Carneyella ulrichi Bassler & Shideler, 1936 fossil edrioasteroid (~2.2 cm across) encrusting a limestone hardground from the Ordovician of Kentucky, USA.

Here's a nice Carneyella ulrichi edrioasteroid from the Cincinnatian outcrop belt of northern Kentucky, USA. It is encrusting a fossiliferous limestone hardground. Hardgrounds are synsedimentarily cemented portions of the seafloor, usually involving carbonate sediments. Sessile, benthic organisms have to cement themselves onto, or bore into, hardground surfaces.

This Carneyella ulrichi-bearing hardground horizon was discovered in spring 1998. The encrusting biota includes trepostome and cyclostome bryozoans, crinoid holdfasts, cornulitid worm tubes, and the edrioasteroids Streptaster vorticellatus, Carneyella pilea, Carneyella ulrichi, and Curvitriordo stecki. Trypanites borings are also present on the hardground. The edrioasteroid fauna has generated much excitement, resulting in quarrying of the horizon and intense collecting by professionals and collectors.

This Carneyella ulrichi is a rare edrioasteroid species that is known only in the Maysvillian Stage (middle Upper Ordovician) of the Cincinnatian outcrop area of northern Kentucky. Before spring 1998, the only known specimen on Earth was the holotype (USNM S-3964, housed at the U.S. National Museum of Natural History, Smithsonian Institution, Washington D.C., USA). Carneyella ulrichi was first named & described by Ray Bassler and William Shideler in 1936 using the USNM S-3964 specimen, a partially disrupted skeleton encrusting a Hebertella occidentalis brachiopod shell. The most distinctive feature of Carneyella ulrichi is the presence of numerous pointed tubercles covering the plates of the skeleton.

This particular specimen, found in spring 1998, is the 2nd known example of the entire species. It led to the discovery of a relative abundance of new material. The new material all comes from a large roadcut through Jersey Ridge along Rt. 62/68 (formerly Rt. 3071), just south of Harsha Bridge over the Ohio River, ~1 mile east of Moranburg, ~2 miles northwest of Maysville, northern Mason County, northeastern Kentucky, USA. There are actually two large roadcuts in this area: 1) a larger, lower cut immediately north of the bridge over Lawrence Creek; and 2) a smaller, upper cut immediately south of the Lawrence Creek bridge. Carneyella ulrichi has been found at both the upper & lower cuts.

This discovery specimen was found by Christian Steck in spring 1998, then a structural geology graduate student at Ohio State University (Columbus, Ohio, USA). The specimen was first identified as Carneyella ulrichi by James St. John, then a paleontology graduate student at Ohio State. The species identification was verified by Colin Sumrall, an edrioasteroid researcher at the Cincinnati Museum Center (now at the University of Tennessee), who has since published on the fossils from this hardground horizon (see reference list below).

Classification of Carneyella: Animalia, Echinodermata, Echinozoa, Edrioasteroidea, Carneyellidae

Stratigraphy: ~mid-Bellevue Formation (part of the "Grant Lake Formation"), middle Maysvillian Stage, middle Cincinnatian Series, middle Upper Ordovician

Locality: Jersey Ridge outcrop (Harsha Bridge South outcrop; Maysville West outcrop) - southern end of eastern side of Rt. 62/Rt. 68 roadcut through Jersey Ridge, just south of the Harsha Bridge over the Ohio River, northern Kentucky, USA (38° 40’ 27.27" North, 83° 47' 53.11" West).

Edrioasteroids are an extinct group of sessile, benthic, filter-feeding echinoderms - they’re related to starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers. They are attractive and much-sought-after fossils among collectors and professional paleontologists. Edrioasteroids have circular to subcircular, blister-like skeletons (originally inflated during life) with five, frequently curved, ambulacral structures that held tube feet used in feeding. The skeleton consists of small calcitic plates that frequently overlap, especially along the border areas. They were obligate encrusters and attached themselves to inorganic or biologic hard substrates (frequently hardgrounds or brachiopods). Edrioasteroids are known from the Cambrian to the Pennsylvanian.

Some literature on Carneyella ulrichi & this hardground horizon:

Bassler, R.S. 1936. New species of American Edrioasteroidea. Smithsonian Miscellaneous Collections 95(6).33 pp. 7 pls.

Bell, B.M. 1976. A study of North American Edrioasteroidea. New York State Museum and Science Service Memoir 21. 447 pp.

Sumrall, C.D., C.E. Brett, P.T. Work & D.L. Meyer. 1999. Taphonomy and paleoecology of an edrioasteroid encrusted hardground in the lower Bellevue Formation at Maysville, Kentucky. pp. 123-131 in Sequence, cycle & event stratigraphy of Upper Ordovician & Silurian strata of the Cincinnati Arch region. 1999 Field Conference of the Great Lakes Section, SEPM-SSG (Society for Sedimentary Geology) Field Trip Guidebook. [reprinted 2001 in Kentucky Geological Survey, Series XII, Guidebook 1: 123-131.]

Berg, M.V. 2000. Paleoecology and paleoenvironment of an Upper Ordovician hardground (Grant Lake Formation, Cincinnatian Series, northern Kentucky). pp. 240-243 in Thirteenth Keck Research Symposium in Geology, Proceedings, Whitman College, Walla Walla, Washington, April 2000.