Sharptail mola | |
---|---|
Mounted specimen at the Museu Nacional de Historia Natural de Lisboa | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Tetraodontiformes |
Family: | Molidae |
Genus: | Masturus T. N. Gill, 1884 |
Species: | M. lanceolatus |
Binomial name | |
Masturus lanceolatus (É. Liénard, 1840) | |
Synonyms | |
Orthagoriscus lanceolatusLiénard, 1840 Contents |
The sharptail mola (Masturus lanceolatus) is a species of mola found circumglobally in tropical and temperate waters. It is similar in appearance to the ocean sunfish (Mola mola), but can be distinguished by the projection on its clavus (pseudo-tail). Other common names include sharpfin sunfish, point-tailed sunfish, and trunkfish. [2] [3] Rarely encountered, very little is known of the biology or life history of the sharptail mola. It has recently become important to commercial fisheries operating off eastern Taiwan. [4] This species is the only member of its genus. [5]
The distribution of the sharptail mola is worldwide in tropical and temperate waters. [2] They are primarily inhabitants of the epipelagic zone, but are rarely sighted at the surface, with many of those appearing to be ill and parasite-ridden. During the day, they spend most of their time at depths of 5–200 m (16–656 ft), preferring water temperatures above 20 °C, but making repeated dives into cooler, deeper water, possibly to feed or to avoid predators. At night, they spend most of their time between 100 and 250 m (330 and 820 ft). They have been sighted in the mesopelagic zone to a depth of 670 m (2,200 ft), but may descend to over 1,000 m (3,300 ft). One tagged individual in the Gulf of Mexico moved an average of 10 km (6.2 mi) a day. [6] [7]
One of the largest bony fishes, the sharptail mola can measure up to 3.4 m (11 ft) long and weigh 2,000 kg (4,400 lb). [2] It has an oval body with an evenly convex forehead profile. The eyes are placed more forward on the head than in the genus Mola. The teeth in both jaws are fused into beak-like plates. The dorsal and anal fins are placed posteriorly, and the base of the dorsal fin is longer than that of the anal fin. In place of a caudal fin, the dorsal and anal fins merge into a clavus, formed by 18-20 fin rays. The central rays in the clavus are supported by the last vertebra and form an elongated triangular lobe; some authors believe these rays to be remnants of the larval caudal fin, though this is disputed. [3] [8] [9]
Their skin is covered with small dermal denticles that are finer than those of the ocean sunfish. Their coloration is silvery with the upper parts of the sides grayish brown to blackish. The sides may bear ill-defined dark spots. The dorsal and anal fins are slate gray, while the clavus may have pale blotches. [10] This species is distinguished from the similar Masturus oxyuropterus by its prominent chin, the lack of a concavity above the eyes, and the unequal lengths of the dorsal and anal fin bases. These two forms may represent different sexes of the same species. [9]
Robert Collett, who examined some of the first known specimens of sharptail mola, speculated they might represent abnormal ocean sunfishes that had retained larval characteristics. However, the caudal projection is now known to be a secondary development that follows the loss of the primary tail. [11] The swimming mode of the sharptail is similar to that of other ocean sunfishes, using sculling motions of its long dorsal and anal fins to propel itself through the water. The anal fin moves more extensively than the dorsal fin. The small pectoral fins move constantly to control pitch, while the clavus is employed as a rudder. [6]
Juvenile sharptail molas are known to feed on benthic annelids and sponges. Adults likely feed on medusae, siphonophores, ctenophores, and salps, as well as some fishes, crustaceans, and molluscs. [6] Sharptail molas sometimes have remoras attached to the surface of their bodies or inside their buccal cavities. In 1949, a sharptail mola off North Carolina was found with a common remora (Remora remora) wedged inside the gill arches on its right side. This evidently impaired the respiration of the mola, such that it foundered on the beach and was collected by fishermen. [12]
Molas are oviparous and are amongst the most fecund of all fishes. Larval sharptail molas are rounded in shape and develop large pyramidal dermal spines over their bodies, which persist through a prejuvenile phase called the "Molacanthus" stage. In this stage, the body is deep and compressed, with a thin, keel-like structure below the abdominal region. This ridge is made from skin and covered with several rows of small spines. The skin is rough, being covered with small prickles. The spines eventually diminish in size and disappear, leaving scars obvious on the sides of young fish up to 70 mm (2.8 in) long. Their coloration is dark brown on the back, becoming very light on the sides and belly. [13] [14] The lifespan for this species is estimated to be 85 years for males and 105 years for females. [4]
Since 2002, promotion of an ocean sunfish festival in Hualien County, Taiwan, has increased demand for the meat of the sunfish (called "mambo fish" after a public vote), whereas before only the intestines and reproductive organs were sold while the rest of the fish was discarded. The month-long April festival draws some 120,000 visitors, and features "101 ways to eat" sunfish. Consequently, catches of sunfishes off eastern Taiwan have risen sharply, with the sharptail mola comprising 90% of the catch. In 2005, 208 tonnes were landed and the annual sunfish catch was valued at US$ one million. The species is caught by set net, drift net, and longline fisheries. The impact of this increased exploitation on sunfish stocks is under investigation. [4] [15]
On Wednesday 30 November 2022, the carcass of a 450-pound Sharptail mola was found ashore on a beach in North Carolina. It was kept by the North Carolina Museum of Natural Sciences. [16]
The ocean sunfish, also known as the common mola, is one of the largest bony fish in the world. It is the type species of the genus Mola, and one of five extant species in the family Molidae. It was once misidentified as the heaviest bony fish, which was actually a different and closely related species of sunfish, Mola alexandrini. Adults typically weigh between 247 and 1,000 kg. It is native to tropical and temperate waters around the world. It resembles a fish head without a tail, and its main body is flattened laterally. Sunfish can be as tall as they are long when their dorsal and ventral fins are extended.
The mud sunfish is a freshwater ray-finned fish, a sunfish from the family Centrarchidae, which widely distributed in the fresh waters along the Atlantic coast of North America, ranging from New York to Alabama. It is the only species in the genus Acantharchus.
The Molidae comprise the family of the molas or ocean sunfishes, unusual fish whose bodies come to an end just behind the dorsal and anal fins, giving them a "half-fish" appearance. They are also the largest of the ray-finned bony fish, with the southern sunfish, Mola alexandrini, recorded at 4.6 m (15 ft) in length and 2,744 kg (6,049 lb) in weight.
Ridgeheads, also known as bigscales, are a family of small, deep-sea stephanoberyciform fish. The family contains approximately 37 species in five genera; their distribution is worldwide, but ridgeheads are absent from the Arctic Ocean and Mediterranean Sea. Although the family is one of the most widespread and plentiful of deep-sea families, none of its members are of interest to commercial fishery.
The gag grouper, also known as velvet rockfish, the gag, or charcoal belly, is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. It comes from warmer parts of the West Atlantic, including the Caribbean and Gulf of Mexico. It is a drab, mottled-gray fish lacking the distinguishing features of most other groupers. Its pattern of markings resemble the box-shaped spots of the black grouper. It lacks the streamer-points on the tail fin that scamp and yellowmouth grouper have and lacks yellow coloration around the mouth.
The slender suckerfish or lousefish is a rare species of remora found around the world in tropical and subtropical seas, in areas like the Atlantic, Pacific, and Indian Ocean, from depths from 1 to 100 meters deep.
The spearfish remora is a species of remora with a worldwide distribution in tropical and subtropical seas. Remoras attach themselves to other fish with a sucker on the head and this fish is almost exclusively found living on billfishes or swordfishes, and sometimes on sharks.
The smalleye pygmy shark is a little-known species of squaliform shark in the family Dalatiidae, found in water 150–2,000 m (490–6,560 ft) deep near Japan, the Philippines, and Australia. It migrates vertically daily, spending the day in deep water and the night in shallower water. One of the smallest shark species, the smalleye pygmy shark is known to reach only 22 cm (8.7 in) long. It has a blackish, spindle-shaped body with relatively small eyes, and a spine preceding the first dorsal fin, but not the second. Bioluminescent photophores occur on its underside, which may serve to disguise its silhouette from predators. This species feeds on small squid, krill, shrimp, and bony fishes. It is aplacental viviparous. The International Union for Conservation of Nature has assessed it as Least Concern, citing its wide distribution and lack of threat from fisheries.
The spined pygmy shark is a species of squaliform shark in the family Dalatiidae found widely in all oceans. Growing no larger than roughly 28 cm (11 in), it is one of the smallest sharks alive, with this record beaten by the dwarf lanternshark. This shark has a slender, cigar-shaped body with a sizable conical snout, a long but low second dorsal fin, and an almost symmetrical caudal fin. Its sister species S. aliae and it are the only sharks with a spine on the first dorsal fin and not the second. Spined pygmy sharks are dark brown to black, with numerous bioluminescent organs called photophores on their ventral surface. The shark is believed to use these photophores to match ambient light conditions, which break up its silhouette and help the shark to avoid being seen by predators below.
The blurred lanternshark is a little-known species of dogfish shark in the family Etmopteridae, found around the world in benthic and pelagic habitats from a depth of 110 m (360 ft) to over 1 km (0.62 mi) down. This shark forms the E. pusillus species group with the smooth lanternshark, which are distinguished from other members of its family by having irregularly arranged, flat-topped dermal denticles that give them a "smooth" appearance. Both species are slender-bodied with long heads, two dorsal fins bearing spines, no anal fins, and light-emitting photophores. The blurred lanternshark is larger, reaching 67 cm (26 in) or more in length. This species feeds on small squid, fishes, and fish eggs, and is ovoviviparous. It has been assessed as of Least Concern by the International Union for Conservation of Nature, because of its wide distribution and lack of threat from fishing pressure.
Springer's sawtail catshark is a species of shark belonging to the family Pentanchidae, the deepwater catsharks. This shark is found in waters 457–699 m (1,499–2,293 ft) deep off the islands of the Antilles, from Cuba to the Leewards. A small, slim-bodied species reaching a length of 48 cm (19 in), the Springer's sawtail catshark can be identified by its color pattern of horizontal dark stripes in front of the first dorsal fin, and dark dorsal saddles behind. It is additionally characterized by the presence of saw-toothed crests, made of enlarged dermal denticles along both the dorsal and the ventral edges of the caudal fin. The Springer's sawtail catshark is oviparous.
A sunfish, also called a mola, is any fish in the genus Mola. The fish develop their truncated, bullet-like shape because the back fin, which is present at birth, never grows. Instead, it folds into itself as the creature matures, creating a rounded rudder called a clavus. Mola in Latin means "millstone" and describes the ocean sunfish's somewhat circular shape. They are a silvery color and have a rough skin texture.
The longfin trevally, also known as the longfin kingfish, longfin cavalla or armed trevally, is a species of inshore marine fish in the jack family, Carangidae. The species is common in tropical to subtropical waters of the Indo-Pacific, ranging from South Africa in the west to Japan in the east, typically inhabiting inshore reefs and bays. The species is easily distinguished by its elongate dorsal and anal fin lobes and filamentous dorsal rays, as well as its scaleless breast. Longfin trevally are pelagic predators, taking a variety of small fish, cephalopods and crustaceans, and reach sexual maturity at around 21 cm. The species has a maximum known length of 57 cm and weight of 3.5 kg. The longfin trevally has a very complex taxonomic history which is closely intertwined with another currently valid species, Carangoides ciliarius, which may yet prove to be synonymous. Longfin trevally are of minor importance to fisheries throughout their range and are considered good table fish, and are occasionally taken by anglers.
Zebrasoma xanthurum, the purple tang or yellowtail tang, is a species of marine ray-finned fish belonging to the family Acanthuridae which includes the surgeonfishes, unicornfishes and tangs. This species is endemic to the north western Indian Ocean.
The popeye catalufa, also known as the bigeye soldierfish, is a species of marine ray-finned fish in the family Priacanthidae, the bigeyes. This fish has an overall dusky orange to red colour with white markings. The dorsal fin appears feathery while rest of fins have black margins. It occurs in the eastern Pacific, where it is found from Oregon to Chile. It occasionally makes its way into the aquarium trade. It grows to a size of 34 centimetres (13 in) in length. This species is nocturnal and shy, preferring deeper waters off islands. It has been recorded associating with squirrelfishes and cardinalfishes but the popeye catalufa goes as deep as 76 metres (249 ft), deeper than its associated species. This species has been recorded from rocky habitats at depths of less than 5 metres (16 ft) to over 100 metres (330 ft). It is a carnivorous species and, when kept in captivity, is known to feed on worms, crustaceans and brittle stars.
Histiophryne is a genus of marine ray-finned fishes belonging to the subfamily Histiophryninae in the family Antennariidae, the frogfishes. These fishes are found in waters ranging from Taiwan to South Australia. There are currently five known species. These fishes are easily distinguished from other anglerfishes as having a reduced luring appendage, a highly evolved form of the first dorsal fin spine.
The giant sunfish or bumphead sunfish, , is a fish belonging to the family Molidae. It is closely related to the more widely known Mola mola, and is found in the Southern Hemisphere. With a specimen found dead near the Azores in 2021 weighing in at 2744 kg it is the largest extant bony fish species in terms of maximum recorded mass by a wide margin. It can be found basking on its side occasionally near the surface, which is thought to be used to re-heat itself after diving in cold water for prey, recharge its oxygen stores, and attract gulls to free itself of parasites.
Tripodichthys is a genus of marine ray-finned fish belonging to the family Triacanthidae, the triplespines or tripodfishes. The three species in this genus are found in the Indian Ocean and the western Pacific Ocean in shallow water over soft substrates.
The lesser gurnard, or Quekket's gurnard, is a species of marine ray-finned fish belonging to the family Triglidae, the gurnards and sea robins. This species is found in the southwestern Indian Ocean and marginally in the southeastern Atlantic Ocean. This species is of commercial importance as a food fish.
Jeboehlkia is a monotypic genus of marine ray-finned fish, related to the groupers and classified within the subfamily Epinephelinae of the family Serranidae. It is a species of relatively deep water which is found in the western Atlantic Ocean. The only species in the genus is Jeboehlkia gladifer, the bladefin bass.
{{cite journal}}
: CS1 maint: multiple names: authors list (link){{cite journal}}
: CS1 maint: multiple names: authors list (link){{cite journal}}
: CS1 maint: multiple names: authors list (link)