Brachaelurus

Brachaelurus is a genus of catsharks in the family Scyliorhinidae. They are commonly known as sleeper sharks, reflecting their tendency to lie on the seabed in a resting state. These sharks are found in the western Pacific Ocean, inhabiting coastal waters and reefs from southern Australia to northern Japan. They are recognized for their distinctive, slender bodies, relatively large pectoral fins, and two dorsal fins with the second situated well behind the first. Their colouration varies, ranging from brown and grey to reddish-brown, often with dark spots or blotches.

Blind shark – Brachaelurus waddi

Characteristics

Brachaelurus species exhibit several defining characteristics:

  • Slender body with a broad, flattened head.
  • Large, rounded pectoral fins, often reaching to or beyond the pelvic fins.
  • Two dorsal fins, with the second placed significantly behind the first.
  • Small, rounded anal fin positioned far back on the body.
  • Short, rounded snout with small, circular nostrils.
  • Widely spaced eyes with a fleshy eyelid.
  • Mouth positioned underneath the snout.

These sharks are typically between 60 and 120 cm long, with some species reaching up to 150 cm. They are generally characterized by a pale brown to grey coloration, often with dark spots or blotches.

Environment

Brachaelurus sharks are primarily found in coastal waters, inhabiting a variety of habitats including rocky reefs, sandy bottoms, and kelp forests. They are often observed resting on the seabed, blending in with the surrounding environment. Their distribution ranges from southern Australia to northern Japan, with various species inhabiting different regions within this range. These sharks are considered to be bottom-dwelling, meaning they spend most of their time on the ocean floor.

Species

The Brachaelurus genus currently encompasses five recognized species:

  • Brachaelurus wadleri (Spotted Sleeper Shark)
  • Brachaelurus colcloughi (Colclough's Sleeper Shark)
  • Brachaelurus japonicus (Japanese Sleeper Shark)
  • Brachaelurus melanobranchus (Blackgill Sleeper Shark)
  • Brachaelurus reticulatus (Reticulate Sleeper Shark)

References

For further information, refer to these reliable sources: