Caridosuctor Bear Gulch Lagerstätte Coelacanth

Caridosuctor populosum

Class Sarcopterygii, Subclass, Coelacanthimorpha, Order Coelacanthiformes, Family Rhabdodermatidae

Geological Time: Mississippian (~320 m.y.a.)

Size: Fossil Fish: 120 mm long

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

Caridosuctor populosumDescription: The Bear Gulch Limestone is a Lagerstätte Fossil Site of some 70 square kilometers in extent and 30 meters depth that has been a source of one of an extremely diverse assemblage of fish fossils. Some 110 species having been described over the past 30 years. Most were new to science, and provided a new window into the marine environment of Mississippian times. Fine preservation of both fish and invertebrates is exhibited of these deposits, ostensible due to an anoxic Coelacanth depositional environment. This specimen is a coelacanth known as Caridoscuctor (“shrimp eater”), and is well-represented in the Bear Gulch deposits. Specimens found range from 30 mm to 250 mm in length. They exhibit sexual dimorphism, with larger, more robust females and smaller, more gracile males, a characteristic also seen in the modern coelacanth Latimeria. The species Caridosuctor populosum died out during the Lower Carboniferous. The preservation of this specimen is exquisite.

Also see: Sarcoptergyii Fish Fossils

click to enlarge fossil pictures


Fossil Museum Navigation:
Fossils Home
Geological Time Paleobiology Geological History Tree of Life
Fossil Sites Fossils Evolution Fossil Record Museum Fossils