A new species of pygmy seahorse has been described from South Africa. 

Named Hippocampus nalu, its adult size is less than an inch long and its the first of its kind to be found outside Asia, with its closest known relatives living 5000 miles away.

The name “nalu” is a fitting one as its the local Xhosa and Zulu word for “here it is,” the Hawaiian word for “surging surf,” the wave habitat it was found in, as well as being the middle name of the person who first discovered the species: Savannah Nalu Olivier.

The local dive instructor couldn’t identify the diminutive fish after finding it on one of her dives, sparking a research trip with Seahorse specialists and scientists from around the globe. 

Because they are so tiny and cryptically camouflaged, seven of the eight known pygmy seahorses have only been discovered in the last twenty years. The same team of researchers found and described Hippocampus japapigu in 2018, another pygmy species from Japan, but DNA analysis and CT scans revealed that the two species were very different. 

Drs Louw Claassens and Richard Smith visited Sodwana Bay in search of the new seahorse in October 2018. The reefs of Sodwana Bay are exposed to the powerful swells of the Indian Ocean, very unlike the sheltered coral reefs of Southeast Asia where the other pygmy seahorses are found. A pair of seahorses was finally found along a rocky reef at 15m depth, grasping onto fronds of microscopic algae, amidst raging surge. 

The divers nearly lost the seahorses when a large oceanic swell almost buried them underneath a storm of sand. On one dive, they even found a tiny juvenile measuring just a centimeter in length. Two of these, tail to snout, would only just stretch across a Nickel.

Not for aquariums

The chances of us ever getting to keep this nano seahorse in our aquariums is very slim, however. All Seahorses are vulnerable in the wild from overfishing and habitat loss, and the fear is that other such tiny species could go extinct before we have a chance to discover and protect them. 

Because of their tiny size, they would likely to succumb to filter and pump intakes, be outcompeted by other species and we don’t expect that they would be chowing down on frozen Mysis shrimp any time soon. A constant supply of tiny live food most probably being the order of the day. But to find such a small, delicate species living in such a rough coastal environment, so far away from other reef-dwelling pygmy seahorse species is very cool indeed.

Our thanks to Dr Richard Smith at OceanRealmImages.com for providing the information and giving us permission to use the picture. Image © Richard Smith.