Marine life  /  Seahorses & pipefish  /  Robust ghost pipefish
Reviewed 2026-09-04
Species entry

Robust ghost pipefish

Solenostomus cyanopterus

Broad-bodied and leaf-like, drifting over seagrass and algae.

Size
To 17 cm
Depth
3–20 m
Habitat
Seagrass and drifting algae
Active
Daylight
Range
Indo-Pacific
Rarity
Lembeh Strait
3 stars of 5, a good week should turn one up
SP-01
robust ghost pipefish · full body · habitat
4:3 · min 2400px

The largest ghost pipefish at 15 to 17 cm, and the most solidly built. The reliable character is the caudal peduncle, which is very short to effectively absent and deepens with age, so the tail fin sits almost directly against the body; in large females it is described as lost altogether. The body is deep, broad and shaped like a leaf or a blade of seagrass, the second dorsal and anal fins are low and transparent, and the skin is essentially smooth — elaborate membranes appear on the snout but not over the body, so it never looks spiky the way the ornate does. Head and body are encased in 25 to 35 star-shaped bony plates. There is a useful marking: two elongate dark spots on the membrane between the first dorsal spines, black and white in a photograph and dark blue in life.

Colour is unreliable and changes — grey, brown, pink, yellow, bright green, reddish or blackish, with individuals reported shifting over a day or so to match new surroundings. The bright green fish hanging in seagrass and the blackish one on a deep reef are the same species. Solitary or in pairs, hovering head-down and ambushing small crustaceans. As in the rest of the family the female broods in a pouch made from her fused pelvic fins, and the young hatch at about 3 mm and go into the plankton. Shallow protected reef, algal flats, seagrass and clear estuaries from the surface to about 28 m, from the Red Sea and East Africa to Fiji.

Where to find:

LocationRarity Best monthsDepthHabitat
Lembeh Strait Indonesia editorial estimate
3 stars of 5, a good week should turn one up
Jul Aug Sep Oct
3–20 m
Seagrass and drifting algae
Dauin & Dumaguete Philippines editorial estimate
3 stars of 5, a good week should turn one up
Year-round
3–20 m
Seagrass

Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.

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