Tuesday, January 21, 2014

Stereolasma rectum coral from western New York

Possibly the most common and easily recognized coral found in the middle Devonian rocks of western New York is Stereolasma rectum. This is a small, solitary horn coral identified by the typical "horn" shape with obvious septal grooves on the side of the corallite. It thrived in the limy mud that was prevalent at the time but didn't seem to grow very high above the sediment surface of the sea floor. The specimens below were collected from along Lake Erie and are from either the Wanakah Shale mbr. of the Ludlowville Fm. or the Windom Shale mbr. of the Moscow formation.

Specimen #1

Specimen #2

Often the calices of these corals are infilled with rock or crushed as on this specimen.

Specimen #3, Occasionally you will find a specimen where the thecal cup has been broken away and the septae are visible as in the below fossil. (This particular specimen was collected from the Ledyard shale mbr. of the Ludlowville Fm. near East Bethany, NY)

No comments:

Post a Comment