Tyrannophontes Bear Gulch Fossil Mantis Shrimp Precursor

Tyrannophontes theridion

Subphylum Crustacea, Class Malacostraca, Family Tyrannophontidae

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

Size: Fossil is 93 mm (curve measure); Matrix: 150 mm by 153 mm

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

Code: BGF566

Price: Sold


Tyrannophontes Bear Gulch Fossil Mantis Shrimp PrecursorDescription: 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 Tyrannophontespast 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 a protomantis known as Tyrannophontes theridion. It is also known from the younger Mazon Creek deposits of Illinois. The modern Mantis Shrimps are rapacious carnivores that employ a slash and grab lifestyle. Presumably this taxon shared that same modus operandi. This one is a counterpart example with fine details. It is one of the largest I have ever come across. Interestingly, those from Mazon Creek are typically only about one fourth this size.

Fossils for Sale Information

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