Hammerhead Sea Slug

Hammerhead Sea Slug
Chelidonura Varians

Midnight blue gives this unusual sea slug a sleek, almost shadowy presence, broken by electric-blue lines that trace its body from head to tail. Its broad head spreads outward into two unmistakable lobes, while the long, tapering tails trail behind like twin ribbons. Built low to the sand and always moving with purpose, it has the look of a tiny underwater predator designed for hunting rather than hiding.

• Size: Up to around 70 mm
• Range: Tropical Indo-West Pacific; from the Red Sea and East Africa through the Indian Ocean and Southeast Asia to Japan, northern Australia and the western Pacific
• Habitat / Depth: Shallow reef areas, lagoons and reef flats with sandy or muddy bottoms, typically to around 30 m
• Diet: Feeds primarily on flatworms, including acoel flatworms