Indiana Richmondian Road Cut

[ScarpedCliff]

To get out of the house while sick, my wife and I recently took a rainy road trip to a large road cut in southeast Indiana. I posted last week about finding my first complete Isotelus there. Here are a few more fossils we found there during the last trip (and perhaps some from the previous one). Most of these are from the Liberty Formation, but some could be from higher or lower in the Richmondian stage.

First, here's a large shot giving examples of the common fossils we found. I photo-edited labels in as accurately as I could, but it's possible I have some of these misidentified. In particular, the Vinlandostrophia cypha might be a V. clarksvillensis instead, and the small Hiscobeccus could be something else (but I'm reasonably sure it is not Zygospira). The right one of the two monoplacophorans might be Sinuites sp. (although it is hard to see details from the angle I photographed it from). If anyone sees errors or can ID fossils I haven't, I can always edit the image.

[ScarpedCliff]

Here are some of the comparatively common Flexicalymene retrorsa minuens we found. The largest of these is only about a centimeter long.

Edited February 11, 2016 by ScarpedCliff

[ScarpedCliff]

Here's a nice Flexicalymene my wife found. It is the interior of the thorax, and I think the living trilobite would have been at least five centimeters long.

Edited February 11, 2016 by ScarpedCliff

[ScarpedCliff]

This is Foerstephyllum vaccum, one of the rarer tabulate corals in the area. It's only the second specimen I've seen, while the encrusting Protarea richmondensis is much more common.

[PaleoWilliam]

Nice finds!

[Pumpkinhead]

Awesome fossils

[Peat Burns]

Very nice assemblage of fossils.

[fossilized6s]

Very nice finds. I hope to hit that road cut sooner than later.

[Ludwigia]

Nice to see someone else exploiting road cuts as well as me Very nice finds and a productive site by the looks of things!

[erose]

Your tabulate coral is a very nice specimen. Plenty of detail to get a better identification. I would assume that came from the upper part of the cut which gets into the Whitewater/Saluda formations.

I think your IDs are pretty good. The large gastropod without shell may not be Cyclonema. I've never known them without shell and there are quite a few gastropods to sort thru in the Cincinnatian. I can not recall the name off hand but you may want to pick up a copy of Fossils of Ohio from the state geo survey. Combined with the book that the Cincinnati Museum of Natural History puts out you can cover the majority of possibilities.

I grew up in that area and the Cincinnatian Series is what fossil collector dreams are made out of. I spent a number of years compiling a list of almost every species listed for the Cinci and it came to around 1,500. After sorting out the various synonyms and other "duplications" it still was between 750-900 and closer to the later. Bryozoans alone were in the hundreds.

Edited February 11, 2016 by erose

[Peat Burns]

The snail steinkern could be Clathrospira.

[Ridgehiker]

Thanks for sharing your finds. Your original photo with the superimposed information is a great way to present them.

Re tabulate corals. It can be hard to give a definite label. Usually identified because they are found in a particular member of a formation and 'look the same' and thus assumed to be the same. Werarely use them in biostratgraphic studies because they lack sufficient features to note any subtle changes over time. Rugosa corals and brachs are more diagnostic. A thin section of a rugose coral shows a lot of detail changes in the septa. In contrast a tabulate tends to be more or less the same over longer periods of time.

Re erose and his comments on bryozoans. I've wondered why this time period yields such a rich variety of bryozoans. Perhaps there was something in the chemistry of the oceans.

[ScarpedCliff]

The snail steinkern could be Clathrospira.

Thanks. I just pulled it out to have a look, and you're right, it is very similar to Clathospira subconica (which can be found in the Lower Whitewater). My knowledge of gastropods is very limited, though, so I doubt I know enough to be certain.

[ScarpedCliff]

Your tabulate coral is a very nice specimen. Plenty of detail to get a better identification. I would assume that came from the upper part of the cut which gets into the Whitewater/Saluda formations.

I think your IDs are pretty good. The large gastropod without shell may not be Cyclonema. I've never known them without shell and there are quite a few gastropods to sort thru in the Cincinnatian. I can not recall the name off hand but you may want to pick up a copy of Fossils of Ohio from the state geo survey. Combined with the book that the Cincinnati Museum of Natural History puts out you can cover the majority of possibilities.

I grew up in that area and the Cincinnatian Series is what fossil collector dreams are made out of. I spent a number of years compiling a list of almost every species listed for the Cinci and it came to around 1,500. After sorting out the various synonyms and other "duplications" it still was between 750-900 and closer to the later. Bryozoans alone were in the hundreds.

I think my wife found the coral on our first trip, and she doesn't recall where it came from. We mostly collected in the Liberty layers, but things do wash down from above. Do you think it is Foerstephyllum vaccum (that's the only species I'm familiar with that looks anything like this from the Cincinnatian series)?

You have a good point about the large gastropod. Cyclonema seem to be about the only ones I ever find with a shell (Oddly, I've found a couple Monoplacophorans with preserved shells...has it been anyone else's experience that they preserve well?). I have the book from the Cincinnati museum, but I appreciate the recommendation for Fossils of Ohio.

You wouldn't happen to have that list still saved somewhere, would you? Sounds interesting.

As far as the area, I know I should be grateful to live here, and it is nice to have the chance to go fossil hunting several times a week. But, I do sometimes get a little bored (at least until I find the next fossil I've never seen before, which is easy here... ). I have a strong preference for Mesozoic and vertebrate fossils, and I miss those. But, I always have vacations down south and out west to get my vert paleo "fix."

[erose]

You may be familiar with this web site: http://strata.uga.edu/cincy/index.html

The photo and description of Foerstephyllum is a pretty good match. Corals like that are known to occur in the top layers of that road cut.

Different molluscs had different forms of calcitic shells. Some preserved and some didn't. This goes for both bivalves and gastropods. Cyclonema and few others preserve, while Clathrospira doesn't.

PM me and I'll email you my list. It is a work in progress and I haven't spent much time with it since about 2013. There are probably plenty of revisions and additions yet to be tackled based on more recent research and taxonomic revision.

[Peat Burns]

Thanks. I just pulled it out to have a look, and you're right, it is very similar to Clathospira subconica (which can be found in the Lower Whitewater). My knowledge of gastropods is very limited, though, so I doubt I know enough to be certain.

Steinkernen are usually very difficult to identify with certainty. The Cyclonema, as mentioned usually have a persistent shell. Lophospira often do as well. I have not yet found a Clathrospira with a shell (usually just a steinkern, but I do have some covered in Protarea richmondensis (coral)). Loxoplocus (Paupospira) bowdeni is another one for which I've only found steinkernen. I love finding gastropods in any state of preservation, though!

[ScarpedCliff]

Steinkernen are usually very difficult to identify with certainty. The Cyclonema, as mentioned usually have a persistent shell. Lophospira often do as well. I have not yet found a Clathrospira with a shell (usually just a steinkern, but I do have some covered in Protarea richmondensis (coral)). Loxoplocus (Paupospira) bowdeni is another one for which I've only found steinkernen. I love finding gastropods in any state of preservation, though!

Thanks. I've seen the same thing: a gastropod (I don't recall the genus) preserved by an encrustation of Protarea richmondensis. I wonder how many comparable situations there are like that in paleontology, where preservation is enhanced by other species.

[Peat Burns]

Thanks. I've seen the same thing: a gastropod (I don't recall the genus) preserved by an encrustation of Protarea richmondensis. I wonder how many comparable situations there are like that in paleontology, where preservation is enhanced by other species.

One interesting example, although a bit more indirect, is the hypothesis that the presence of snails and clams in deposits bearing dinosaur eggs helps preserve the dinosaur eggs because the snail shells buffer the acid soils that normally dissolve the egg shell!

Ref:New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium

by Michael J. Ryan

Edited February 15, 2016 by Peat Burns