A recent study published in Frontiers of Biogeography has revealed surprising findings about zoantharian hexacorals, challenging the widely held belief that the Atlantic and Indo-Pacific oceans are vastly different in terms of marine life. Led by dr.Maria “Duda” Santos from the UH Mānoa Hawaiʻi Institute of Marine Biology (HIMB) ToBo Lab and the University of the Ryukyus, this research sheds light on the genetic and morphological similarities between zoantharians from these two distant regions.
Guest blog post by Dr.Maria “Duda” Santos and Maria Frostic
In marine biogeography, it is commonly believed that diving in Brazil would reveal a completely different set of fish and coral compared to diving in okinawa. However, during a dive in okinawa, Dr. santos experienced a moment of déjà vu when she came across zoantharians that looked exactly like those found back home in Brazil – same colors, shapes, and sizes.

“During my first dive in Okinawa, I was surrounded by a multitude of species I had never seen in my homeland of Brazil.But then I saw the zoantharians. they looked exactly like the ones back home-the same colors, shapes, and sizes. It was striking.”
shares Dr. Santos
The study found that despite the vast distance between these two regions and their typically high levels of species diversity, zoantharians show surprisingly narrow genetic and morphological differences.
the Secrets of the Ultimate Travelers
The researchers suggest that this may be due to zoantharians’ ability to travel long distances through an “epic” larval phase and hitchhiking on floating objects across ocean basins.
Furthermore, their slow evolutionary rate keeps distant populations looking similar even after millions of years of separation by continental barriers.
This discovery has significant implications for our oceans’ future as climate change continues to impact conventional stony corals, allowing zoantharians to take over reef habitats.
A Global Atlas for a Changing Oceann
This groundbreaking study involved a team effort from researchers in hawai’i,Okinawa,Russia,Brazil,Hong Kong,Taiwan,and Indonesia. By combining DNA data and records from Mexico to the Philippines, the team has created the first-ever global “atlas” for zoantharians, providing a vital baseline for monitoring how marine life will adapt to a warming world.
Original source
Santos, M.E.A., Kise, H.,Fourreau,C.J.L., Kiriukhin, B., Kitahara, M.V., Baker, D.M., Toonen, R.J., Liu, P.J., Chang, A., Tu, T.-H., Widiastuti,
Agustini,K.M.P. Bowen,B.W.andReimer,J.D.(2026).GlobalbiogeographyofzoanthariansindicatesaweakgeneticdifferentiationbetweentheAtlanticandIndo-Pacificoceans,anddistinctcommunitiesintropicalandtemperateprovinces.Frontiers of Biogeography,19.doi:https://doi.org/10.21425/fob.19.174247
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This landmark study provides valuable insights into the behavior and evolution of zoantharians and their role in shaping our oceans’ future.


This research is absolutely fascinating!