Everybody loves a great magician. Under the waves, one doesn’t need to dig too deep to find a bottomless suitcase of them as countless marine creatures are masters at the fascinating game of hide-and-seek.
But there is one animal that truly stands out in this regard and it may come as no surprise to learn that it is a relative of the seahorse: the ornate or harlequin ghost pipefish (family Solenostomidae). This creature’s name is superbly descriptive, for it is gorgeously decorated and yet, this very characteristic allows it to blend into the reef with phantom-like perfection.
The other four members of this family are all skillful camouflage artists, too, whether they’re disguised to resemble seaweed, seagrass, algae, or a sponge. The colouration of these tricksters is highly variable and often dependent on their specific habitat choice, with the image here showing one of the most commonly found forms. Their spiky appearance helps to break up their body outline, allowing them to blend into the background, which is often the highly ciliated tendrils of a featherstar. They will also associate with a wide variety of other hosts such as stinging hydroids, gorgonian fans and black corals.
Until they reach near-adult size of 10 to 15cm, the first part of their lives is spent amongst plankton. Once it is time to grow-up, get a real job and find a husband or wife, they drop down onto a suitable habitat and go from being transparent members of the open ocean to intricately pigmented, glamourous creatures. With limited swimming abilities, it makes sense for ghost pipefishes to put so much effort into their costumes … it could make all the difference between being the predator or the prey.
Unlike the seahorses, where the males take on the responsibility of raising the babies, the female ghost pipefish is the hard-working parent. Divers often encounter this species in their mating pairs or in small groups of around six individuals. A great way to tell male and female apart is by comparing their overall size, as the female can be up to 40 per cent larger than the male. Her pelvic fins may also be enhanced, for they serve as her brood pouch. In fact, her pair of pelvic fins are fused together and the eggs are adhered to specialised skin cells on the inside known as cotylephores. Clutch sizes may be as high as 350 which, once hatched, are set adrift into the plankton. By enduring such a long period in the pelagic phase, this species enjoys the benefits of a wide distribution.
To narrow down where to begin the search for this cool critter, head to any shallow tropical reef, rocky outcrop, or seaweed bed in the Indian or Pacific Ocean.
With a tubular head that accounts for one third of its body length, these pretty pipefishes are well equipped to proficiently pipette their favoured prey of mysid shrimps. And if that isn’t quirky-cool enough, their entire bodies are protected by an armour made of bony plates.
As their species name paradoxus suggests, these delightful denizens are indeed ‘contrary to expectation’, which probably hits the nail on the head as to why they’re loved so much.