Sentosa means “peaceful” in Malay. This is the name given to an island in Singapore that is particularly popular with tourists, where a new species of particularly deadly jellyfish has just been discovered. The old name of this piece of land, Pulau Blakang Mati until 1972, meaning “island of death from behind”, seemed more appropriate. The researchers were not mistaken, choosing the name of Chironex blakangmati for this new creature.
To be exact, it is in fact one of the four known species of box jellyfish – also called box jellyfish – and whose umbrella is more cubic than classic jellyfish. Researchers believe that they are the most dangerous marine animal for humans. Their stings, transmitted by special cells called nematocysts and located on their tentacles, are powerful enough to kill a person and that’s not all: the critter would be able to spot prey and swim towards it.
The subfamily of Chironexlike the C. blakangmatiswims, actively identifies and pursues its prey thanks to substantial musculature and complex eyes. Previously, scientists believed that C. blakangmati belonged to the species of C. yamaguchii, but a new study, published in the Raffles Bulletin of Zoology and relayed by Live Science, demonstrates that they are in fact two different species.
“THE Chironex blakangmati are very similar to the C. yamaguchii –a species that I myself discovered during my master’s degree in Okinawa”says study co-author Cheryl Ames, professor of marine biology at Tohoku University in Japan and associate at the Smithsonian Institution in Washington, in a press release. “But we realized that they do indeed belong to two completely distinct species. I even went to dust off an old copy of C. yamaguchii which I still owned in Okinawa to make the comparison!”
Box jellyfish that are still very little known
The genetic and morphological differences between the two animals allow us to conclude that the Chironex blakangmati is a species in its own right, summarizes the press release: “Our comprehensive analysis of all species of Chironex known to date tells us a lot about these box jellyfish, writes Danwei Huang of the University of Singapore. We also propose a new method which could be useful to other researchers to distinguish species.
The study also reveals, for the first time, that Chironex indrasaksajiaeanother of four species of box jellyfish thought to be endemic to Thailand, now also swims in Singaporean waters. What we call the Thai “sea wasp” can also be deadly. “We were surprised to find it so far from the Thai coastsays Cheryl Ames. Identifying range extensions like this is really important. We currently know very little about the biodiversity and spatial distribution of box jellyfish.”
Researchers from Tohoku and Singapore Universities, who made the discovery, explain that a better understanding of the distribution of box jellyfish could help us better prevent the injuries and deaths they cause. Between forty and one hundred people die each year from their bites – far more than from shark attacks. A figure which could be strongly underestimated, according to certain specialists. Angel Yanagihara, a biochemist at the University of Hawaii, blames box jellyfish for 500 deaths a year in the Philippines alone.
