Species Groups

Learn about the following species groups (including their most common members, as well as purchasing, storage and cooking information), or select a specific species from the species list on the right.

More Species Groups 

Ocean Jacket
Nelusetta ayraudi


These distinctive-looking fish are members of the Monacanthidae family, which derives its name from the Greek, meaning ‘one thorn’, referring to the sharp spine on the top of their heads. Some species, especially the males, are brightly coloured and intensely patterned. There are over 100 species in this family, found in tropical and subtropical waters of the Atlantic, Pacific and Indian Oceans. The common name, leatherjacket, comes from their thick, tough, leathery skin, which lacks normal scales and can be peeled off like a jacket. It’s said that the dried skin was once used to polish wooden boats, leading to another common name used overseas, filefish. There are more than 60 species caught around the Australian coast; the most common are:

Ocean Jacket (Nelusetta ayraudi) is by far the most valuable commercial leatherjacket. It has a long, slender pale grey-brown body, often with some reddish blotches, and a relatively small spike. Caught mainly in the Great Australian Bight, it’s available year round and is the largest of the commercial Australian leatherjackets, usually 800g-1.5kg, though it can grow to 3.5kg and 76cm long.

Reef Leatherjackets (Meuschenia species) are a group indigenous to Australia. These brightly coloured and patterned fish with large spikes are caught from southern Queensland south-west to the mid-coast of Western Australia, including around Tasmania, by a small specialist inshore fishery. Four species are commonly marketed under the name reef leatherjacket: Yellowstripe Leatherjacket (Meuschenia flavolineata); Sixspine Leatherjacket (Meuschenia freycineti); Horseshoe Leatherjacket (Meuschenia hippocrepis) and Yellowfin Leatherjacket (Meuschenia trachylepis). They are smaller than ocean jackets, averaging about 600g.

Other leatherjackets occasionally seen in retail shops or harvested recreationally in various parts of Australia include:
Potbelly Leatherjacket (Pseudomonacanthus peroni), found around the north coast of Australia from Byron Bay to Perth, is distinguished by the many small brown spots on its side and the large belly flap that gives it its common name. Unicorn Leatherjacket (Aluterus monoceros), found around most of Australia, from Sydney north west to Perth, has pale skin and a long thin spike which gives it its common name. Bluefin Leatherjacket (Thamnaconus degeni), found around the southeastern coast from Wilsons Promontory (Vic) to the eastern part of the Great Australian Bight, including Tasmania, has distinctive bluish-green fins; males also have bright blue lines on their sides. Velvet Leatherjacket (Meuschenia scaber), is a small reef leatherjacket (averaging about 400g) caught off the southeastern continental shelf. Fanbelly Leatherjacket (Monacanthus chinensis), found around most of Australia except along the south coast from Melbourne to Bunbury, is named for the very large, fan-shaped skin flap on its belly. Tassled Leatherjacket (Chaetodermis penicilligerus) is small with bright green fins and weed-like skin tags that camouflage it among the weedy seabeds it inhabits around most of Australia, from Sydney northwest to Perth. Mosaic Leatherjacket (Eubalichthys mosaicus), found around the southern half of Australia from about Hervey Bay (Qld) to Exmouth (WA), has distinctive bright yellow and blue markings on its side.

Leatherjackets are sold mainly as trunks (headed, gutted and skinned) and occasionally in fillet form (always skinned). In whole fish and trunks look for intact skin (if present), firm flesh, and a pleasant, fresh sea smell. In fillets, look for white to off-white (or pinkish in reef leatherjackets), firm, lustrous, moist flesh without any brown markings or oozing water and with a pleasant fresh sea smell.

Make sure trunks are gutted and cleaned thoroughly. Wrap trunks and fillets in plastic wrap or place in an airtight container. Refrigerate for 2-3 days or freeze for up to 3 months below -18ºC.

Cooking & Serving
Inexpensive leatherjackets are always a bargain. The average yield from whole fish is 30% due to the large, heavy head, but from trunks it’s 65%. Fillets are usually boneless, trunks usually have the backbone left in and can be cooked this way or, if large enough, cut into cutlets; the meat flakes easily away from the large bones. They are related to the highly-prized fugu fish of Japan (without any of the risk of poisoning) and the firm flesh has a mild flavour, low oiliness and is moderately moist. A versatile fish, they are good steamed, poached, pan-fried, stir-fried, deep-fried, baked, braised, grilled, barbecued or smoked. They are a good plate-sized fish cooked whole (head off) and this is the best way to bake or grill them; wrapping in foil or banana leaves helps prevent them drying out. The firm flesh works well in mousseline or minced for fish cakes and fish balls and holds together well in soups, curries and casseroles.