描述Kallidecthes richardsoni fossil shrimp (Mazon Creek Lagerstatte, Francis Creek Shale, Middle Pennsylvanian; coal mine dump pile near Essex, northern Illinois, USA).jpg |
Kallidecthes richardsoni Schram, 1969 fossil shrimp from the Pennsylvanian of Illinois, USA (public display, FMNH PE 37598, Field Museum of Natural History, Chicago, Illinois, USA).
One of the most remarkable soft-bodied fossil deposits (lagerstätten) on Earth is the Pennsylvanian-aged Mazon Creek Lagerstätte near Chicago, Illinois. In the Mazon Creek area, the Francis Creek Shale consists of concretionary gray shales. The Francis Creek concretions are composed of argillaceous ironstone, and can be fossiliferous or nonfossiliferous. The fossiliferous concretions contain land plants and terrestrial & marine animals, including nonmineralizing organisms.
This Kallidecthes richardsoni specimen is a laterally compressed fossil shrimp in a Mazon Creek concretion.
Classification: Animalia, Arthropoda, Crustacea, Malacostraca, Hoplocarida, Aeschronectida
Stratigraphy: Mazon Creek Lagerstätte, Francis Creek Shale Member, Carbondale Formation, Desmoinesian Stage (= Westphalian D), upper Middle Pennsylvanian
Locality: coal mine dump pile near Essex, northern Illinois, USA |