Mud Pipefish, Halicampus grayi Kaup 1856

Widespread in the tropical Indo-west Pacific, from the Gulf of Aden across the Indian Ocean to northern Australia, north to Japan; inhabits silty and muddy soft bottoms on the continental shelf from inshore bays to deep offshore areas to 100 m.

Meristics: D 19-22; A 4; P 15-20; Trunk rings 17-18; Tail rings 32-37.

Head and body: Head length 7.7-10.9 in SL; snout short, length 2.0-2.6 in HL; snout depth 3.3-5.3 in snout length; median dorsal snout ridge with small spines and spinules, discontinuous; lateral snout spines present; eye large, dorsal rim of orbit not strongly elevated; principle body ridges distinct, often with a knob-like protrusion on distal third of trunk rings; spiny or irregularly denticulate on distal half of tail.

Fins: Pectoral fin base protruding laterally.

Brownish with indications of 12-14 diffuse dark bars on side and dorsum of body; often with diffuse dark blotch on side of 12^th-13^th trunk ring; opercle and gill membrane usually with pale bars or blotches.

Preys on small crustaceans.

Reproduction: Ovoviviparous (gives birth to live young). The eggs are brooded by the males in a semi-exposed pouch under the trunk. The pouch folds fall well short of midline of the egg-filled pouch. Males may begin brooding at 103 mm SL.

Eggs: Not described.

Larvae: Morphologically similar to adults at birth, however the snout is relatively long in most planktonic young and shorter in demersal juveniles and adults. Planktonic specimens have been collected in the upper 100 m over depths to at least 2980 m.

None.

Australian Government Legislation: Marine listed under the Environment Protection and Biodiversity Conservation Act 1999.

H. grayi is extremely well camouflaged in muddy or silty habitats.

Halicampus is from the Greek, als, alis for salt and the Greek, kampe meaning bend.

Halicampus grayi Kaup 1856, Cat. Lophobranchiate Fish: 22, India and Australia (as New Holland).

Thompson, Vanessa J. & Dianne J. Bray