What do coelacanths eat

It's estimated they can live up to 60 years or more. There are two living species of coelacanth, and both are rare. The West Indian Ocean coelacanth Latimeria chalumnae lives off the east coast of Africa, while the Indonesian coelacanth Latimeria menadoensis is found in the waters off Sulawesi, Indonesia. They are the sole remaining representatives of a once widespread family of lobe-finned fishes; more than species are known from the fossil record.

Coelacanths were thought to be extinct until a live one was caught in Coelacanths were known only from fossils until a live Latimeria chalumnae was discovered off the coast of South Africa in Until then, they were presumed to have gone extinct in the late Cretaceous period, over 65 million years ago.

The second living species of coelacanth, Latimeria menadoensis , was discovered in an Indonesian market in , and a live specimen was caught one year later. Coelacanths might be important for understanding the transition from water to land. Coelacanths were thought to be the ancestors of tetrapods four-legged, land-living animals , but a recent analysis of the coelacanth genome suggests that lungfish are actually more closely related to tetrapods.

The divergence of coelacanths, lungfish, and tetrapods is thought to have occurred about million years ago. Coelacanths might occupy a side branch of the vertebrate lineage, closely related to, yet distinct from, the ancestor of tetrapods. Coelacanths have a unique form of locomotion. One striking feature of the coelacanth is its four fleshy fins, which extend away from its body like limbs and move in an alternating pattern.

The movement of alternate paired fins resembles the movement of the forelegs and hindlegs of a tetrapod walking on land. Their jaws are hinged to open wide.

Unique to any other living animal, the coelacanth has an intracranial joint, a hinge in its skull that allows it to open its mouth extremely wide to consume large prey. It is believed that both species are in grave danger of extinction. The only direct cause of population decline that we know of at the moment is accidental captures while fishing for oilfish. Continued population decline and accidental captures have caused scientists and government officials to begin designing Tanga Coelacanth Marine Park in an effort to protect important populations and their habitats.

It would be virtually impossible to capture, transport, care for, and keep a coelacanth alive as a pet. There have never been any coelacanths in aquariums. We know virtually nothing about what it takes to keep one of these fish alive in human care. During the day, coelacanths rest in underwater caves and crevices. This behavior allows them to conserve energy because they do not have to swim against any currents in protected caves.

At night they drift in search of food before returning to caves again during the day. They are solitary while feeding, but will congregate in groups within caves.

We know very little about the reproduction methods of these fish. Other unique anatomical features include a hollow fluid-filled "notochord" a primitive feature in vertebrates underlying the spinal cord and extending the length of the body, vertebrae that are incompletely formed or totally lacking bony centra, an oil-filled gas bladder, fleshy "lobed" or limb-like fins that are internally supported by bone, and paired fins that move in a synchronized tetrapod-like pattern.

The first living coelacanth was discovered in and bears the scientific name Latimeria chalumnae. The species was described by Professor J. Smith in and was named after its discoverer, Miss Marjorie Courtenay-Latimer. Although Latimeria is a genus distinct from the fossil forms, all coelacanths share numerous features and are easily recognized by their distinctive shape and lobed fins.

For many years, living coelacanths were known only from the western Indian Ocean, primarily from the Comoros Islands, but in September and again in July , coelacanths were captured in northern Sulawesi, Indonesia, nearly 6, miles to the east of the Comoros.

The Indonesian discovery was made by Mark V. Erdmann, then a doctoral student from UC Berkeley studying coral reef ecology in Indonesia.

Although the Indonesian specimens superficially resemble those in the western Indian Ocean, analyses of DNA from tissue samples from one of the Indonesian specimens revealed significant genetic differentiation from the Indian Ocean population. The authors of two studies have suggested that the two populations have been separated for at least several millions of years. The Indonesian form was described as a new species, Latimeria menadoensis, in April , by L.

Pouyard and several Indonesian colleagues. The coelacanth's evolutionary relationships are a matter of controversy. There are several competing hypotheses and many unresolved questions, in large part owing to the many unusual characters found in coelacanths.

Experts largely agree that coelacanths are primitive osteichthyans or bony fishes as opposed to a cartilaginous fishes, such as sharks and rays , and that their closest living relatives are the primitive lungfishes known from freshwaters of South Africa, Australia and South America , but they disagree on the exact placement of the coelacanth in the evolutionary history of vertebrates.

Coelacanths might best be described as occupying a side branch in the basal portion of the vertebrate lineage, closely related to but distinct from the ancestor of tetrapods four-legged vertebrates. Coelacanths are known primarily from the Comoros Islands, which are situated in the Western Indian Ocean between Madagascar and the east coast of Africa, but also live elsewhere along the east African coast and in Indonesian waters. Any physical contact appears to be accidental and non-aggressive.

No pattern has been discerned in cave selection in coelacanths beyond temperature and depth requirements. Individual coelacanths have been observed staying in different caves from night to night, but also will sporadically revisit the same cave over many years. At night, they drift hunt individually.

From the few observations made so far of their feeding, it appears that coelacanths do not pursue prey, but will simply snap up any prey of suitable size which passes within 20 cm of the front of their mouths. During the course of their nightly hunting, coelacanths may range over several kilometers. Because of their specialized fin anatomy, coelacanths possess remarkable agility in the water. They can swim in any direction, and have been witnessed swimming inverted, or in a vertical, face-down posture.

Fricke and Hissmann, ; Fricke, et al. The definitive home range of coelacanths is not known. Individuals tagged with a tracking device have traveled between 2 and 8 km in a day. Fricke and Hissmann, Coelacanths have a rostral organ in their snouts that is believed to have an electroperceptive function.

They also possess color vision that is strongly adapted to a deep water environment. Most visible light at that depth has a wavelength around nm, and the visual pigments of coelacanths are most sensitive to wavelengths of nm and nm, which is a blue shift of roughly 20 nm relative to corresponding orthologous pigments.

Bernis and Hetherington, ; Yokoyama, et al. Coelacanths are opportunistic in their feeding. Some of their known prey species are fish that include: Coranthus polyacanthus , Beryx splendens , Lucigadus ori , and Brotula multibarbata.

Their intracranial joint and associated basicranial muscle likely play an important but unresolved role in feeding. Balon, ; Fricke and Hissmann, Humans are the only known predator of coelacanths. They are considered unfit for eating, and are usually caught by accident by fishermen angling for oilfish Ruvettus pretiosus. The scale color patterns of coelacanths resemble the walls of the caves in the Comoros where they spend their daytime hours and may play a role in crypsis.

Fricke and Hissmann, ; Hissmann, et al. Aside from their role as large predators, nothing is known about the ecosystem role of coelacanths. The L. Their total number is believed to be in the hundreds, and it takes years for a female to reach sexual maturity. The greatest source of coelacanth mortality appears to be as bycatch from gill nets or near-shore, deep water fishing. Fricke discusses black-market trade of coelacanths. He dismisses as rumor the widely reported use of coelacanth oil in eastern medicine for longevity.

However, despite their protected status, Fricke notes that there does exist some low-value, illegal local trade in dead coelacanths, and that the amount private organizations would be willing to pay for a live coelacanth could exceed seven figures. Because the habitat tolerance range of L.

Fricke, ; Plante, et al. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria. Iteroparous animals must, by definition, survive over multiple seasons or periodic condition changes. An aquatic biome consisting of the open ocean, far from land, does not include sea bottom benthic zone.

Balon, E. Grzimek's Animal Life Encyclopedia , Vol. Detroit: Gale. Bernis, W. The rostral organ of Latimeria chalumnae : morphological evidence of an electroreceptive function. Bernstein, P. The ear region of Latimeria chalumnae : functional and evolutionary implications. Zoology , Cupello, C. Brito, M. Herbin, F.