Fine Mississippian Bear Gulch Fossil Orthocone Nautiloid

Part and Counterpart Specimen

Reticycloceras sp

Class Cephalopoda, Subclass Nautiloidea, Order Nautilida, Family Pseudorthoceratidae

Geological Time: Mississippian (~ million years ago)

Size: Fossil is 80 mm long by 20 mm across Matrix: 120 mm by 50 mm and 110 mm by 80 mm pair

Fossil Site: Heath Shale Formation, Bear Gulch Limestone, Fergus County, Montana

Fossil Code: BGF155

Price: Sold

Reticycloceras FossilDescription: The Bear Gulch Limestone is a deposit of some 70 square km in extent and 30 m in depth that has been a source of one of the most diverse assemblages of fossil fish with some 110 species having been described over the past 30 years. Most were new to science, and provided a unique view of the marine environment of Mississippian times. Fine preservation of both fish and invertebrates is a hallmark of these deposits, presumably due to an anoxic depositional environment. This specimen is an orthocone nautilod known as Reticycloceras. The orthocones derive their name from their essentially straight shell; some from the Ordovician and Silurian reached lengths of 3 meters.

Fossils Purchase Information

click pictures to enlarge

Fossil Mall Navigation:
l Home l Fossils for Sale Map l Museum and Rare Fossils l How to Buy Fossils l

Navigate by Fossil Category:
l Trilobites
l Ammonites l Fish Fossils l Invertebrate Fossils l
l Crinoids and Echinoderms l Insect Fossils l Dinosaur and Reptile Fossils l
l Cambrian Explosion Fossils l Plant Fossils l Stromatolites l
l Vertebrate Fossils l Fossil Amber l Trace & Ichnofossils l

l Fossils and Paleotological Science Information l