago, hemipristis said:

Very nice!  Concur, placoderm.

A quick google search wasn't that helpful except for one image, with the similar ornamentation, Plourdosteus canadensis:

 

Thanks for the suggestion!!!

[BenWorrell]

22 minutes ago, minnbuckeye said:

Hey Ben,

Great find!!! I was at the same quarry and heard about your find. Everyone said if I wanted to see the placoderm, look for the guy with the green hat and green vest. Unfortunately our paths never crossed or you changed hardhats and I didn't know that!!!! What level was the placoderm found on? The reason I ask is that I found a placoderm tooth that very same day. So I am curious if we were on the same level. I was up on the highest level clear back at the south end. Here is the tooth:

 

  

 

Mike

Mike, I was on the lowest level. I also found a tooth similar to that in a separate location, although it's not prepped and it might just be a piece. Maybe I'll post some pics tomorrow. 

[BenWorrell]

21 hours ago, minnbuckeye said:

Hey Ben,

Great find!!! I was at the same quarry and heard about your find. Everyone said if I wanted to see the placoderm, look for the guy with the green hat and green vest. Unfortunately our paths never crossed or you changed hardhats and I didn't know that!!!! What level was the placoderm found on? The reason I ask is that I found a placoderm tooth that very same day. So I am curious if we were on the same level. I was up on the highest level clear back at the south end. Here is the tooth:

 

  

 

Mike

Mike,

 

Here are some photos of the crushing plate I found unprepped.

[minnbuckeye]

Nice! Maybe in 30 years we can piece together a complete placoderm from our partials!!