Cnidaria, is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, including jellyfish, hydroids, sea anemones, corals and some of the smallest marine parasites. Their distinguishing features are a decentralized nervous system distributed throughout a gelatinous body and the presence of cnidocytes or cnidoblasts, specialized cells with ejectable flagella used mainly for envenomation and capturing prey. Their bodies consist of mesoglea, a non-living, jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. Cnidarians are also some of the only animals that can reproduce both sexually and asexually.
The bullhead sharks are members of the genus Heterodontus, the only members of the family Heterodontidae and only living members of the order Heterodontiformes. All are relatively small, with the largest species reaching just 1.65 metres (5.5 ft) in maximum length. They are bottom feeders in tropical and subtropical waters.
Carettochelyidae is a family of cryptodiran turtles belonging to the Trionychia. It contains only a single living species, the pig-nosed turtle native to New Guinea and Northern Australia. Stem-group carettochelyids are known from the Cretaceous of Asia, with the family being widely distributed across North America, Europe, Asia and Africa during much of the Cenozoic.
Tullimonstrum, colloquially known as the Tully monster or sometimes Tully's monster, is an extinct genus of soft-bodied bilaterian animal that lived in shallow tropical coastal waters of muddy estuaries during the Pennsylvanian geological period, about 300 million years ago. A single species, T. gregarium, is known. Examples of Tullimonstrum have been found only in the Essex biota, a smaller section of the Mazon Creek fossil beds of Illinois, United States. Its classification has been the subject of controversy, and interpretations of the fossil have likened it to molluscs, arthropods, conodonts, worms, tunicates, and vertebrates. This creature had a mostly cigar shaped body, with a triangular tail fin, two long stalked eyes, and a proboscis tipped with a mouth-like appendage. Based on the fossils, it seems this creature was a nektonic carnivore that hunted in the ocean’s water column. When Tullimonstrum was alive, Illinois was a mixture of ecosystems like muddy estuaries, marine environments, and rivers and lakes. Fossils of other organisms like crustacean Belotelson, the cnidarian Essexella, and the elasmobranch fish Bandringa have been found alongside Tullimonstrum.
Limulus is a genus of horseshoe crab, with one extant species, the Atlantic horseshoe crab. One fossil species is currently assigned to the genus though several other species have been named, which have since been assigned to other genera.
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.
The Hunsrück Slate is a Lower Devonian lithostratigraphic unit, a type of rock strata, in the German regions of the Hunsrück and Taunus. It is a lagerstätte famous for exceptional preservation of a highly diverse fossil fauna assemblage.
Mesolimulus is an extinct genus of horseshoe crab. The best known examples are found in Solnhofen limestone near Solnhofen, Bavaria, Germany. Originally assigned to the living genus Limulus, they are related to and look virtually identical to modern horseshoe crabs. Other species assigned to Mesolimulus have been recorded spanning over 140 million years from the Middle Triassic to Late Cretaceous from England, Spain, Siberia and Morocco.
The Thylacocephala are group of extinct probable mandibulate arthropods, that have been considered by some researchers as having possible crustacean affinities. As a class they have a short research history, having been erected in the early 1980s.
Procolophonidae is an extinct family of small, lizard-like parareptiles known from the Late Permian to Late Triassic that were distributed across Pangaea, having been reported from Europe, North America, China, South Africa, South America, Antarctica and Australia. The most primitive procolophonids were likely insectiovous or omnivorous, more derived members of the clade developed bicusped molars, and were likely herbivorous feeding on high fiber vegetation or durophagous omnivores. Many members of the group are noted for spines projecting from the quadratojugal bone of the skull, which likely served a defensive purpose as well as possibly also for display. At least some taxa were likely fossorial burrowers. While diverse during the Early and Middle Triassic, they had very low diversity during the Late Triassic, and were extinct by the beginning of the Jurassic.
Pohlsepia mazonensis is a species of fossil organism with unknown affinity. Although it was originally identified as an extinct cephalopod, later studies denied that interpretation. The species is known from a single exceptionally preserved fossil discovered in the late Carboniferous (Pennsylvanian) Francis Creek Shale of the Carbondale Formation, north-east Illinois, United States.
Falcatus is an extinct genus of falcatid chondrichthyan which lived during the early Carboniferous Period in Bear Gulch bay in what is now Montana.
Tachypleus is a genus of south, southeast and east Asian horseshoe crabs in the family Limulidae.
The Toolebuc Formation is a geological formation that extends from Queensland across South Australia and the Northern Territory in Australia, whose strata date back to the Albian stage of the Early Cretaceous. Dinosaurs, pterosaurs, plesiosaurs, ichthyosaurs, protostegid turtles, sharks, chimaeroids and bony fish remains are among the fossils that have been recovered from the formation.
Archaeopriapulida is a group of priapulid worms known from Cambrian lagerstätte. The group is closely related to, and very similar to, the modern Priapulids. It is unclear whether it is mono- or polyphyletic. Despite a remarkable morphological similarity to their modern cousins, they fall outside of the priapulid crown group, which is not unambiguously represented in the fossil record until the Carboniferous. In addition to well-preserved body fossils, remains of several archaeopriapulid taxa are known to have been preserved primarily as organic microfossils, such as isolated scalids and pharyngeal teeth. They are probably closely related or paraphyletic to the palaeoscolecids; the relationship between these basal worms is somewhat unresolved.
Asteracanthus is an extinct genus of hybodont, known from the Middle Jurassic (Bathonian) to the Early Cretaceous (Valanginian).
Haliestes is a genus of sea spider from the Silurian aged Coalbrookdale Formation of England. It contains a single species, Haliestes dasos. The species was first described by David Siveter et al. in 2004. It is considered to be a nektonic predator.
Reticulomedusa is an extinct genus of prehistoric cnidarian containing a single species, Reticulomedusa greenei. It is known from the Mazon Creek located in Illinois. Although it was once described as jellyfish, it may be pedal or oral disc of Essexella which is reinterpreted as sea anemone.
Octomedusa is a genus of extinct scyphozoan jellyfish known from the Late Carboniferous sediments of the Mazon Creek fossil beds. It contains a single species, O. pieckorum. It was first described by Gordon Johnson and Eugene S. Richardson, Jr. in 1968, where its holotype and paratype being unearthed by Mr. and Mrs. Ted Piecko. Fossils of the jellyfish occur and other organisms occur in iron-stone concentrations. Octomedusa was described by Foster (1979) as representing a primitive coronate, however these affinities have been challenged and Octomedusa has had many more affinities after. O. pieckorum is the type species of the genus Octomedusa
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. Another species, T. acanthocercus from the Bear Gulch Limestone of Montana, was formerly assigned to Tyrannophontes, but has now been moved to the genus Daidal.
