Indonesian coelacanth | |
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A preserved Latimeria menadoensis, Tokyo Sea Life Park, Japan | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Sarcopterygii |
Class: | Actinistia |
Order: | Coelacanthiformes |
Family: | Latimeriidae |
Genus: | Latimeria |
Species: | L. menadoensis |
Binomial name | |
Latimeria menadoensis | |
L. menadoensis range in violet |
The Indonesian coelacanth (Latimeria menadoensis, Indonesian: raja laut), also called Sulawesi coelacanth, [1] [3] is one of two living species of coelacanth, identifiable by its brown color. It is listed as vulnerable by the IUCN, [1] while the other species, L. chalumnae (West Indian Ocean coelacanth) is listed as critically endangered. [4] Separate populations of the Indonesian coelacanth are found in the waters of north Sulawesi as well as Papua and West Papua.
On September 18, 1997, Arnaz and Mark Erdmann, traveling in Indonesia on their honeymoon, saw a strange fish in a market at Manado Tua, on the island of Sulawesi. [5] Mark Erdmann thought it was a gombessa (Comoro coelacanth), although it was brown, not blue. Erdmann took only a few photographs of the fish before it was sold. After confirming that the discovery was unique, Erdmann returned to Sulawesi in November 1997, interviewing fishermen to look for further examples. [6] [7] In July 1998, a fisherman Om Lameh Sonatham caught a second Indonesian specimen, 1.2 m in length and weighing 29 kg on July 30, 1998, and handed the fish to Erdmann. [8] The fish was barely alive, but it lived for six hours, allowing Erdmann to photographically document its coloration, fin movements and general behavior. The specimen was preserved and donated to the Bogor Zoological Museum, part of the Indonesian Institute of Sciences. [5] Erdmann's discovery was announced in Nature in September 1998. [9]
The fish collected by Erdmann was described in a 1999 issue of Comptes Rendus de l'Académie des sciences Paris by Pouyaud et al. It was given the scientific name Latimeria menadoensis (named after Manado where the specimen was found). [10] The description and its naming were published without the involvement or knowledge of Erdmann, who had been independently conducting research on the specimen at the time. [11] In response to Erdmann's complaints, Pouyaud and two other scientists asserted in a submission to Nature that they had been aware of the new species since 1995, predating the 1997 discovery. However the supplied photographic evidence of the purported earlier specimen, supposedly collected off southwest Java, was recognised as a crude forgery by the editorial team and the claim was never published. [12] [13]
The fish is legally protected through the Minister of Forestry Regulation No. 7/1999. [14] However, it continued to be caught by local fishermen; on November 5, 2014, a fisherman found a specimen in his net, the seventh Indonesian coelacanth found in Indonesian waters since 1998. [15] Eight have been caught as of 2018. [16]
Superficially, the Indonesian coelacanth, known locally as raja laut ("king of the sea"), appears to be the same as those found in the Comoros except that the background coloration of the skin is brownish-gray rather than bluish. It has the same white mottling pattern as the Comorian coelacanth, but with flecks over the dorsal surface of its body and fins that appear golden due to the reflection of light. [9] It may grow to 1.4 meters long. [17] [16]
DNA analysis has shown that the specimen obtained by Erdmann differed genetically from the Comorian population. [18] [19] In 2005, a molecular study estimated the divergence time between the Indonesian and Comorian coelacanth species to be 30–40 mya. The two species show a 4.28% overall difference in their nucleotides. [20]
An analysis of a specimen recovered from Waigeo, West Papua in eastern Indonesia indicates that there may be another lineage of the Indonesian coelacanth, and the two lineages may have diverged 13 million years ago. Whether this new lineage represents a subspecies or a new species has yet to be determined. [21]
Teams of researchers using submersibles have recorded live sightings of the fish in the waters of Manado Tua and the Talise islands off north Sulawesi as well as in the waters of Biak in Papua. [22] [23] [16] These areas share similar steep rocky topography full of caves, which are the habitat of the fish. These coelacanths live in deep waters of around 150 metres or more, at a temperature between 14 and 18 degrees Celsius. [22]
Sulawesi, also known as Celebes, is an island in Indonesia. One of the four Greater Sunda Islands, and the world's 11th-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Archipelago. Within Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger populations.
Coelacanths are an ancient group of lobe-finned fish (Sarcopterygii) in the class Actinistia. As sarcopterygians, they are more closely related to lungfish and tetrapods than to ray-finned fish.
Sarcopterygii — sometimes considered synonymous with Crossopterygii — is a taxon of the bony fish known as the lobe-finned fish or sarcopterygians, characterised by prominent muscular limb buds (lobes) within the fins, which are supported by articulated appendicular skeletons. This is in contrast to the other clade of bony fish, the Actinopterygii, which have only skin-covered bony spines (lepidotrichia) supporting the fins.
A living fossil is an extant taxon that phenotypically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure.
Latimeria is a rare genus of fish which contains the only living species of coelacanth. It includes two extant species: the 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 and tetrapods than to the common ray-finned fishes and cartilaginous fishes.
The rostral organ of the coelacanth or similar in many other fish such as Anchovy is a large gel-filled cavity in the snout, with three pairs of canals to the outside.
The West Indian Ocean coelacanth is a crossopterygian, one of two extant species of coelacanth, a rare order of vertebrates more closely related to lungfish and tetrapods than to the common ray-finned fishes. The other extant species is the Indonesian coelacanth.
The balloon shark is a species of catshark, and part of the family Scyliorhinidae, endemic to the southwestern Indian Ocean off South Africa and Mozambique. Benthic in nature, it is found over sandy and muddy flats at depths of 40–600 m (130–1,970 ft). This thick-bodied species has a broad, flattened head and a short tail; its distinguishing traits include narrow, lobe-like skin flaps in front of the nostrils, and a dorsal color pattern of faint darker saddles on a light grayish background.
Latimeriidae is the only extant family of coelacanths, an ancient lineage of lobe-finned fish. It contains two extant species in the genus Latimeria, found in deep waters off the coasts of southern Africa and east-central Indonesia. In addition, several fossil genera are known from the Mesozoic of Europe, the Middle East, and the southeastern United States, dating back to the Triassic.
Sodwana Bay is a bay in South Africa on the KwaZulu Natal north coast, between St. Lucia and Lake Sibhayi. It is in the Sodwana Bay National Park, and the Maputaland Marine Reserve, and is a popular recreational diving destination. The term is commonly used to refer to both the marine reserve and the terrestrial park, as well as the geographical bay.
Melanotaenia is a genus of rainbowfish from Australia, Indonesia, New Guinea, and nearby smaller islands.
Axelrodichthys is an extinct genus of mawsoniid coelacanth from the Cretaceous of Africa, North and South America, and Europe. Several species are known, the remains of which were discovered in the Lower Cretaceous (Aptian-Albian) of Brazil, North Africa, and possibly Mexico, as well as in the Upper Cretaceous of Morocco (Cenomanian), Madagascar and France. The Axelrodichthys of the Lower Cretaceous frequented both brackish and coastal marine waters while the most recent species lived exclusively in fresh waters. The French specimens are the last known fresh water coelacanths. Most of the species of this genus reached 1 metre to 2 metres in length. Axelrodichthys was named in 1986 by John G. Maisey in honor of the American ichthyologist Herbert R. Axelrod.
Mawsonia is an extinct genus of prehistoric coelacanth fish. It is amongst the largest of all coelacanths, with one quadrate specimen possibly belonging to an individual measuring 5.3 metres in length. It lived in freshwater and brackish environments from the late Jurassic to the mid-Cretaceous of South America, eastern North America, and Africa. Mawsonia was first described by British paleontologist Arthur Smith Woodward in 1907.
Mawsoniidae is an extinct family of prehistoric coelacanth fishes which lived during the Triassic to Cretaceous periods. Members of the family are distinguished from their sister group, the Latimeriidae by the presence of ossified ribs, a coarse rugose texture on the dermatocranium and cheek bones, the absence of the suboperculum and the spiracular, and reduction or loss of the descending process of the supratemporal. Mawsoniids are known from North America, Europe, South America, Africa, Madagascar and Asia. Unlike Latimeriidae, which are exclusively marine, Mawsoniidae were also native to freshwater and brackish environments. Mawsoniids represent among the youngest known coelacanths, with the youngest known remains of the freshwater genus Axelrodichthys from France and an indeterminate marine species from Morocco being from the final stage of the Cretaceous, the Maastrichtian, roughly equivalent in age to the youngest known fossils of latimeriids. Species of Mawsonia and Trachymetopon are known to have exceeded 5 metres in length, making them among the largest known bony fish to have ever existed.
Whiteia is an extinct genus of prehistoric coelacanth fish which lived during the Triassic period. It is named after Errol White.
Trachymetopon is an extinct genus of prehistoric coelacanth from the Jurassic of Europe. Fossils have been found in the Early Jurassic Posidonia Shale of Germany the Middle Jurassic Marnes de Dives of France, and probably the Late Jurassic Kimmeridge Clay of England. Only one species has been named, Trachymetopon liassicum, described by Henning in 1951 from an almost complete specimen found in the Lower Toarcian of Ohmden in Baden-Württemberg. Another specimen is known from the same site, and two older specimens come from the Sinemurian of Holzmaden. The holotype of this species is 1.6 metres in length. A giant specimen of an undetermined species of Trachymetopon found at the Middle Jurassic Falaises des Vaches Noires of Normandy. This specimen, composed of a 53 cm long palatoquadrate, belongs to an individual 4 metres (13 ft) in length. A basisphenoid found in a museum in Switzerland that likely originates from the same locaity probably belonged to an individual around 5 m (16 ft) long, making Trachymetopon the largest of all coelacanths alongside Mawsonia. A study published in 2015 revealed that this coelacanth belongs to the Mawsoniidae. Trachymetopon is one of the few known mawsoniids to have been exclusively marine, while most of the other members of the group have lived in fresh and brackish waters.
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the spine and are supported only by muscles.
Jacques Millot was a French arachnologist, who also made significant contributions in the fields of ichthyology and ethnology.
Serenichthys kowiensis is a fossil species of coelacanth described in 2015 from near Grahamstown in South Africa.
Foreyia is an extinct genus of coelacanth lobe-finned fish which lived during the Middle Triassic period in what is now Canton of Graubünden, Switzerland. It contains a single species F. maxkuhni.