Cladoselache is an extinct genus of shark-like chondrichthyan from the Late Devonian (Famennian) of North America. It was similar in body shape to modern lamnid sharks, but was not closely related to lamnids or to any other modern (selachian) shark. As an early chondrichthyan, it had yet to evolve traits of modern sharks such as accelerated tooth replacement, a loose jaw suspension, enameloid teeth, and possibly claspers.
Stethacanthus is an extinct genus of shark-like cartilaginous fish which lived from the Late Devonian to Late Carboniferous epoch, dying out around 298.9 million years ago. Fossils have been found in Australia, Asia, Europe and North America.
Xenacanthida is an order or superorder of extinct shark-like chondrichthyans known from the Carboniferous to Triassic. They were native to freshwater, marginal marine and shallow marine habitats. Some xenacanths may have grown to lengths of 5 m (16 ft). Most xenacanths died out at the end of the Permian in the End-Permian Mass Extinction, with only a few forms surviving into the Triassic.
The Bear Gulch Limestone is a limestone-rich geological lens in central Montana, renowned for the quality of its late Mississippian-aged fossils. It is exposed over a number of outcrops northeast of the Big Snowy Mountains, and is often considered a component of the more widespread Heath Formation. The Bear Gulch Limestone reconstructs a diverse, though isolated, marine ecosystem which developed near the end of the Serpukhovian age. It is a lagerstätte, a particular type of rock unit with exceptional fossil preservation of both articulated skeletons and soft tissues. Bear Gulch fossils include a variety of fish, invertebrates, and algae occupying a number of different habitats within a preserved shallow bay.
Belantsea is a genus of extinct petalodontid cartilaginous fish that lived during the Lower Carboniferous, about 350 million years ago. Its fossils are found in the Bear Gulch Limestone lagerstätte. Its body was leaf-shaped, with muscular fins and a small tail. Such a body plan would allow for great maneuverability, but at the cost of speedy cruising. Its few, large, triangular teeth formed a beak-like arrangement that allowed it to graze bryozoans, sponges, crinoids, and other encrusting animals. The genus contains two species, B. montana and B. occidentalis.
Falcatus is an extinct genus of falcatid chondrichthyan which lived during the early Carboniferous Period in Bear Gulch bay in what is now Montana.
Stethacanthidae is an extinct family of prehistoric holocephalians. It is estimated to have existed approximately between 380 and 300 million years ago. Members of this family are noted for their peculiar dorsal fin.
Netsepoye is an extinct genus of cartilaginous fish distantly related to the modern order Chimaeriformes, containing the single species Netspoye hawesi. It lived more than 320 million years ago during the Late Mississippian.
Siksika ottae is an extinct species of petalodont, which lived during the Upper Mississippian. It has been discovered at the well known Carboniferous-aged Bear Gulch Limestone. It is known primarily from fossil teeth, but also from partial neurocranium and mandibles which hint at a close relationship to coeval petalodontiforms such as Janassa and Netsepoye. Dentition is generally heterodont. Siksika translates to Blackfoot, being named after the Siksika Nation.
Glikmanius is an extinct genus of ctenacanth cartilaginous fish which lived in the Carboniferous of North America and Russia. Skeletal remains attributed to the genus are known from Nebraska, USA. Glikmanius is named in honour of the Russian palaeontologist, Dr. Leonid Glikman, who studied the genus and was "the first to propose its ctenacanthiform affinity". G. careforum may have reached lengths of 3 metres (9.8 ft), while G. occidentalis may have reached lengths of over 6 metres (20 ft), making it one the largest marine predators of its time.
Falcatidae is a family of Paleozoic cartilaginous fish belonging to the order Symmoriiformes. Members of this family include Falcatus, a small fish from the Bear Gulch Limestone of Montana. The family first appeared around the start of the Carboniferous, and there is some evidence that they survived well into the early Cretaceous, though its putative Cretaceous members were also argued to be more likely neoselachians.
Hybodontiformes, commonly called hybodonts, are an extinct group of shark-like cartilaginous fish (chondrichthyans) which existed from the late Devonian to the Late Cretaceous. Hybodonts share a close common ancestry with modern sharks and rays (Neoselachii) as part of the clade Euselachii. They are distinguished from other chondrichthyans by their distinctive fin spines and cephalic spines present on the heads of males. An ecologically diverse group, they were abundant in marine and freshwater environments during the late Paleozoic and early Mesozoic, but were rare in open marine environments by the end of the Jurassic, having been largely replaced by modern sharks, though they were still common in freshwater and marginal marine habitats. They survived until the end of the Cretaceous, before going extinct.
The Clackmannan Group is the name given to a suite of rocks of late Dinantian and Namurian age laid down during the Carboniferous period in the Midland Valley of Scotland.
Chomatodus is a prehistoric cartilaginous fish genus.
Ctenacanthus is an extinct genus of ctenacanthiform chondrichthyan. Remains have been found in the Bloyd Formation of Arkansas and the Cleveland Shale of Ohio in the United States and in South America.
Ctenacanthiformes is an extinct order of cartilaginous fish. They possessed ornamented fin spines at the front of their dorsal fins and cladodont-type dentition, that is typically of a grasping morphology, though some taxa developed cutting and gouging tooth morphologies. Some ctenacanths are thought to have reached sizes comparable to the great white shark, with body lengths of up to 7 metres (23 ft) and weights of 1,500–2,500 kilograms (3,300–5,500 lb). The earliest ctenacanths appeared during the Frasnian stage of the Late Devonian, with the group reaching their greatest diversity during the Early Carboniferous (Mississippian), and continued to exist into at least the Middle Permian (Guadalupian). Some authors have suggested members of the family Ctenacanthidae may have survived into the Cretaceous based on teeth found in deep water deposits of Valanginian age in France and Austria, however, other authors contend that the similarity of these teeth to Paleozoic ctenacanths is only superficial, and they likely belong to neoselachians instead.
Saivodus is an extinct genus of ctenacanthiform fish that existed in early Mississippian of the Carboniferous period. Fossils have been found in Ireland, Scotland, England, Belgium, Morocco, and the United States. Teeth assigned to that genus are also known from the Permian (Leonardian) Kaibab Formation.
Anachronistidae is an extinct family of cartilaginous fish, known from the Carboniferous and Permian periods. They are considered to be the oldest known members of Neoselachii, with a close relationship to modern sharks and rays. They are known from isolated teeth. They first appeared in Europe during the late Mississippian (Viséan), with Cooleyella dispersing into North America and South America during the Late Carboniferous and Permian.
Cosmoselachus is an extinct genus of symmoriiform chondrichthyan from the Upper Carboniferous aged Fayetteville Shale of Arkansas, United States. The genus contains a single species, C. mehlingi, which is known from a partial specimen that includes the cranium, jaws, gill arches, pectoral fins, and teeth.
