Little sea horse, the pygmy seahorse (Hippocampus bargibanti) is almost impossible for divers to distinguish among the gorgonians, mainly due to its small size and very successful camouflage.
- A recently discovered species: seven species of pygmy seahorse are known to date, some endemic. Hippocampus bargibanti was the first to be discovered in 1970. In 2018, an entirely new species was identified in Japan: the size of a grain of rice, Hippocampus japapigu and blends in on algae-covered rocks between 5 and 20 meters deep.
- Little creature: with a maximum size of 2 cm, the pygmy seahorse is one of the smallest seahorse species in the world.
- Camouflage professional: covered with several pink to orange bulbous growths identical to the gorgonians of the Muricella genus to which it clings, it is very difficult for predators to find.
- A gorgonian for life : born dark brown, the pygmy seahorse clings to a Muricella gorgonian during development and adapts its color to it. From then on, it will not leave it.
- It clings to everything it can : the pygmy seahorse moves quite slowly, swimming vertically with rapid oscillations of its dorsal fin. Its prehensile tail grasps various supports or even its partner during reproduction.
- Feeding : don’t be fooled by its small size, the pygmy seahorse is carnivorous and feeds on small crustaceans such as copepods, amphipods, shrimps, and fish larvae. It slowly approaches its prey and sucks it in a blink of an eye with a protractile movement.
- An easy prey : despite its mimicry, its only source of survival, the pygmy seahorse lacks protective scales, bony plates, or any other means of defense, making it easy prey for its natural predators. These are not known with certainty to date, but among them could be toadfish, crabs, or the longnose hawk.
- Reproduction : like all seahorses, the male carries the eggs until hatching. During the breeding season, males and females engage in a nuptial dance in which they entwine using their prehensile tail. This courtship can last an entire day. The expulsion of the young is extremely demanding for the male. According to studies, pygmy seahorses are monogamous, and the couples remain faithful all their lives.
- Remarkable visual acuity : like humans, the eyes of the pygmy seahorse have a fovea, an area of the retina where detailed vision is precise. But the seahorse has an additional advantage, its eyes can move independently of each other.
- A species to protect : since 2001, the pygmy seahorse has been under the new act of « Conservation of Biological Diversity and Protection of the Environment » to prevent its exportation. Unfortunately, the lack of data regarding its habitat and distribution does not allow it to be assigned a status on the IUCN Red List.
Where to meet it? The pygmy seahorse is found in tropical waters of the central Indo-Pacific basin between 16 and 40 meters deep within gorgonians, particularly in the following countries: Indonesia, Philippines, Papua New Guinea, Japan, Great Barrier Reef or also in New Caledonia.
Lisa Ferré
