Friday, October 9, 2009

Indiana Button Coral Fossil

The Hadrophyllum orbignyi (Edwards & Haime, 1851) is found in the Speeds Limestone found in Clark County, Indiana. These two fossils are about the size of an American nickel. I sometimes wonder what this little Devonian Period creature looked like when alive. Looking at this fossil sometimes makes me hungry. It reminds me of my grandmother's peanut butter cookies that had this color and texture with a criss-cross pattern pressed into them.
While doing research on a brachiopod fossil from a recent post I came across some really nice websites:
This French website on brachiopods is very well done.
The University of Iowa has some really good brachiopod images. One project they did called "Fossils In My Backyard" is great. it shows the geological map of the state of Iowa and then one can click on a county and see the fossils found there. I did not realize they had so many time periods exposed in their state.
The Alberta Palaeontological Society website is well organized. I was impressed with quality of their sample bulletin and the extensive member's guide. They even published a book on vertebrate fossils entitled, "Guide to Common Vertebrate Fossils from the Cretaceous of Alberta".


  1. I imagine these looked like modern mushroom corals or possibly anemones (sp?). You've always found them as singles, never attached to anything, right? I'd say it was partially mobile like anemones.

  2. Thanks for the comment.

    Yes, they are found as solitary fossils. They are usually mixed in with Athryis brachiopods and Eridotrypa bryozoans.

    I will look up images of mushroom corals.

  3. For the modern "mushroom corals" go to Google images and enter "Fungia coral", "Micrabacia" and also "Microcyclus", which is a Devonian button coral.