Elasmobranchii is a subclass of Chondrichthyes or cartilaginous fish, including sharks, rays, skates, and sawfish. Members of this subclass are characterised by having five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. The details of this jaw anatomy vary between species, and help distinguish the different elasmobranch clades. The pelvic fins in males are modified to create claspers for the transfer of sperm. There is no swim bladder; instead, these fish maintain buoyancy with large livers rich in oil.
The Ganges shark is a critically endangered species of requiem shark found in the Ganges River and the Brahmaputra River of India and Bangladesh. It is often confused with the more common bull shark, which also inhabits the Ganges River and is sometimes incorrectly referred to as the Ganges shark. The genus is currently considered to contain three recent species; genetic evidence has shown that both the Borneo river shark and Irrawaddy river shark should be regarded as synonyms of the Ganges shark, expanding the range of the species to Pakistan, Myanmar, Borneo, and Java. While the other members of the genus Glyphis occur in coastal marine waters as well as rivers, the Ganges shark is found only in fresh water, making it the world's only exclusively freshwater shark. The species remains poorly known and very rare.
The sapayoa or broad-billed sapayoa is a suboscine passerine bird found Colombia, Ecuador, and Panama.
The bramble shark is one of the two species of sharks in the family Echinorhinidae. Aside from the eastern Pacific Ocean, it is found in tropical and temperate waters worldwide. This rarely encountered shark swims close to the bottom of the seafloor, typically at depths of 400–900 m (1,300–3,000 ft), though it may enter much shallower water. The bramble shark has a stout body with two small dorsal fins positioned far back and no anal fin. It can be readily identified by the large, thorn-like dermal denticles scattered over its body, some of which may be fused together. It is purplish brown or black in color and grows up to 3.1 m (10 ft) long.
The New Zealand smooth skate is a skate of the genus Dipturus, found around New Zealand at depths between 15 and 1,300 m.
The prickly deep-sea skate, or spinydeep-sea skate, is a deep sea skate in the family Arhynchobatidae. It lives off New Zealand, at depths of from 170 to 1,400 m on the continental shelf. Their length is from 60 to 80 cm.
The bigeye sand tiger is an extremely rare species of mackerel shark in the family Odontaspididae, with a possible worldwide distribution. A large, bulky species reaching at least 3.6 m (12 ft) in length, the bigeye sand tiger has a long bulbous snout, large orange eyes without nictitating membranes, and a capacious mouth with the narrow teeth prominently exposed. It can be distinguished from the similar smalltooth sand tiger by its teeth, which have only one lateral cusplet on each side, and by its uniformly dark brown color.
The smalleyed ray or smalleyed skate is a species of ray in the family Rajidae, the typical rays and skates, from the eastern Atlantic Ocean where it is found in tidal, coastal waters with sandy substrates.
Arhynchobatidae is a family of skates whose members are commonly known as the softnose skates. It belongs to the order Rajiformes in the superorder Batoidea of rays. At least 104 species have been described, in 13 genera. Softnose skates have at times been placed in the same family as hardnose skates, but most recent authors recognize them as a distinct family. Members of the Arhynchobatidae can be distinguished from hardnose skates in having a soft and flexible snout, as well as a more or less reduced rostrum.
Capoeta angorae is a species of freshwater cyprinid fish, which is known from a single specimen caught from Turkey. that was 42 cm long. It is also known as the Ankara barb. Not much can be said about its biology, distribution and future therefore.
The mottled skate is a species of skate in the family Rajidae. An inhabitant of shallow coastal waters, it is found in the northwestern Pacific Ocean off Korea, Japan, and China. This species grows to 1.12 m (3.7 ft) long and has a diamond-shaped pectoral fin disc with a long snout. It is characterized by a covering of prickles above and below its snout, but not elsewhere on its body, and a dark ring in the middle of each "wing".
Gillellus inescatus, the flagfin stargazer, is a species of tropical sand stargazer native to the Caribbean sea.
Brochiraja is a genus of deep-sea skates in the family Arhynchobatidae containing eight species. They are found in the waters around New Zealand and the Tasman Sea.
The Peruvian skate is a large skate found in the southeast Pacific Ocean, off the coasts of Peru, Ecuador, and Chile. It can grow to an estimated 1.1 metres total length, and 1.25 m across. It is known to be a deepwater species; the holotype was caught at a depth of 908 m (2,979 ft), and is generally found at depths of 600–1,100 m (2,000–3,600 ft). Very little is known about its biology.
The pita skate is a medium-sized skate in the family Rajidae. The holotype and only known specimen was found in the northern Persian Gulf, in Iraqi waters. It was collected at a depth of less than 15 m (49 ft).
Amblyraja reversa, commonly known as the reversed skate, is a deepwater skate known from a single specimen. Based on the single specimen, its range is predicted to include at least the Western Indian Ocean, specifically the Baluchistan coast in the Arabian Sea.
Psammobatis parvacauda, commonly known as the smalltail sandskate, is a skate in the family Arhynchobatidae. Based on the single known specimen, its range includes at least the area northeast of the Falkland Islands.
Gurgesiella atlantica, commonly known as the Atlantic pygmy skate, Atlantic finless skate, or simply the Atlantic skate, is a skate species in the family Gurgesiellidae. It lives in the western central and southwest Atlantic Ocean, from Nicaragua to Brazil. It grows to 49 centimetres (19 in) – 52 centimetres (20 in) long and is distinguished from other skates by its long, slender tail and absence of dorsal fins.
Andamia cyclocheilus is a species of combtooth blenny which is known from a single specimen from Atjatuning, western New Guinea. The IUCN rate it as Data Deficient because its taxonomy is unclear. It is associated with reefs.
The Sydney skate is a species of skate of the family Rajidae native to waters off the east coast of Australia.
