Nebraska Invertebrate Fossils - Cnidarians, Lophophylloid Corals from the Ervine Creek Limestone
These corals are usually small (less than 50 mm long) that have a single spiny columella that is located in the center of the calyx where the septa (verticle partitions) join together. See broken away section of calyx in the small corallite in the center image. Lophophyllidium proliferum (McChesney) is commonly found in offshore shale deposits in the mid-continent. Invertebrate faunas in offshore shale facies are often composed of smaller, thin-shelled, unornamented animals as opposed to large, thick-shelled, ornamented animals that are commonly found in regressive limestone deposits. The offshore shale deposits are usually deposited in deep, cold water whereas the regressive limestone deposits are laid down in warm, shallow water.
The examples of L. proliferum shown here were collected from at the contact of the Haynies Limestone bed (below) and Burr Oak shale bed (above) of the Ervine Creek Limestone member of the Deer Creek Formation near Weeping Water, Cass County, Nebraska.
Description: The twisted example (left) may indicate reorientation of the calyx after the specimen had been tipped over. The middle example shows the columella in the center of the calyx. The example at the right may show an example of asexual cloning, cf. "Pseudozaphrentoides verticillatus" (Barbour).