Found In Southeastern Kentucky Creek

[Special teacher]

I am a school teacher, and received what I think may be some sort of fossil from a relative recently. I would love to share this with my class, but cannot seem to find anything similar online in order to identify it. The only information I have is that it was found in a creek in southeastern Kentucky, USA. I would like to be able to tell my students what this is when I share it with them...any ideas? I previously asked for help in identifying it from a natural history museum, but they were stumped, as well. They suggested I post it here for help. Thanks so much!

[ashcraft]

Upside down coral?

fkaa

[Bullsnake]

It looks to me like an ichnofossil, or trace fossil like a resting burrow (except upside-down).

[vertman]

I am in agreement with Bullsnake.

[Harry Pristis]

Ichnofossil, a domichnia, is probably the best guess . . . a resting burrow, as Bullsnake suggests.

[BobWill]

Welcome to the forum. I was given a similar fossil said to be from northern Oklahoma that was identified as a resting burrow as the others said. Of course it would have been situated in a position inverted from your photo.

[trilobiteruss]

These trace fossils are placed in the Ichnogenus Conostichus

We found many over the years in Pennsylvanian rocks in Illinois.

My colleague Joe Devera and I believe (as some do but others think otherwise) that they are the trace fossil an animal similar to a sea anemone. In your specimen I see some of the ribbing pattern, typical, and on the bottom, not normally seen, is a 12 lobed pattern. Typically they are found in sediments such as interbedded shale/mud and very thin very fine grained sand lenses.

There was a good discussion of this by Indy (Barry) and others on the forum back in 2011 also:

http://www.thefossilforum.com/index.php/topic/22986-odd-texas-pennsylvanian-fossils/

Other links to this fossil include:

http://viewsofthemahantango.blogspot.com/2012/03/conostichus-trace-fossils.html

http://igs.indiana.edu/FossilsAndTime/conostichus.cfm

http://www.jstor.org/discover/10.2307/1302785?uid=2129&uid=2&uid=70&uid=4&sid=21104531066213

http://strata.uga.edu/cincy/fauna/tracefossils/Conostichus.html

conostichus fossils

This abstract to a journal (I do not have access to) assigns them to sea anemone

http://www.nrcresearchpress.com/doi/abs/10.1139/e88-085#.U9XIksI7ERk

The ichnotaxonomy of Conostichusand other plug-shaped ichnofossils

S. George Pemberton, Robert W. Frey, Richard G. Bromley

Canadian Journal of Earth Sciences, 1988, 25(6): 866-892, 10.1139/e88-085

ABSTRACT

The systematics of the single-entrance, plug-shaped, soft-substrate trace fossils have long been in need of revision. At least 15 ichnogenera, comprising 32 ichnospecies, have been used, but an examination of the type material that is available suggests that this is excessive. A review of ichnotaxa indicates that the valid ichnospecies can be encompassed within five ichnogenera as follows: Conostichus (five ichnospecies), Bergaueria (including Kulindrichnus, three), Conichnus(including Amphorichnus, two), Dolopichnus (one), and Astropolichnus (one). In addition, several minor ichnogenera for related structures are considered. These are Calycraterion, Margaritichnus, and Mammillichnis.The majority of plug-shaped structures are interpreted as cubichnia or domichnia, dominantly of actinarian sea anemones. The occurrence of these trace fossils is predominantly in Paleozoic rocks.

Edited July 28, 2014 by trilobiteruss

[Special teacher]

Thanks so much for the information! I am happy to have an idea of what it may be, and look forward to sharing this information with my students. I appreciate your assistance.