The Mazon Creek fossil beds are a conservation lagerstätte found near Morris, in Grundy County, Illinois. The fossils are preserved in ironstone concretions, formed approximately 309 million years ago in the mid-Pennsylvanian epoch of the Carboniferous period. These concretions frequently preserve both hard and soft tissues of animal and plant materials, as well as many soft-bodied organisms that do not normally fossilize. The quality, quantity and diversity of fossils in the area, known since the mid-nineteenth century, make the Mazon Creek lagerstätte important to paleontologists attempting to reconstruct the paleoecology of the sites. The locality was declared a National Historic Landmark in 1997.
Helenodora is an extinct basal onychophoran or lobopodian genus known from the Carboniferous Carbondale Formation of Illinois. The only known species described is H. inopinata. The ecology of this animal is not well known, but it is thought that it may have lived on land and/or underwater.
Pseudophlegethontia is an extinct genus of aïstopod tetrapodomorphs. It is the only member of the family Pseudophlegethontiidae. The only species is the type species P. turnbullorum, named in 2003. Fossils of Pseudophlegethontia have been found from the Mazon Creek fossil beds in Grundy County, Illinois, a conservation lagerstätte well known for the exceptional preservation of middle Pennsylvanian taxa.
Cornuboniscus is an extinct genus of prehistoric freshwater ray-finned fish that lived during the Pennsylvanian epoch (Carboniferous), and the only member of the family Cornuboniscidae. It contains a single species, C. budensis from the Bashkirian/lower Westphalian age of what is now Cornwall, England. The genus Cornubonisus was named after the island of Cornubian, and the species name refers to the coastal town of Bude in Cornwall. The type specimen is held in the town's Castle Heritage Centre.
Brachypareion is an extinct genus of prehistoric marine ray-finned fish that lived during the Pennsylvanian epoch. It contains a single species, B. insperatum, known from the Saur Mountains of Kazakhstan. It is placed in the paraphyletic group Palaeonisciformes.
Palaeophichthys is an extinct genus of prehistoric bony fish that lived during the Desmoinsian stage of the Pennsylvanian epoch.
Haplolepis is an extinct genus of prehistoric ray-finned fish that lived during the late Moscovian Stage of the Pennsylvanian Period. Well-preserved specimens are known from the Lagerstätte in the Upper Freeport Coal at Linton, Ohio, and were first described by John Strong Newberry in the 1800s.
Illiniichthys is an extinct genus of prehistoric bony fish that lived during the late Moscovian stage of the Pennsylvanian epoch in what is now Illinois, United States. Fossils were collected from the Mazon Creek fossil beds. The genus is named after the Illini Native American tribe.
Synaptotylus is an extinct genus of prehistoric sarcopterygians or lobe-finned fish from the Pennsylvanian. The type species is Synaptotylus newelli.
Igornella is an extinct genus of prehistoric bony fish that lived during the Gzhelian (Stephanian) to Asselian ages in what is now France (Burgundy).
Phanerosteon is an extinct genus of prehistoric bony fish from the Carboniferous period. The type species, P. mirabile, was recovered from the Calciferous sandstone series (Pennsylvanian), Scotland. A second species, P. phonax was described from the Serpukhovian aged Bear Gulch Limestone lagerstätte in Montana, United States.
Paralbula is an extinct genus of prehistoric bony fish. They can be found in the Hell Creek Formation, in Montana, United States.
Belotelson is a genus of crustaceans, in the extinct order Belotelsonidea, containing at least two species. It was first named by Packard in 1886 from material found in the Mazon Creek lagerstätte in Illinois. Its fossils have been found in Pennsylvanian age rocks.
Guntherichthys is an extinct genus of prehistoric bony fish that lived during the late Mississippian/early Pennsylvanian in what is now Utah, United States. Fossils were recovered from the Manning Canyon Shale. The genus is named after Lloyd Gunther.
Spinofacia is an extinct genus of prehistoric bony fish that lived during the late Mississippian/early Pennsylvanian in what is now Utah, United States. Fossils were recovered from the Manning Canyon Shale.
Paleontology in Illinois refers to paleontological research occurring within or conducted by people from the U.S. state of Illinois. Scientists have found that Illinois was covered by a sea during the Paleozoic Era. Over time this sea was inhabited by animals including brachiopods, clams, corals, crinoids, sea snails, sponges, and trilobites.
Pipiscius is an extinct genus of lamprey that lived about 300 million years ago, during the Middle Pennsylvanian Epoch of the Carboniferous Period. The genus contains a single species, P. zangerli, known from the Mazon Creek fossil beds located in present-day Illinois.
Bandringa is an extinct genus of elasmobranch known from the Pennsylvanian subperiod of the Carboniferous period that was part of the monotypic family Bandringidae. There is currently a single known species, B. rayi, described in 1969. It is known from exceptionally preserved individuals found in the Mazon Creek Lagerstätte of Illinois which dates back to the late Moscovian stage.
Tyrannophontes is an extinct genus of mantis shrimp that lived during the late Carboniferous period in what is now the Mazon Creek fossil beds of Illinois. It is the only genus in the family Tyrannophontidae. The type species, T. theridion, was described in 1969 by Frederick Schram. A second, much larger species, T. gigantion, was also named by Schram in 2007. Two other species were formerly assigned to the genus, but have since been reclassified.
Douglassarachne is an extinct genus of arachnid from the Late Carboniferous (Moscovian), known from single species D. acanthopoda. It is known exclusively from one specimen recovered from the Mazon Creek Lagerstätte, Illinois, US.
