KOCHI: An international study led by a team from the Kerala University of Fisheries and Ocean Studies (Kufos), Kochi, has revealed a new species of seahorse in the Indian Ocean. The new species, Hippocampus amandavincentae, has been named after Amanda Vincent, a global authority on seahorses, one of the world’s foremost marine biologists and the founder of Project Seahorse.
The study revealed that the thorny seahorse is not a single species but three. Published on Tuesday in the leading taxonomy journal Zootaxa, the work demonstrates that the thorny seahorse (Hippocampus histrix), historically believed to be widespread from the Red Sea and East Africa across the Indian Ocean to the western Pacific, actually comprises three distinct species.
These findings end more than 150 years of taxonomic confusion and provide an important foundation for future conservation of seahorses.
“Accurate species identification is a crucial first step towards understanding distribution, population status, and developing effective conservation strategies. This discovery reveals the hidden biodiversity in the Indian Ocean and highlights the importance of documenting and protecting its unique species and the critical habitats they depend on,” said Shalu Kannan, the lead author of the paper.
She recently completed a PhD on seahorse conservation from Kufos.
According to Shalu, the specimen for the study was collected from fish bycatch at the Tuticorin fisheries harbour.
“While thorny seahorses are among the most recognisable members of the genus Hippocampus, their outward similarity had masked hidden diversity for more than a century. Using integrative taxonomy and supported by data collected from historic specimens from museums around the world, the authors showed that Hippocampus amandavincentae can easily be distinguished from other spiny seahorses by their snout length, as well as in the number and nature of spines on the coronet, the principal trunk and tail ridges,” she said.
The new species was also separated from its look-alike, the true spiny seahorse Hippocampus histrix, by a genetic distance of 7.0%. Hippocampus amandavincentae is distributed across the Indian Ocean, with confirmed specimens from both the Bay of Bengal and the Laccadive Sea, and additional verified genetic or photographic records from Madagascar, Mozambique and the Seychelles.
The study additionally confirmed that the Jayakar’s seahorse, Hippocampus jayakari, first described in 1900 from the Gulf of Oman, is a valid species of spiny seahorse restricted to the northwestern Indian Ocean.
“Many museum specimens and online biodiversity records of spiny seahorses in the Indian Ocean have been assigned to Hippocampus histrix for decades. Our findings now reveal that these records actually represent multiple species, with practical consequences for global conservation decision-making and policy implementation,” said Rajeev Raghavan, an assistant professor at Kufos and a senior author on this study.
Around seven to nine species of seahorses are known to occur in India’s marine waters, and a trade survey authored by Amanda Vincent in 2021 revealed that around 13 million seahorses were estimated to have been caught in bycatch annually between 2015 and 2017, in the country.
Despite its listing in the WLPA, seahorses continue to be illegally traded, as evidenced by the regular seizures at airports across the country.