Batfish - Ephippidae | Underwater Asia

Family variety

Most Platax Batfish are relatively similar as adults, but they can vary greatly as juveniles, with each species having its own unique method of camouflage. Due to their shape, they are sometimes referred to as Spadefish.

Size

largest Platax Batfish is the Zebra Batfish (Platax batavianus) which grows to 65cm. The smallest is the Shaded Batfish (Platax pinnatus) at 35cm.

Behaviour

Batfish can be found in groups near open sea locations, often round shipwrecks and buoy lines. Some species are more regularly spotted solitarily or in pairs.

Some Batfish swim on their sides in strong current while others are known to turtles. Juveniles are often shy, sheltering under overhangs and in caves.

Distribution

Platax Batfish are found in all Asian tropical seas.

Habitat

Platax Batfish tend to live on or near coral reefs, forming larger schools to travel across open ocean. They are usually swimming well above the bottom often in pairs or small groups. Juveniles are often solitary, seen sheltering in the reef to avoid predators.

Diet

Batfish feed on algae or plankton, depending on the species.

Reproduction

It is thought that Platax Batfish spawn in the open ocean. Juveniles are pelagic until they reach about 20mm in length, when the juveniles of some species settle on reefs or in lagoons.

Defences

Adults form large tight schools for defence in open ocean. These schools give the appearance of one very large individual, scaring away most potential predators. Juveniles use mimicry as their defence, either camouflage to blend in to their surrounds or mimicking a poisonous or inedible creature.

Threats

Batfish are fished heavily. They are well prized eating fish and are also favourites with the sport fishing industry. Juveniles are very popular in the aquarium trade, but many buyers lack the ability to house them after they grow to full size.

Did You Know?

The latest research suggests that the Shaded Batfish (Platax pinnatus) plays a very important role in keeping the reef free of algae, eating far more algae on reefs damaged by over fishing than traditional algae-eaters such as parrotfish and surgeonfish.

Intro

Batfish are a small family of seven genera the only one found in shallow water is Platax, five species of large round silvery fish.

They are a favourite with divers because of their curious nature, individuals regularly approach divers closely even following them.

They are either solitary, in pairs or a group, sometimes seen in special friendship with a turtle. Juveniles are often boomerang shaped and some species have elaborate markings to mimic something else.

Popular species 1

Tall-fin Batfish

(Platax teira)

One of the most commonly seen Batfish by divers, identified by its steep head profile and the large black blotch by the ventral fin. Juveniles have extremely tall dorsal and anal fins and vertical black bands that usually fade with age.

Popular species 2

Round Batfish

(Platax obicularis)

Large round Batfish with two vertical black bars on their heads. Distinguished from other species by small black speckles on their sides. Juveniles mimic dead leaves floating in the current until they are well into their juvenile stage, seeking out shallow beaches or lagoons when they finally settle.

Popular species 3

Shaded Batfish

(Platax pinnatus)

Much more solitary than any of the other species and very rarely seen in groups. They are more shy than other species and more likely to swim away from divers. They can be identified by their distinctive protruding snout. Juveniles are spectacular - all black with a perfect orange ring around the edge of their fins. They mimic poisonous flatworms to discourage perspective predators.

Popular species

Look out for these species of Batfish on your next scuba dive!

Related Dive Spots

Sipadan

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Gulf of Thailand

FACTFILE

SPECIES: 5

SIZE RANGE: 35-65 cm

DISTRIBUTION:

Platax Batfish are found in all Asian tropical seas.

HABITAT:

On or near coral reefs in pairs or small groups. Juveniles can be seen sheltering in the reef.

THREATS:

Fished heavily. Prized for sport fishing. Juveniles threatened by aquarium trade.

Identification tips

Rounded body with high dorsal and anal fins that get smaller with age in many species. Combination of round body and tall fins give the overall spade shape of these fish.
Short tail fin.
Silvery body with black and sometimes yellow markings.
Juvenile often boomerang shaped mimic leaves, sea grass, flatworms or crinoids.

Batfish - Ephippidae