The Sarcopterygii or lobe-finned fish —sometimes considered synonymous with Crossopterygii —constitute a clade of the bony fish, though a strict cladistic view includes the terrestrial vertebrates.
Actinistia is a subclass of mostly fossil lobe-finned fishes. This subclass contains the coelacanths, including the two living species of coelacanths, both of the genus Latimeria: the West Indian Ocean coelacanth and the Indonesian coelacanth.
The cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the cingulate sulcus. The cingulate cortex is usually considered part of the limbic lobe.
Brodmann area 11 is one of Brodmann's cytologically defined regions of the brain. It is in the orbitofrontal cortex which is above the eye sockets (orbitae). It is involved in decision making and processing rewards, planning, encoding new information into long-term memory, and reasoning.
Latimeria is a rare genus of fish that includes two extant species: West Indian Ocean coelacanth and the Indonesian coelacanth. They follow the oldest known living lineage of Sarcopterygii, which means they are more closely related to lungfish, reptiles and mammals than to the common ray-finned fishes.
An electric fish is any fish that can generate electric fields. A fish that can generate electric fields is said to be electrogenic while a fish that has the ability to detect electric fields is said to be electroreceptive. Most electrogenic fish are also electroreceptive. Electric fish species can be found both in the ocean and in freshwater rivers of South America (Gymnotiformes) and Africa (Mormyridae). Many fish such as sharks, rays and catfishes can detect electric fields and are thus electroreceptive, but they are not classified as electric fish because they cannot generate electricity. Most common bony fish (teleosts), including most fish kept in aquaria or caught for food, are neither electrogenic nor electroreceptive.
The median portion of the wall of the forebrain consists of a thin lamina, the lamina terminalis, which stretches from the Interventricular foramen to the recess at the base of the optic stalk and contains the vascular organ of the lamina terminalis, which regulates the osmotic concentration of the blood. The lamina terminalis is immediately anterior to the tuber cinereum; together they form the pituitary stalk.
The West Indian Ocean coelacanth, sometimes known as gombessa, African coelacanth, or simply coelacanth, is one of two extant species of coelacanth, a rare order of vertebrates more closely related to lungfish, reptiles and mammals than to the common ray-finned fishes. It has a vivid blue pigment, and is the better known of the two extant species. The species has been assessed as critically endangered on the IUCN Red List.
The smalltooth sawfish is a species of sawfish in the family Pristidae. It is found in shallow tropical and subtropical waters in coastal and estuarine parts of the Atlantic. Reports from elsewhere are now believed to be misidentifications of other species of sawfish. It is a critically endangered species that has disappeared from much of its historical range.
Discosauriscus was a small reptiliomorph, It lived in what is now Central and Western Europe in the Early Permian Period. Its best fossils have been found in Boskovice Furrow, in the Czech Republic.
The Indonesian coelacanth is one of two living species of coelacanth, identifiable by its brown color. It is listed as vulnerable by the IUCN. The other species, L. chalumnae is listed as critically endangered.
In mammals, the Bötzinger complex (BötC) is a group of neurons located in the rostral ventrolateral medulla, and ventral respiratory column. In the medulla, this group is located caudally to the facial nucleus and ventral to nucleus ambiguous.
The rostral spinocerebellar tract is a tract which transmits information from the golgi tendon organs of the cranial half of the body to the cerebellum. It terminates bilaterally in the anterior lobe of the cerebellum after travelling ipsilaterally from its origin in the cervical portion of the spinal cord. It reaches the cerebellum partly through the brachium conjunctivum and partly through the restiform body.
Gryposuchus is an extinct genus of gavialoid crocodilian. It is the type genus of the subfamily Gryposuchinae. Fossils have been found from Argentina, Colombia, Venezuela, Brazil and the Peruvian Amazon. The genus existed from the Middle Miocene to Late Pleistocene. One recently described species, G. croizati, grew to an estimated length of 10 metres (33 ft).
Jamming avoidance response (JAR) is a behavior performed by some species of weakly electric fish. The JAR occurs when two electric fish with wave discharges meet – if their discharge frequencies are very similar, each fish will shift its discharge frequency to increase the difference between the two fish's discharge frequencies. By doing this, both fish prevent jamming of their sense of electroreception.
Passive electrolocation is a process where certain species of fish or aquatic amphibians can detect electric fields using specialized electroreceptors to detect and to locate the source of an external electric field in its environment creating the electric field. These external electric fields can be produced by any bioelectrical process in an organism, especially by actions of the nerves or muscles of fish, or indeed by the specially developed electric organs of fish. Other fields are induced by movement of a conducting organism through the earth's magnetic field, or from atmospheric electricity.
Fins are usually the most distinctive anatomical features of a fish. They are composed of bony spines or rays protruding from the body with skin covering them and joining them together, either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as seen in sharks. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles. Their principal function is to help the fish swim. Fins located in different places on the fish serve different purposes such as moving forward, turning, keeping an upright position or stopping. Most fish use fins when swimming, flying fish use pectoral fins for gliding, and frogfish use them for crawling. Fins can also be used for other purposes; male sharks and mosquitofish use a modified fin to deliver sperm, thresher sharks use their caudal fin to stun prey, reef stonefish have spines in their dorsal fins that inject venom, anglerfish use the first spine of their dorsal fin like a fishing rod to lure prey, and triggerfish avoid predators by squeezing into coral crevices and using spines in their fins to lock themselves in place.
