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St Louis (Fern Glen) Vertebrate?


Eero59

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On a trip to St Louis in 2009, I made a quick stop to do some collecting.

After washing and sieving a bucket of red Fern Glen gravel, among 70 evactinopora, I found these three specimens.

They look somewhat but not exactly like dermal denticles I've seen, I'm not versed in carboniferous verts, so that's just a guess.

The material I think is not silica, mostly smooth and opaque, the small bumps maybe slightly translucent, under magnification the bumps on the smallest one seem to have slight striations. Nothing definitive, but I feel like I'm looking at something organic.

During my upcoming trip to St Louis, I have an afternoon to spend collecting, any suggestions on worthy sites would be greatly appreciated.

Thanks

post-525-0-31881200-1344444609_thumb.jpg

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I have never found any dermal denticles in the Fern Glenn, but they are supposed to be there, particularly in the shale layer at the bottom of the quarry.

What are you interested in finding? There is everything from Coldwater Creek (pleistocene) to Ordovician within driving distance of the city.

Brent Ashcraft

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Xiphactinus

Eero -

Those sure look like denticles. This will sound weird, but try it. (I'm not messing with you!)

See if they stick to your tongue. If they don't, they are probably just parts of evactinoptera with the arms off. If they do, they probably are denticles. (The pores in the bone cause them to stick.)

Rivers are really low now. You should look at hitting the Meramec River near 44/30. The Warsaw Fm. (crinoids, archimedes) is really exposed right now.

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They do stick to my tongue...

On the previous trip I explored the sites along 44 with moderate success; I've walked along the Meramec River once-

I will be taking tools but not not planning on taking large chunks of matrix because I'm flying.

In addition to more Fern Glen samples, I'm particularly interested in blastoids, & have a lead on a site-

Also conulariids... cephalopods, A good Kimmswick Limestone site would be interesting..

Thanks for the ideas- I'll have a limited amount of time so I have to make the most of it.

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Xiphactinus

If you like Fern Glen, there is a big area right off Hwy 55 that has been exposed south of STL. Take the Imperial/Main exit and get on the west outer road. Take it south until it ends. You'll be at a construction area with a ton of Fern Glen exposed.

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I've collected most of the Fern Glen exposures around St Louis

and never have found any dermal denticles.

The 1st specimen ... I agree with Xiphactinus in that it appears

to be a badly weathered Evactinopora. The other 2 appear to

be crinoid.

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Xiphactinus

I've collected most of the Fern Glen exposures around St Louis

and never have found any dermal denticles.

The 1st specimen ... I agree with Xiphactinus in that it appears

to be a badly weathered Evactinopora. The other 2 appear to

be crinoid.

Thanks for weighing in, Indy. For those that don't know, Indy is an expert in this area. I'd go with his ID for sure.

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According to "Geology along I-55" you can find Kimmswick along I-55 at the following locations in the St. Louis area.

Mile marker 182.5 southbound

183.6-183.9

185.6-abandoned quarry in the Kimmswick and the overlying Maquoketa formation can be seen west of the south lane

also bottom layer of roadcut

186.2-Kimmswick, southbound lane

My book is an old version, printed long before they had the interstate marked in .2 mile increments, but I have found it to be fairly accurate still.

Brent Ashcraft

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Thanks Indy Ash Xip and all for the info.

I have collected the FG near Imperial, but never saw the site west of I55, looks like a nice spot thanks.

On the previous trip i stopped @ kimmswick site along I55 southbound, attached is a specimen-post-525-0-01348100-1344626799_thumb.jpg

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