Family: Ephippidae (spadefishes)

Platax orbicularis

The Orbicular batfish inhabits the brackish and marine waters of the Indo-Pacific coral reefs. It is a species with a wide range of occurrence, but may be rare locally. The batfish is characterized by strong lateral compression of the body, a small head and a fine mouth. Its eggs are pelagic, meaning they float in the water, thanks to a drop of fat making them lighter than water. Juveniles occur singly or in small groups in mangrove habitats or sheltered lagoons. During the day, they pretend to be floating leaves that both serve as a source of food and a hiding place. The ventral, dorsal and anal fins are triangular, while the caudal fin is rounded. The body of adult specimens is yellow-silvery with two dark stripes visible, while the body of juveniles is dull orange with fine light dots. Adult specimens appear more frequently in mangrove environments. The maximum body length of the batfish is about 50 cm. This species is characterized by allometric growth, which means an uneven rate of development of body parts. This development is important for the camouflage of individuals at different stages of life. It is valued in China and Polynesia for its delicate meat with an interesting taste. As this species is prone to overfishing, attempts are made to breed it in aquaculture, among others, in French Polynesia and Tahiti, however, these aquaculture suffer from significant mortality due to bacterial contamination.

Rodzina: Osteoglossidae (kostnojęzykowe)

Osteoglossum bicirrhosum (Cuvier, 1829)

Ryba ta występuje w słodkich wodach Ameryki Południowej, a konkretnie w dorzeczach Amazonki, Essequibo i Oyapock. Zasiedla zarówno rzeki białe (o wodach bogatych w substancje mineralne), jak i czarne (z woda o bardzo niskim odczynie pH i dużej zawartości kwasów huminowych i fulwowych). W porze suchej zamieszkuje wolno przemieszczające się lub nieruchome dopływy, rozlewiska i laguny, zaś w porze mokrej przemieszcza się na obszary zalewowe. Ze względu na swoje drapieżne zachowania preferuje płytsze wody. Jest w stanie przystosować się do środowiska o niskim poziomie tlenu rozpuszczonego w wodzie. Używają wówczas swojego pęcherza pławnego jako dodatkowego narządu oddechowego.

Wygląd

Arowana osiąga długość wynoszącą 90 cm, chociaż są doniesienia o osobnikach dorastających do 1,2 m. Maksymalna udokumentowana waga wynosiła 6 kg. Jej wydłużone ciało pokryte jest bardzo dużymi, zdobionymi łuskami, skierowany ku górze pysk jest zwieńczony 2 kolcami, zaś płetwa grzbietowa i odbytowa rozciągają się praktycznie od połowy długości ryby, aż do płetwy ogonowej. Ubarwienie zmienia się wraz z wiekiem ryby. Na ciele osobnika młodocianego widoczne są niebieskie refleksy oraz żółto-pomarańczowy pasek, zaś osobnik dojrzały jest srebrzysty. Cechą charakterystyczną jest jej kościsty język, który jest pomocny w chwytaniu ofiary. Ponadto wiele elementów jamy ustnej zaopatrzonych jest w zęby, w tym szczęka, podniebienie, język oraz gardło.

Odżywianie

Jest to ryba wszystkożerna, która żeruje na powierzchni. Pozycja jej otworu gębowego pozwala jej chwytać zdobycz od dołu. Ma wyjątkowe zachowania drapieżne. Pozostaje blisko brzegu i czeka na przepływającą ofiarę. Zwykle ustawia się bokiem przy powalonym drzewie, wówczas jest mniej widoczna. W trakcie ataku potrafi wyskoczyć ponad powierzchnię wody. To szczególne zachowanie przyniosło jej przydomek „małpy wodnej” lub „ryby małpy”. Pomimo tego, że jej główną dietę stanowią owady, mięczaki, skorupiaki, mniejsze ryby i inne zwierzęta unoszące się na powierzchni wody, w jej żołądku znajdowano również szczątki ptaków, nietoperzy i myszy.

Rozmnażanie

Arowana jest gatunkiem rozdzielnopłciowym z tarłem odbywającym się na początku pory mokrej, czyli w grudniu i styczniu. W ciągu całego sezonu lęgowego samica jest w stanie wyprodukować od 50 do 250 jaj, zaś typowa wielkość pojedynczego lęgu wynosi od 12 do 30. Rola samicy ogranicza się do złożenia jaj. Opiekę nad potomstwem przejmuje samiec, który najpierw jaja, a później larwy i osobniki młodociane przenosi w swoim pysku. Narybek jest zwykle dość duży i już po wylęgu ma długość 50-75 mm. Młode przebywają w pysku samca do momentu wchłonięcia się ich woreczka żółtkowego, czyli około 2 miesięcy. W tym czasie rybacy wyławiają samce, wyjmują młode i przeznaczają je na sprzedaż. W handlu bardzo często dostępne są młode z widocznym woreczkiem żółtkowym.

Znaczenie gospodarcze

Wspólne korzystanie z zasobów populacji arowany srebrnej mieszkańców Brazylii i Kolumbii było przyczyną sporu między władzami w 2005 roku. Kolumbijczycy pozyskiwali młode arowany do sprzedaży jako ryby akwariowe, zaś mieszkańcy brazylijskiej Amazonii łowili dorosłe ryby na pożywienie. Spowodowało to gwałtowny spadek liczebności arowany. Wprowadzono zakazy połowów w Brazylii od 1.09. do 15.11., zaś w Kolumbii od 1.11. a 15.03. Arowana ma dużą wartość gospodarczą dla miejscowej ludności. Stanowi największe źródło białka w porównaniu z innymi rybami amazońskimi. Ponadto, ze względu na niską zawartość tłuszczu, jest uważana za najbardziej strawną i najmniej podatną na choroby. Mieszkańcy Coboclo z Amazonii uważają ją za jedyny dopuszczalny pokarm dla kobiet w okresie połogu. Arowana ma również wielką wartość w branży akwarystycznej, o czym świadczy jej sprzedaż na wielu komercyjnych stronach internetowych oraz ceny jakie osiąga. Jest to jednak najtańszy spośród wszystkich gatunków arowan. Okaz znacznie rzadszej arowany azjatyckiej został sprzedany za 300 tysięcy dolarów. Kostnojęzykowe to jedyna rodzina ryb słodkowodnych, której przedstawiciele żyją po obu stronach Linii Wallace’a, z czterema ważnymi gatunkami w Ameryce Południowej, jednym w Afryce, jednym w Azji Południowo-Wschodniej i dwoma w Australii.

Czy arowana może przetrwać w wodach Polski?

W 2016 roku zaobserwowano pojedynczego przedstawiciela arowany srebrnej w Jeziorze Powsinkowskim. Osobnik ten miał 40 cm długości i był w kiepskiej kondycji. Jego ciało było poranione, najprawdopodobniej po atakach innych ryb. Nie ma szans, aby przetrwał on w zbiornikach słodkowodnych Polski, ze względu na niską temperaturę w nich panującą.

Family: Chaetodontidae (butterflyfish)

In the Chetonidae family, 132 species of fish were distinguished, belonging to 12 different genera, most of them included in the genus Chaetodon. These animals are associated with the tropical waters of the Pacific, Atlantic and Indian Oceans. Some also prefer warm temperate waters. The greatest diversity and abundance of Chetonidae is found in the Indo-West Pacific, from Australia to Taiwan. Only 4 species are found in the eastern waters of the Pacific Ocean and 13 species in the Atlantic Ocean.

Habitat

These fish are closely related to coral reefs. They can also live among seagrass, in deep muddy plains or in shallow lagoons. Juveniles of many species inhabit areas other than mature ones, such as tidal basins, rock reefs, and shallow coral-free areas. Chaetodontidae are most commonly found in shallow waters below 20 meters deep, but some species are seen at depths around 200 meters. Although they are typically marine animals, some are also found in brackish waters of estuaries.

Life

These animals move around the reef very actively during the day and then forage, while at night they hide in crevices and change their coloration to a more subdued one. They usually live in pairs. Fish that eat zooplankton form herds, while juveniles are loners. The body size of the fish varies depending on the species between 9 and 22 cm in length. The largest species, such as the Lined butterfly (Chaetodon lineolatus) and the Saddle butterflyfish (Chaetodon ephippium), can grow up to 30 cm in length. Sources do not provide specific information on the lifespan of these fish. On the basis of information that they reach sexual maturity after one year, it can be concluded that most species live for at least 3 years.

Appearance

The English name of this family “butterflyfish” refers to butterflies, due to brightly colored and patterned bodies of many species, in shades of black, white, blue, red, orange and yellow. Many of them have eyelets on the sides of the body and dark streaks over the eyes, much like the patterns seen on butterfly wings. Their clear coloration can be used for interspecies communication. Although they differ significantly in color, they have some common features. They all have a deep, laterally flattened body. They look almost round from the side. Their dorsal and caudal fins are continuous, emphasizing the oval shape of the fish’s body. The scales covering the body also overlap the dorsal and anal fins. Their pointed snouts are tipped with tiny mouth armed with toothbrush-like teeth. The degree of elongation of the mouth depends on the food consumed. Some species, such as the Forceps butterflyfish (Forcipiger flavissimus), have extra-long tweezers-like jaws that can pick invertebrates from narrow slits. Others, such as the Ornate butterflyfish (Chaetodon ornatissimus), have short jaws for picking live coral polyps. The jaws of some butterflyfishes may account for more than 25% of the body length of a fish.

Feeding

Many species feed on small invertebrates, sponges, fish eggs, thread algae, and others on zooplankton. Some species only feed on coral polyps. Species that feed on algae growing on corals contribute to their protection by removing competing species that take away the light access.

Reproduction

They are dioecious, but there is no obvious sexual dimorphism. They are animals that form monogamous pairs. Most species stay with the same mate for several years, while some species mate for life. Couples accompanied by a juvenile were occasionally observed. This suggests that the young are asexual or capable of maturing into a male or a female, depending on the needs. However, this information has not been confirmed. Based on data collected for several species, it has been found that the spawning season in tropical waters peaks in winter and early spring, while species in temperate areas reproduce in the middle of summer. Some groups reproduce all year round. Spawning usually takes place at dusk. The male swims behind and under the female, poking her with his mouth in a belly filled with eggs. The release of gametes (eggs and sperm) takes place in the water column about 10-15 meters above the bottom. In some species, other males have been seen swimming in a pair during spawning and releasing their sperm. Approximately 28-30 hours after fertilization, a pelagic larva hatches from the egg and hangs upside down just below the water’s surface. This is due to the presence of oil droplets. In their development there is so called tholichthys larval stage, unique among reef fish, in which the animal’s head is covered with ‘armor’ made of thin bone plates that extend beyond the head to form dorsal and abdominal spines. The shape and form of the plates and spikes varies from species to species. All tholischthys larvae are silver in color,  have a deep body flattened laterally. Bone plates are absorbed within a few weeks after the larvae sink to the bottom. The larvae settle during the night and quickly develop into juveniles. In many species, the coloration of juveniles is different from that of adults.

Masking coloration

Butterflyfishes do not take care for their offspring. Due to the small size of the body, they can easily fall prey to predators. Therefore, most species have a band covering the eye and a dark spot, the so-called false eye, located near the tail. These intend to confuse predators that aim for the head but actually attack the back of the fish’s body. Due to their attractive coloration, they are popular as aquarium fish. When selecting the appropriate species, however, it should be remembered that some of them feed on corals and anemones, which is why species that eat zooplankton are more popular.

Butterflyfishes as indicator species

Representatives of the Chetonidae family are considered indicator species that testify to the condition of coral reefs. This is due to the fact that they are bound to this habitat. Of the 5,000 species of fish that live on coral reefs, only 41 of them feed exclusively on corals. The majority, as much as 61%, belongs to the Chaetodontidae family, which is 25 species out of the previously mentioned 41. The dying of reefs contributes to the reduction of the number and diversity of butterflyfishes.

Pennant coralfish Heniochus acuminatus

Butterflyfishes are the most popular tropical fish among divers and aquarists. Among them is the Pennant coralfish belonging to the genus Heniochus, inhabiting the tropical waters of the Indo-Pacific, from East Africa, through South Japan to New Guinea. It inhabits coral reefs and sheltered coastal bays. Mature individuals are usually found in pairs, sometimes forming herds, while juveniles are solitary. The body length of the Pennant coralfish ranges from 15 to 20 cm. It can be distinguished from other representatives of Chetonidae by its elongated back and bony protuberance on the head. The length of the ridge on the back increases as the fish matures. Its oval, laterally flattened body is white with two broad black bands running vertically behind the eye and behind the dorsal process. Yellow dorsal and caudal fins are also characteristic. This fish has a long snout that allows it to reach its main food source in the crevices of coral reefs, i.e. small invertebrates. It also does not despise coral polyps. Juveniles sometimes clear other fish of parasites. Little is known about the reproduction of this species. It produces small, floating pelagic eggs. Hatching time is 18 to 30 hours. The previously described stage of tholichthys is present in their larval development. The larvae remain at this stage for several months and are then planktonic. H. acuminatus is a very beautiful and popular fish, quite easy to care for, which is why it is sold as an aquarium fish.

Class: Anthozoa

Order: Alcyonacea (soft corals)

Alcyonacea are purely marine animals occurring only in the form of polyps. There are approximately 1,290 species of soft corals belonging to 6 suborders and 41 families. Representatives of this order are related to reef-forming (stony) corals, but lack the massive calcified skeleton of calcium carbonate. Instead, they have small limestone sclerites (fine spiky skeletal elements) in their bodies that provide some support and give their flesh a spiky, grainy texture that scares off predators. Several species, incl. blue coral (Heliopora) or pipe coral (Tubipora), have a solid skeleton, seemingly resembling hard corals. Moreover, their polyps always have 8 arms, unlike the stony coral polyps which have 6 or a multiple of 6.

Appearance

Soft corals are one of the most colorful and diverse groups of invertebrates found on coral reefs. They create colonies of various forms, incl. membranous, inlaid, massive, lobed, finger-shaped, woody, fan-shaped, bushy and whip-shaped. In the Caribbean, branching gorgonians and sea fans are the predominant forms of growth, while in the Pacific they are much more diverse, including fleshy corals as well as gorgonians. Although soft coral colonies do not contribute to reef growth, they provide shelter for many reef dwellers. Many animals, such as hydrophilic species, hydrozoans, bryozoans, crinoids, molluscs, crustaceans, and fish, find their shelter among corals, largely only on specific coral colonies. Many species of seahorses look similar to their hosts, thanks to which they perfectly camouflage themselves, eg. Hippocampus bargibanti inhabits only two species of the corals of genus Muricella and Hippocampus denise (fine seahorse) inhabits, i.a., colonies of corals of the genus Muricella, Anella and Echinogorgia.

Longevity

Soft corals include species with different biological characteristics and different ecological requirements. Many species are long-lived with a slow growth rate, while others are fast colonizers with a short life span. Some large colonies of the genus Sinularia (family Alcyoniidae) are probably hundreds of years old. The life expectancy and growth rate of most soft corals is largely unknown as colonies can shrink, due to both biological and physical factors, so there is a poor relationship between colony size and age.

Environment

Most soft corals, unlike stony corals, thrive in nutrient-rich waters with less intense light. Their food consists of small particles caught directly from the water column in the form of phytoplankton, fine particles of detritus, ciliates, flagellates and very small zooplankton. In addition, almost all of them use a symbiotic relationship with photosynthetic zooxanthella (alga) as their primary energy source. In return, the coral provides the algae with nutrients and shelter. This symbiosis depends on the availability of light for photosynthesis. There are taxa that do not bond with algae. Their only food is particles suspended in water, so they are highly dependent on water currents, therefore they occur in habitats with a large flow of water. They can be easily distinguished from those living in symbiosis with algae by their light yellow, orange, red, pink, purple or snow-white color.

Reproduction and colonisation

The dispersal strategies for soft corals vary between species, and include both asexual and sexual reproduction. Rapid colonization of small surfaces of the substrate is mainly related to asexual reproduction. It often involves the formation of stolons, the budding of miniature colonies which then fall off the parent colony and settle nearby, and fragmentation. Larger areas of the bare substrate are usually colonized by settling pelagic larvae formed by sexual reproduction. Then, mature individuals release their gametes into the water column, where fertilization takes place. The resulting pelagic larvae are scattered by currents over long distances. Once they reach the right size, they will settle down to days or weeks after conception. Fertilized eggs of some species remain attached to the mother colony, and the resulting larvae develop on the surface of the colony. After a few days it separates and settles to the bottom near the mother colony.

Diffence strategies

Many species protect themselves from predators, algae or contamination by neighboring organisms by releasing repellants, which are sometimes toxic. Many of these substances have been tested for their bioactivity, and some of them may become useful in the pharmaceutical industry. The main defense products are terpenoid in origin and despite their toxicity to fish, some specialized fish species are able to feed on corals. E.g. corals of the genus Sarcophyton sp. produce toxic sarcophytoxide, which released to aquatic environment causes reduction in the photosynthesis of the algae living in the symbiosis with coral Acropora formosa. Thus, it serves not only as a means of protection against being eaten by predators, but also provides an advantage in competing for living space with other corals. Sarcophytoxide, however, is not an obstacle for the gastropod Ovula ovum, which feeds on those corals and the toxin most probably is metabolised and detoxified in the intestines of the snail. Among the representatives of the gorgonias, such as the species Leptogorgia virgulata, there are substances such as lophotoxin. Their main task is to scare off the fish through stimulating vomits. In addition, they have antimicrobial properties, preventing coral overgrowth. Antarctic corals are protected either exclusively by limestone splinters or by chemicals. Eg., coral Ainigmaptilon antarcticus produces sesquiterpene that prevents starfish from feeding and inhibits development of the bacteria and diatoms. Separate strategy of the chemical defense can be observed in species Plexaura homomalla that produces large quantities of toxic prostaglandines and make the coral flesh untasty for, e.g., fish.

Significance

Soft corals are animals that produce many bioactive compounds with various effects, including antibacterial, antiviral, anticoagulant, antidepressant, antihypertensive, analgesic, anthelmintic, etc. Therefore, they are very commercially important. They are very easy to breed in captivity, much easier than hard corals that are susceptible to infection or damage. Soft corals grow quickly and are easy to divide into new individuals, therefore aquacultured corals are often more durable and cheaper than those imported from nature. Moreover, thanks to such farms it is possible to protect wild reefs. In the past it was believed that soft corals are not able to produce new fundaments for future coral reefs, however, recent discoveries suggest that the colonies of the genus Sinularia have an ability to cement their sclerites and fix them at the base, what makes them reef-building animals.

Toxotes jaculatrix

This species is found in Indo-Pacific waters, from India, through Southeast Asia, Indonesia, Philippines, New Guinea to Australia. It tolerates  changes in salinity, so it can be found in fresh, brackish and salt waters. However, it prefers the brackish waters of the mangrove forests, but also lives in small streams and rivers, as well as near vegetation on coral reefs.

It is a calm fish that lives in small flocks just below or near the surface of the water. If the fish is left without a group, it becomes aggressive towards other fish. The maximum length of the Banded archerfish’s body is 30 cm, however, they usually grow up to 25 cm. In captivity, they reach a smaller body size, about 16 cm and can live from 5 to 8 years, and sometimes even 10. Its body is oblong and raised from the back. The body is generally silver-white, although it may also be yellow. The back is green-olive or brown. The dorsal fin is yellow-green, the caudal fin is earthy green, and the anal fin is silver. On the sides of the body there are wide, black stripes (4 or 5), which shorten as the fish ages. Juveniles have a silver body with a yellow-green or brown back. The archerfish’s eyes are large and set so that he can look forward.

It is omnivorous, the basis of its diet are land insects, molluscs, crustaceans, small fish and plants. Actively hunts its prey by shooting insects on the vegetation above the water surface with a stream of water spewed from the mouth.

It can shoot an insect from a distance of 1.25 meters, and larger specimens are able to hit the victim from a distance of 2-3 meters. It is able to reach the victim within 50 milliseconds after it hits the water. It can also jump above the water and catch an insect on the fly.

It is a dioecious, oviparous animal with external fertilization. The first reproduction occurs when the animal is 10 cm long. During spawning, which takes place in November and December, the female lays between 20,000 and 150,000 eggs, with fertility closely related to the size of the female. They rarely reproduce in captivity. They plays insignificant role in commercial fishing, but are also caught as an aquarium fish.

Indian shooter – sniper fish

The archerfish can see a clear picture despite the different refractive index on the water-air interface. It does this through special adaptations in the eye with an extremely large retina on which the image focuses. This allows the fish to look through the water into the air without having to take into account the distortions in the spatial system, resulting from different refractive indexes, and give an accurate shot. Another possible way how a shooter deals with minimizing refractive indices is to position itself almost directly under its prey before the shot, then it sees the same picture he would see from the air.

The way it shoots its victim is also important, unfortunately it is not known in detail. It is known that a shooter is able to spit water by exerting pressure in the mouth. A stream of water is generated in a tube formed from the tongue hooked on the groove in the palate. Water is thrown out of the mouth by high pressure due to the contraction of the gill chamber. The length of the water stream shot by the fish can reach up to 3 meters.

Family: Chaetodontidae

Chelmon rostratus

This species occurs from the Andaman Sea, through the Indo-Malay region, to Japan and the Great Barrier Reef in the Pacific Ocean. It inhabits coastal reefs, rocky shores and estuaries at depths from 1 to 25 m. The Copperband butterflyfish swims alone or in pairs. Juveniles are loners and inhabit shallow waters. It is an active fish, which swims freely, but also spends time hidden in cracks and crevices where it lies motionless. It is not aggressive, but will defend its territory against other representatives of the genus Chelmon. It reaches small dimensions, the maximum total length is 20 cm, while in captivity it is much smaller. The maximum reported age from the environment was 10 years, while in captivity it lives up to 4 years.

Its body has the shape of a shield with a long protruding muzzle ending with small snout. Its coloration is also characteristic, on the silvery-white body there are 4 vertical stripes in yellow or orange with black and white edges.

At the base of the dorsal fin is a false eye with a bluish-white circle. The dark eye of the fish is much smaller than the false eye.

Young individuals are similar to mature ones, only their false eye is larger in size and the stripes are more intense. It is a carnivore. It uses his long mouth to get food out of the cracks. Its diet is based on polychaetes, representatives of corals such as Aiptasia, molluscs and crustaceans. The Copperband butterflyfish is dioecious and monogamous. During spawning taking place just below the water surface, the female lays eggs, which are fertilized by the male. Fertilized eggs float along with currents in the water column. The larvae lead is planktonic.

Due to its attractive appearance, the pensetnik is a popular aquarium fish. Nevertheless, it is a fish that requires experience, because it is difficult to keep it alive in captivity. Individuals smaller than 14 cm are most often sold, juveniles not exceeding 3 cm in length are very rare. The Copperband butterflyfish is exported from the Philippines, Indonesia and Australia, while individuals caught in Australia are considered more adapted to life in captivity, which is why they achieve a double price. This is due to the methods of obtaining individuals from the natural environment.

Mimicry – a form of defense against predators.

The Copperband butterflyfish due to its small body size can easily fall victim to larger predators. Like other gentle fish, it has developed a false eye to mislead the opponent. The false eye, i.e. a colorful spot located on the dorsal fin, is a form of mimicry, i.e. similar to other dangerous animals. In the Copperband butterflyfish, the false eye, which is much larger than the real eye of the fish, is designed to mislead the predator as to the location of the fish’s head. In most cases, the predator attacks the head so that the victim has no chance of escape. If the predator considers the false eye, and thus the back of the fish’s body, as its head, such a fish has a chance to escape. A similar strategy is used by many species of marine fish, but also freshwater, such as the Oscar.

Rodzina: Callionymidae

Synchiropus splendidus

This species is found in the tropical waters of the Indo-West Pacific, from the Philippines and Eastern Indonesia to Northern Australia. It is a bottom fish associated with coral reefs. He prefers coastal reefs and shallow lagoons with a sandy base, where he settles on sand or rocks, most often among coral branches, where he finds food and shelter. Occurs to a depth of 20 meters. This slow and shy fish is most often found in small groups or in pairs. It reaches a small body size, with a maximum length of 7 cm. Males are slightly larger than females.

The Green spot mandarin is distinguished by its unusual and intense color. The body is light green or olive and is decorated with a combination of black, orange and blue spots. The first ray of the dorsal fin is elongated in the male. The mandarin skin is covered with a thick layer of mucus, which has an unpleasant smell and a bitter taste. Its task is to inhibit many types of parasitic infections and minimize the risk of infection after physical injury. There is also a layer of cells on the skin that produce and release substances with some toxins. It is suspected that this secretion is used as a repellent to predators and other fish. Also, most likely, its bright coloration is supposed to inform predators that it is poisonous. Mandarin feeds during the day. Its diet consists mainly of copepods. In addition, it feeds on algae, plankton and small benthic invertebrates. It is a dioecious fish. Fertilization occurs when the male and female swim close together. Eggs and larvae are pelagic. When the larva reaches the appropriate developmental stage it settles to the bottom. This species breeds successfully in captivity. Due to its attractive coloration, it is a valuable aquarium fish. Fishing for mandarins as aquarium fish plays an important role in the local economies of the Philippines and Indonesia.

The Green spot mandarin – is this an optical illusion like in the case of the Regal blue tang?

The Green spot mandarin is one of two species of vertebrate whose blue color is due to the presence of cyanophores in the skin. Cyanophores are dye cells containing a blue dye. Cyanophores are also present in another representative of the mandarins – Synchiropus splendidus (magnificent mandarin). In other fish, the blue color is structural in nature and is a light phenomenon in which light-reflecting pigment cells (isidophores) participate.