Acanthurus triostegus, commonly known as convict tang, manini,convict surgeonfish, convict surgeon, or fiveband surgeonfish, is a species of marine ray-finned fish belonging to the family Acanthuridae which includes the surgeonfishes, unicornfishes and tangs. This species has a wide Indo-Pacific distribution.
Taxonomy
Acanthurus triostegus was first formally described in 1758 as Chaetodon triostegus by Carl Linnaeus, the description being published in the 10 edition of Systema Naturae with its type locality given as "Indies".The genus Acanthurus is one of two genera in the tribe Acanthurini which is one of three tribes in the subfamily Acanthurinae which is one of two subfamilies in the family Acanthuridae.
Etymology
Acanthurus triostegus was given the specific name triostegus which means "three covers", this may refer to the three branchiostegal membranes.
Description
The convict tang is so called because of its bold black stripes on a yellowish background. It is a laterally-compressed oval-shaped fishwith a maximum length of about 26–27 cm (10–11 in). The head is small with a pointed snout and a terminal mouth with thick lips. It has six black stripes which distinguishes it from the zebra tang (Acanthurus polyzona) which has nine, and has a more restricted range in the Indian Ocean. The first black stripe is oblique and passes through the eye. There are two black spots on the caudal peduncle, and on each side there is a sharp, retractable spine, which is used in offence or defence.
Distribution and habitat
Acanthurus triostegus occurs in the tropical Indo-Pacific region. Its range extends from the East African coast and Madagascar to southwestern Japan, Australia and Central America, including many Pacific island groups. It is found over hard bottoms in lagoons, reef slopes, bays and estuaries. Juveniles are common in tide pools, and larger fish are found at depths down to about 90 m (300 ft).
Biology
Acanthurus triostegus frequently feed in the vicinity of freshwater discharges, grazing filamentous algae off the rocks.Typically these tangs graze on filamentous algae growing on coral or rocky substrates. The adults aggregate in large schools to feed and these overwhelm damselfishes attempting to defend their territories. The males and females gather in aggegations to spawn.
Utilisation
Acanthurus triostegus is targeted as a food fish in many parts of its range and in some areas is commercially targeted. In Hawaii it is fished for by recreational anglers and it is also caught for the aquarium trade.
Ctenochaetus tominiensis, the Tomini surgeonfish, Tomini bristletooth, yellowtip bristletooth or orangetip bristletooth, is a species of marine ray-finned fish belonging to the family Acanthuridae which includes the surgeonfishes, unicornfishes and tangs. This fish is found in the western central Pacific Ocean.
Taxonomy
Ctenochaetus tominiensis was first formally described in 1955 by the American ichthyologist John Ernest Randall with its type locality given as Sadaa Island in the Gulf of Tomini, Sulawesi, Indonesia.The genera Ctenochaetus and Acanthurus make up the tribe Acanthurini which is one of three tribes in the subfamily Acanthurinae which is one of two subfamilies in the family Acanthuridae.
Description
Ctenochaetus tominiensis has its dorsal fin supported by 8 spines and 24 or 25 soft rays while the anal fin is supported by 3 spines and 22 or 23 soft rays. The rear ends of the dorsal and anal fins are, uniquely in the genus Ctenochaetus, angular. The lips have warty margins. In juveniles the caudal fin is forked and in adults it is lunate. The maximum published standard length of this fish is 16 cm (6.3 in).The overall colour of the body is yellowish brown with a white caudal fin and broad yellow margins to the dorsal and anal fins.
Distribution and habitat
Ctenochaetus tominiensis is found in the western central Pacific Ocean from Malaysia and Indonesia east through East Timor, the Philippines, Palau, Micronesia, Papua New Guinea, the Solomon Islands, Tuvalu, Vanuatu and Fiji, south to the Great Barrier Reef. It has been recorded from Tonga.This species is found solitarily or in small aggregations on steep drop offs with dense coral growth in inshorse, sheltered waters at depths between 0 and 45 m (0 and 148 ft).
Naso vlamingii, the bignose unicornfish, scibbled unicornfish, Vlaming's unicornfish, and zebra unicornfish, is a species of marine ray-finned fish belonging to the family Acanthuridae, the surgeonfishes, unicornfishes and tangs. This species is found in the Indo-Pacific.
Taxonomy
Naso vlamingii was first formally described as Naseus vlamingii in 1835 by the French zoologist Achille Valenciennes with its type locality given as Molucca Island in Indonesia.[3] This species is classified within the nominate subgenus of the genus Naso.[4] The genus Naso is the only genus in the subfamily Nasinae in the family Acanthuridae.
Etymology
Naso vlamingii has the specific name which honours the Dutch explorer Admiral Cornelis de Vlamingh who collected specimens and drew illustrations of fishes for the Muséum national d’Histoire naturelle and Valenciennes based his description on one of Vlamingh's illustrations.[4]
Description
Naso vlamingii has 6 spines and 26 or 27 soft rays all of similar height supporting the tall dorsal fin and 2 spines and between 27 and 29 soft rays supporting the anal fin. It has a relatively deep body with standard lengths ranging from 2.2, in subadults, to 2.6, in adults, times the body's depth. There is an obvious bulbous protuberance growing from the head above the snout. There are two bony plates on each side of the caudal peduncle and these have keels with anterior pointing spines. The adults develop long filaments from the tips of the caudal fin lobes. The overall colour of the adults is greyish-brown or reddish brown, and they have the ability to change colour quickly, with small dark blue spots on the head and upper flanks. These spots join up to form stripes on the lower flanks. There is a wide blue band running from the eye to the front of the bulbous protuberance. The lips are blue and there is an irregular blue blotch to the rear of the base of the pectoral fin. The caudal fin is blue at its base, grey in the middle with an ill-defined yellow marginand blue outer edges of the lobes and this extends onto the filaments. The intensity of the colour of the blue markings can be increased to a brilliant blue when the fish is displaying in courtship or to communicate with cleaner fish at cleaning stations.This species has a maximum published length of 60 cm (24 in).
Distribution and habitat
Naso vlamingii has a wide Indo-Pacific range which extends from the eastern coast of Africa between Kenya and South Africa, through the Indian Ocean islands, but it is absent the continental southern Asian waters, through the Andaman Sea, Indonesia and into the Pacific. In the Pacific it extends north to southern Japan, east to the Galápagos Islands and south to New Caledonia and Australia.[1] In Australia the species is found at a number of offshore islands and reefs, as well as from the northern Great Barrier Reef south to waters off Sydney in New South Wales and in the waters around Lord Howe Island in the Tasman Sea. The bignose unicornfish is found in deep lagoons and seaward reefs, frequently aggregating in schools that feed on zooplankton around the higher areas of deep slopes and drop-offs.
Biology
Naso vlamingii can live up to 40 years in captivity.[8] Their eggs are fertilized externally after being released in batches by the female. Spawning typically occurs in aggregations, where many individuals come together to release their eggs and sperm simultaneously. They change their feeding pattern throughout their lives. Juveniles are herbivores; feeding mainly with algae, semi-adults are omnivores and adults are primarily carnivores; hunting for zooplankton.
The yellow tang (Zebrasoma flavescens), also known as the lemon sailfin, yellow sailfin tang or somber surgeonfish, is a species of marine ray-finned fish belonging to the family Acanthuridae which includes the surgeonfishes, unicornfishes and tangs. Bright yellow in color, it is one of the most popular marine aquarium fish, though in its natural state, it lives in reefs. The yellow tang spawns around a full moon, eats algae, and has a white barb, located just before the tail fin, to protect itself.
Taxonomy and etymology
The yellow tang was first formally described by English naturalist Edward Turner Bennett as Acanthurus flavescens in 1828 from a collection in the Hawaiian Islands. Zebrasoma refers to the body and the zebra-like stripes or bars on the body of the type species the genus, the sailfin tang (Z. velifer). Its species name is the Latin adjective flavescens, which refers to the tang's yellow color.
Within the genus Zebrasoma the yellow tang forms a species pair with the scopas tang (Z. scopas).[5] The genera Zebrasoma is one of two genera that make up the tribe Zebrasomini within the subfamily Acanthurinae of the family Acanthuridae.
Evolution and genetics
Based on the gene Cytochrome C-oxidase 1 (CO1), a group of researchers was able to reconstruct the phylogenetic tree of the genus Zebrasoma with mitochondrial barcoding sequences.
Description and biology
Adult fish can grow to 20 centimetres (7.9 in) in length, and 1–2 centimetres (0.39–0.79 in) in thickness. Adult males tend to be larger than females. Yellow tangs are bright yellow in color. At night, the yellow coloring fades slightly, and a prominent brownish patch develops in the middle with a horizontal white band. They rapidly regain their bright yellow color during daylight. They can be aggressive, are prone to marine ich, and may damage coral within a reef tank. Male and female yellow tang look very similar. When mating, however, males change color and have a "shimmering" behavior which makes them identifiable.The yellow tang has 5 dorsal spines along with 23–26 dorsal soft rays. The yellow tang also has 3 anal spines as well as 19–22 anal soft rays. There is a white spine on its caudal peduncle that it can use for defense. Its snout is moderately protruding. Its mouth is small with spatulate teeth that are place classed relatively close together inside of the yellow tang's mouth. In juveniles, there are 12 upper and 14 lower teeth. In adults, there are 18 upper and 22 lower teeth.
The yellow tang is a marine fish that lives in reefs and is typically found by itself or in small groups/schools. It is mainly herbivorous and eats filamentous algae.
Reproduction
Spawning happens throughout the year, and it peaks once, normally occurring around the time the moon is full, so this suggests there is some sort of lunar periodicity to the spawning behavior. Spawning happens in pairs or groups, and fertilization is external. Eggs are left in open water and yellow tang are substratum egg scatterers. Yellow tang do not guard their eggs, and once the eggs hatch, the juveniles receive no parental care.
Food
In the wild, yellow tangs feed on benthic turf algae and other marine plant material. In captivity, they are commonly fed meat/fish-based aquarium food, but the long-term health effects of this diet are questionable. However, most experts in the marine aquarium industry express little scepticism that such a well rounded and balanced diet including plant and animal material would be in any way detrimental to mostly herbivorous fishes like tangs since they still need on occasion, complex amino acids and nutrients that only ocean animals can provide. In the wild, yellow tangs provide cleaner services to marine turtles, by removing algal growth from their shells.
Distribution and habitat
It is commonly found in shallow reefs, from 2–46 metres (6.6–150.9 ft) deep, in the Pacific Ocean (Ryukyu, Mariana, Marshall, Marcus, Wake, and Hawaiian islands),[3] west of Hawaii and east of Japan. There have also been reports that they have been found off the coast of Florida in the Western Central Atlantic.[9] A single specimen was filmed in the Mediterranean Sea in spanish waters in 2008, a likely aquarium release.[10] As of July of 2024, yellow tangs have been spotted several times on the shallow reefs of Mexico’s Riviera Maya.
Their habitat is tropical with a temperature range of 24–28 °C (75–82 °F). Hawaii was the most common place for aquarium harvesting, prior to the export ban, where up to 70% of the yellow tangs for the aquarium industry were sourced from. Over 70% of the yellow tang's natural range is protected from collection and fishing. The yellow tang is listed as "Least Concern" by the International Union for Conservation of Nature (IUCN).
Predators and other threats
The yellow tang has many natural predators, including larger fish, sharks, crabs, and octopuses. Another threat is habitat destruction that is caused by humans. Examples of habitat destruction caused by humans are pollution that started on land and flows into the water, physical damage and destruction from harmful fishing practices, as well as overfishing, coral harvesting, and snorkeling, which can potentially cause reef damage.
Conservation status
Conservation status is labelled as least concern, but there are many ways yellow tang are being protected. The most prominent is that yellow tangs are being bred in captivity for aquarium use now more than they were, so collecting yellow tang from the ocean has decreased sharply. This allows wild yellow tang to be able to thrive without too many being taken, so the species is more likely to survive.
In 2010, one study found that fish larvae can drift on ocean currents and reseed fish stocks at a distant location. This finding demonstrated that fish populations can be connected to distant locations through the process of larval drift. They investigated the yellow tang, because larva of this species stay in the general area of the reef in which they first settle. The tropical yellow tang is heavily fished by the aquarium trade. By the late 1990s, their stocks were collapsing. Nine MPAs were established off the coast of Hawaii to protect them. Larval drift has helped them establish themselves in different locations, and the fishery is recovering. "We've clearly shown that fish larvae that were spawned inside marine reserves can drift with currents and replenish fished areas long distances away," said coauthor Mark Hixon.
In the aquarium
The yellow tang is very commonly kept as a saltwater aquarium fish. In 2015, researchers successfully bred them in captivity. Captive-bred yellow tangs are now routinely available for purchase at fish stores and online vendors. They can grow up to 8 inches (20 cm) in the wild, but are introduced to aquariums in the 2-to-4-inch (5.1 to 10.2 cm) range. Some specimens as large as 6 inches (15 cm) are occasionally available. Life expectancy in the wild can exceed 30 years.
Paracanthurus hepatus is a species of Indo-Pacific surgeonfish. A popular fish in marine aquaria, it is the only member of the genus Paracanthurus.
A number of common names are attributed to the species, including regal tang, palette surgeonfish, blue tang , royal blue tang, hippo tang, blue hippo tang, flagtail surgeonfish, Pacific regal blue tang, and blue surgeonfish, hepatus tang, Indo-Pacific blue tang, regal blue surgeonfish, wedge-tailed tang, wedgetail blue tang.
Description
Paracanthurus hepatus has a royal blue body, yellow tail, and black "palette" design. Its length at first sexual maturity is 149.2 mm. Adults typically weigh around 600 g (21 oz) and males are generally larger than females.The back has a broad black area that encloses at the tip of the pectoral, creating a blue oval on each side of the fish that extends in the direction of the eye. The tail has a bright yellow triangle with its apex anterior to the caudal spine and its base at the posterior end of the caudal fin. Black surrounds the triangle on the upper and lower lobes of the caudal fin, in the same hue as the back area.
Paracanthurus has small small scales, each with short ctenii on the upper surface. Scales on the caudal spine possess ctenii approximately three times as long as scales on the rest of the body. Scales anteriorly placed on the head between the eye and the upper jaw are larger with tuberculated, bony plates.
This fish has a compressed, elliptical body shape, and a terminal snout. It has nine dorsal spines, 26–28 dorsal soft rays, three anal spines, and 24–26 anal soft yellow rays, and 16 principal caudal rays with slightly projecting upper and lower lobes. Its pelvic fin is made up of one spine and three rays; this characteristic is considered a synapomorphy of the Naso and Paracanthurus genus. The caudal peduncle has a spine located in a shallow groove, which is also a characteristic of its sister taxa Zebrasoma. It has 22 vertebrae. Paracanthurus has teeth that are small, close-set, denticulated, and described as incisor-like.
Jaw morphology includes an ectopterygoid that links the palatine to the quadrate near the articular condyle. A crest is present on the anterodorsal surface of the hyomandibular. The opercle is less developed, with a distinctly convex profile.
Some slight variation in appearance is present within Paracanthurus. The lower body is yellow in west-central Indian Ocean individuals, and bluish in Pacific individuals . Additionally, the blue color on the trunk of Paracanthurus loses pigmentation in response to changes in light and/or melatonin levels, making its appearance slightly lighter in color at night.
Distribution
The regal blue tang can be found throughout the Indo-Pacific. It is seen in the reefs of the Philippines, Indonesia, Japan, the Great Barrier Reef of Australia, New Caledonia, Samoa, East Africa, and Sri Lanka. A single specimen was photographed in 2015 in the Mediterranean Sea off Israel. Vagrants were found two separate occasions in Hawaii, and are assumed to be aquarium releases.
Paracanthurus is an extant resident in the following territories: American Samoa; Australia; British Indian Ocean Territory; Brunei Darussalam; Christmas Island; Cocos (Keeling) Islands; Comoros; Cook Islands; Disputed Territory (Paracel Is., Spratly Is.); Fiji; French Southern Territories (Mozambique Channel Is.); Guam; India (Nicobar Is., Andaman Is.); Indonesia; Japan; Kenya; Kiribati (Kiribati Line Is., Phoenix Is., Gilbert Is.); Madagascar; Malaysia; Maldives; Marshall Islands; Mauritius; Mayotte; Micronesia, Federated States of ; Myanmar; Nauru; New Caledonia; Niue; Northern Mariana Islands; Palau; Papua New Guinea; Philippines; Réunion; Samoa; Seychelles; Singapore; Solomon Islands; Somalia; South Africa; Sri Lanka; Taiwan, Province of China; Tanzania, United Republic of; Thailand; Timor-Leste; Tokelau; Tonga; Tuvalu; United States (Hawaiian Is.); United States Minor Outlying Islands (US Line Is., Howland-Baker Is.); Vanuatu; Viet Nam; Wallis and Futuna.
Ecolog
Paracanthurus is a diurnal marine species that occupies marine neritic habitats along coastlines. It is found in clear water on exposed outer reef areas or in channels with a moderate or strong current. It primarily utilizes coral reef habitats, but is also known to utilize seagrass beds, mangroves, algal beds, and rocky reefs [1]. It has an upper and lower depth limit of 2 meters and 40 meters, respectively .They live in pairs or small groups of 8 to 14 individuals. They can also be found near cauliflower corals on the seaweed side of coral reefs. Juveniles can be found in schools using Acropora for shelter. Numbers of males and females tend to maintain a 1:1 ratio.
The fish is important for coral health as it eats algae that may otherwise choke it by overgrowth.
Diet
As a juvenile, its diet consists primarily of plankton. Adults are omnivorous and feed on zooplankton, but will also graze on filamentous algae.[16]
Life cycle
Spawning takes place year round, with a peak between April and September. Spawning occurs during late afternoon and evening hours around outer reef slopes. This event is indicated by a change in color from a uniform dark blue to a pale blue. Males aggressively court female members of the school, leading to a quick upward spawning rush toward the surface of the water during which eggs and sperm are released. The eggs are small, approximately 0.8 millimetres (1⁄32 in) in diameter. The eggs are pelagic, each containing a single droplet of oil for flotation. The fertilized eggs hatch in twenty-four hours, revealing small, translucent larvae with silvery abdomens and rudimentary caudal spines. Once opaque, the black "palette" pattern on juveniles do not fully connect until mature. These fish reach sexual maturity at 9–12 months of age, and at approximately 149.22 mm in size.[6] Fecundity has a tendency to positively correlate with weight.
Fishes in the family Acanthuridae, including Paracanthurus, produce altricial larvae that receive no v. parental care. After hatching, these larvae rely on yolk reserves in order to survive their first two to three days of life.
Importance to humans
The regal blue tang is of minor commercial fisheries importance; however, it is a bait fish. The flesh has a strong odor and is not highly prized. This fish may cause ciguatera poisoning if consumed by humans. However, regal blue tangs are collected commercially for the aquarium trade. Handling the tang risks the chances of being badly cut by the caudal spine. These spines, one on each of the two sides of the caudal peduncle, the area where the tail joins the rest of the body, are extended when the fish is stressed. The quick, thrashing sideways motion of the tail can produce deep wounds that result in swelling and discoloration, posing a risk of infection. It is believed that some species of Acanthurus have venom glands while others do not. The spines are used only as a method of protection against aggressors.
The regal blue tang is one of the most common and most popular marine aquarium fish all over the world, holding its place as the 8th most traded species worldwide. In 1997–2002, 74,557 individuals were traded in official tracked sales and in 2011 approximately 95,000 Paracanthurus were imported for use as a marine ornamental fish. When harvesting Paracanthurus in the wild, juveniles are specifically targeted since they are easiest to collect due to their tendency to travel in schools. Paracanthurus for human use are harvested in the wild rather than raised in aquaculture. Conservationists encourage efforts to switch to aquaculture in order to better preserve wild populations.
