Wednesday, March 25, 2009
Foerstephyllum Colonial Coral
Here is a colonial coral from the Upper Ordovician time period. It was found in eastern Jefferson County, Kentucky. It is probably 14 cm in diameter. It is probably some sort of Foerstephyllum (Bassler, 1941) from the extinct Tabulata coral group.
There is a relatively new book entitled A Sea Without Fish - Life in the Ordovician Sea of the Cincinnati Region by David L. Meyer and Richard Arnold Davis with a chapter by Steven M. Holland. This type of coral is shown pages 76-78. They have a picture of an octagonal tool house built sometime in the early 1900s that is composed of colonial corals from the Richmondian coral beds in Madison, Indiana. The structure can be found in John Paul Park in Madison, Indiana.
They also cite the work of Ruth Browne on these types of coral. Ruth was a Louisville geologist who did some research back in the 1960s and 1970s in this area.
I think that the easiest way to differentiate Foerstephyllum from Favostella is that in Favostella the septa nearly reach to center of the corallite. In Foerstephyllum, the septa is relatively short; just little ridges off the wall of the corallite.
ReplyDeleteNice specimen, did you dip in acid to clean it up some? I found some of these two years ago while swinging through the area and wondered what species they were. Being that I mostly see Devonian near me I was thinking Favosites.
ReplyDeleteFound your site through the Fossil Forum. Greetings from Shamalama!
What happens when you cannot find any septa?
ReplyDeleteI have only found 4 so far that have visible intact septa (see http://louisvillefossils.blogspot.com/2008/12/cyathophylloides-cf-c-burksae.html#links from December 2008 - click on picture to make larger).
I would like to learn how to thin section which from the papers I have read is the method for seeing septa and other details of the fossil specimen.
Thanks for the information.
Thanks for the comment Dave.
ReplyDeleteThe colonial corals I post have been cleaned by lots of running water. There is some packed mud still in some of the corallites. I tried some hydrochloric acid (bought at Home Depot) to clean this out on another specimen but it just started to melt the fossil and did nothing to the dirt. I might have to use a dental pick and Dremel tool etching bit to clear it out with. I used this method on Halysites with good results.
If you have access to the JSTOR system (found at university libraries) look up some of the papers for Ruth Browne. She did some great research in the Louisville area on this type of coral.