A new species of pygmy seahorse was just officially discovered off the coast of southeastern Japan — and they grow no bigger than a grain of rice.
This colorful creature, known as the Japan pig or Hippocampus japapigu, is between 14 and 16 millimeters tall, and incredibly hard to see with the naked eye.
“That’s equivalent to putting three of them on my pinkie nail,” Graham Short, lead author of a study on the animal published in the journal ZooKeys, told The Dodo. “They look like little Daffy Ducks to me, really cute.”
The seahorse’s lentil-like size has historically helped it escape the notice of both people and predators — until now. The unique little seahorse got its nickname from divers who have been spotting the animal for several years in the waters off southeastern Japan and Hachijo-jima Island, 150 miles south of Tokyo.
“Japanese scuba divers have observed this species of pygmy seahorse for many years, since at least the 1990s, throughout southeast Japan, from the mainland to remote islands off Tokyo,” Short said.
You don’t have to wade too far out to find a Japan pig. Unlike most seahorses, who prefer deeper waters where temperatures do not fluctuate too much, the Japan pig inhabits the shallows, blending in with his environment.
The Japan pig’s colorful array of spots, arranged in what’s been described as a paisley pattern, acts as the perfect camouflage — making the little creature appear to be just another piece of floating seaweed or algae.
“Hippocampus japapigu is really hard to find since it is really small and blends into its environment so well,” Short explained. “The color pattern exhibited by the pygmy seahorse is the exact same color as the rocks and underwater plants it lives on.”
Unlike the six other known species of pygmy seahorses in the the Western Pacific, such as the Hippocampus bargibanti and the Hippocampus pontohi, the Japan pig has a ridge made of triangular bones on his upper back. While its purpose is still unknown, it’s believed that the bump developed through sexual selection, to help the little seahorses attract a mate.
And the personality of the newest addition to the seahorse family is just as adorable as its appearance.
“These pygmy seahorses are really active. They like to swim around each other by hanging onto each other’s tail. They will suddenly dart off only to come back,” Short said. “They remind me of little curious underwater monkeys.”
Seahorse species are suffering globally due to habitat degradation — as well as their use as ornamental souvenirs, in aquarium exhibits and in traditional Chinese medicine. The legal and illegal trade of these unique creatures is threatening populations — with 20 million seahorses estimated to be traded for Chinese medicine each year, and hundreds of thousands captured for aquariums.
Thankfully, the Japan pig has one thing going for him — he’s just too difficult to find.