False puffer
Paraluteres prionurus
Fanbelly Leatherjacket
Monacanthus chinensis
About
The fanbelly leatherjacket is an odd-looking filefish that reaches about 38 cm, best known for the large flap of skin that hangs from its belly like a fan.
Also known as: fan-belly leatherjacket, fantail leatherjacket, fanbelly filefish, fanbellied leatherjacket, fan-tailed leatherjacket, fan-bellied leatherjacket, fan-bellied leather-jacket, pigfish
- Length
- 38 cm
- Weight
- max 580 g
- Depth
- up to 50 m
How to tell it apart
Several filefish share this flattened, pointed-snout shape, but the fanbelly leatherjacket stands out by the large, loose flap of skin it can extend from its belly.
Appearance
Its body is flattened side to side, with an upturned, pointed snout and a long, thin filament trailing from its fan-shaped tail. A large flap of skin, or dewlap, hangs beneath its body. The first dorsal fin is a long spine with a shorter spine behind it. Colour shifts with the seabed below: dark over mussel beds, cream or tan over sand, always with irregular darker blotches and streaks. Tiny spines cover the skin, giving it a velvety feel.
Habitat
It lives on reefs, seagrass meadows, and muddy or silty seabeds, as well as in estuaries and weedy rocky coasts, from shallow water down to about 50 m. Its range runs across the Indo-Pacific, from Malaysia and Japan through Indonesia to Australia.
Behaviour
It is active by day and hunts mostly by sight. Alongside grazing on algae and seagrass, it picks off small invertebrates such as amphipods, shrimps, copepods, and worms.
Log it in Into the Blue
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