Platax teira is a marine fish species that can be found in tropical and temperate regions near the shore. It belongs to the order Perciformes, suborder Spinytail, and family Pompanoidae.
The Platax genus consists of five species, with the name deriving from the Greek word "platys," which means "wide" or "flat," referring to the adult fish's broad and laterally flattened body. The juvenile fish have an exaggerated extension of their dorsal and anal fins, resembling a bat with open wings, which inspired the common name in Chinese and English.
The juveniles of the Swallowfish genus display a wide variation in appearance, while the adults are quite similar, with a broad and extremely flat body and symmetrical upper and lower dorsal and anal fins, giving them the appearance of a large disc or shovel.
The first two stripes are located on the eyes, pectoral and abdominal areas, and are narrower, while the third is wider but can be inconspicuous or disappear and is located at the back of the body. The fish can change the shade of their stripes or the whole back of their body quickly, becoming darker to attract cleaning fish to remove insects.
In the wild, swallowfish play a significant role in maintaining the healthy development of coral reefs by cleaning algae. They surpass traditionally recognized herbivorous fish such as parrotfish and spiny tails in terms of algae-feeding species and efficiency. Juvenile swallowfish are too difficult to care for, while adult fish are too large to be mainstream ornamental fish. However, the juveniles' beauty occasionally makes them appear in the aquarium trade.
Platax teira can be found in the Arabian Sea in the Indo-Pacific, from Indonesia to the Sea of Japan. It is mostly found in open water, with a unique appearance, especially juveniles, which can be used as an ornamental fish. Platax teira is the most common species of batfish and can reach a height of about 750px at a body length of 250px, making it a strange-looking fish that easily attracts enthusiasts.
It can be found from Japan in the east to the Arabian Sea in the west, with the Philippines, Malaysia, and the South China Sea being the main fishing areas. Some fisheries in Indonesia can now breed this species in bulk, and these artificial individuals have greatly enriched the trade market. Long bats can grow up to 1125px, and as adults, their dorsal and anal fins gradually retract, eventually turning their bodies into rounded discs.
The sharp-finned swallowfish Platax teira inhabits the coral reefs of bays and lagoons. Juveniles prefer very shallow protected reefs and can sometimes be found inhabiting floating clumps of sargassum at the surface. Juveniles living on shallow reefs usually lie on their sides and hide among various floating objects near the shore. They quickly change their body color to mimic toxic flatworms and sea hares when threatened.
Juveniles living in sargassum tufts use their long, soft dorsal and anal fins to disguise themselves as algae swaying with the current. They are friendly enough to form groups with other juveniles, both of the same and different species, near their living area. They will even approach and interact with divers out of a natural affinity for large cover, pecking at diving suits, hair, etc., if the diver shows no intention of actively approaching or attacking. This friendly disposition is maintained in subadults and adults as well.