Chondrichthyes is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or bony fish, which have skeletons primarily composed of bone tissue. Chondrichthyes are aquatic vertebrates with paired fins, paired nares, placoid scales, conus arteriosus in the heart, and a lack of opercula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates.
A barracuda is a large, predatory, ray-finned fish known for its fearsome appearance and ferocious behaviour. The barracuda is a saltwater fish of the genus Sphyraena, the only genus in the family Sphyraenidae, which was named by Constantine Samuel Rafinesque in 1815. It is found in tropical and subtropical oceans worldwide ranging from the eastern border of the Atlantic Ocean to the Red Sea, on its western border the Caribbean Sea, and in tropical areas of the Pacific Ocean. Barracudas reside near the top of the water and near coral reefs and sea grasses. Barracudas are targeted by sport-fishing enthusiasts.
Acanthodii or acanthodians is an extinct class of gnathostomes. They are currently considered to represent a paraphyletic grade of various fish lineages basal to extant Chondrichthyes, which includes living sharks, rays, and chimaeras. Acanthodians possess a mosaic of features shared with both osteichthyans and chondrichthyans. In general body shape, they were similar to modern sharks, but their epidermis was covered with tiny rhomboid platelets like the scales of holosteians.
Xenacanthus is an extinct genus of xenacanth cartilaginous fish. It lived in freshwater environments, and fossils of various species have been found worldwide.
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.
Climatius is an extinct genus of spiny shark. This genus is known from the Early Devonian (Lochkovian) of Europe, previously considered Silurian remains actually belong to Nostolepis instead.
Acanthodes is an extinct genus of acanthodian fish. Species have been found in Europe, North America, and Asia, spanning the Early Carboniferous to the Early Permian, making it one of the youngest known acanthodian genera.
Mesacanthus is an extinct genus of acanthodian fish from Devonian Scotland. It is among the more primitive of the Devonian acanthodians.
Helicolenus percoides, the reef ocean perch, coral cod, coral perch, Jock Stewart, kuriarki, ocean perch, red gurnard perch, red gurnard scorpionfish, red ocean perch, red perch, red rock perch, scarpee or sea perch, is a species of marine ray-finned fish belonging to the subfamily Sebastinae, part of the family Scorpaenidae. It is found in the southwestern Pacific Ocean.
Cheiracanthus is an extinct genus of a group of fish called Acanthodii. It was a deep-bodied acanthodian about 12 in. (30 cm) in length. It had a blunt head, upturned tail, and fins protected by spines. Unlike many other acanthodians, it had one, solitary dorsal fin. Cheiracanthus swam at mid-depth in lakes and rivers, seizing small prey in its gaping jaws. Whole fossils of this fish occur only in Mid-Devonian rocks in Scotland, but its distinctive small, ornamented scales crop up around the world, as far south as Antarctica.
The yellowspotted trevally, also known as the yellowspotted kingfish, goldspotted trevally, tarrum, or yellowspot, is a widespread species of large inshore marine fish in the jack family Carangidae. The yellowspotted trevally inhabits the tropical and subtropical waters of the western Indo-Pacific region, from South Africa in the west to Japan and Australia in the east. The species is known to grow to a maximum length of at least 1.2 m, and is distinguished by gill raker and fin morphology, as well as the distinctive golden spots which give the fish its name. The yellowspotted trevally generally prefers inshore rocky and coral reefs, but is occasionally found over deep offshore sand banks to a depth of 100 m. It is a predatory fish, taking fish, cephalopods, and crustaceans, and shows diet partitioning with other trevallies in studies conducted in Australian waters. Reproduction is poorly studied, although observational evidence suggests spawning occurs in aggregations, probably during summer in South Africa. It is generally of minor importance to commercial fisheries throughout its range, but is considered an excellent sportfish by anglers and spearfishermen, and a good table fish.
Cryptacanthodes is a genus of marine ray-finned fishes belonging to the monogeneric family Cryptacanthodidae, commonly referred to as wrymouths. Three of the four species are found in the Pacific Ocean with one species native to the western Atlantic Ocean where they are benthic fishes, tunneling through soft substrates. It is currently the only known genus in its family.
Altenglanerpeton is an extinct genus of microsaur tetrapod from the Late Carboniferous or Early Permian of Germany. Altenglanerpeton was named in 2012 after the Altenglan Formation in which it was found. The type and only species is A. schroederi.
Brochoadmones is an extinct genus of acanthodian from the Devonian of what is now Canada. It is the only genus in the suborder Brochoadmonoidei, whose relationship to other acanthodian orders remains currently in flux.
Pristipomoides is a genus of marine ray-finned fish belonging to the family Lutjanidae, the snappers. They are found in the Atlantic, Indian and Pacific oceans.
Carlastyanax aurocaudatus is a small species of freshwater fish in the family Characidae native to the Río Cauca in Colombia. It is the only member of the monotypic genus Carlastyanax, which was named in 1972 specifically for the species by Jacques Géry. Upon description, it was named Astyanax aurocaudatus by Carl H. Eigenmann. There has been debate concerning whether or not the genus should be recognized, but C. aurocaudatus is currently considered a valid species.
Ptomacanthus is an extinct genus of spiny shark, an early relative of living cartilaginous fishes.
Zaniolepis frenata, also known as the shortspine combfish, is a species of ray-finned fish belonging to the family Zaniolepididae.The species occurs in the eastern Pacific Ocean.
Achanarella is a genus of extinct jawless fish from the Achanarras Quarry in Scotland, dating to the Middle Devonian. The only known species in the genus is Achanarella trewini.
