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For the first time, scientists from the National Oceanic and Atmospheric Administration (NOAA) have officially identified a new species of underwater creature based solely on high-definition video footage captured on the ocean floor.
And what an underwater creature it is. Meet Duobrachium sparksae – a strange gelatinous species of ctenophore, encountered by the remote control vehicle (ROV) Deep discoverer while diving off Puerto Rico.
That encounter was in 2015, but when you claim to discover a whole new species – based only on video evidence, by the way, with no physical specimens to help you make your case – it helps with your due diligence.
Duobrachium sparksae. (NOAA)
Fortunately, Deep discovererThe cameras – images of which you can see here – were up to the task, able to capture subtle details on D. sparksaethe body less than a millimeter long.
Subsequent analysis of the organism – now detailed in a new article – indicates that it is easily distinguished from all other known ctenophores species, the researchers say.
“It’s unique because we were able to describe a new species based entirely on high-definition video,” says NOAA marine biologist Allen Collins.
“We don’t have the same microscopes that we would in a lab, but the video can give us enough information to understand the morphology in detail, like the location of their reproductive organs and other aspects.”
These aspects are manifold. From a distance, D. sparksaeThe most notable feature is its bulbous, balloon-shaped body, but it also features two prominent sprawling arms.
In total, three different individuals were filmed by the ROV at depths of around 3,900 meters (nearly 2.5 miles deep), with one of the animals possibly appearing to use its tentacles to anchor itself to the seabed. .
“It was a beautiful and unique organism,” says oceanographer Mike Ford.
“It was moving like a hot air balloon attached to the seabed in two lines, maintaining a specific altitude above the seabed. Whether it was attached to the seabed, we are not sure. We did not observe any attachment. live while diving, but it seems like the organism is touching the seabed. “
The other specimens may not have touched the bottom of the sea, but the three animals were spotted within two meters of it, in an item called the Arecibo Amphitheater, which is in a trench beneath -marine known as the canyon of Guajataca.
It is in these very deep parts of the ocean that ctenophores are found, but the extreme depth of their natural habitat means we don’t come across these mysterious animals very often – let alone new species.
Ctenophores have a number of common names, many of which seem almost comical: comb jellies (named after their “ combs ” of thin eyelashes) are the most popular, but they have also been called gooseberries, sea nuts and Belts of Venus.
Digital illustrations of Duobrachium sparksae. (Nicholas Bezio).
Although animals may superficially resemble jellyfish, they are not closely related. Ctenophores, which are carnivorous, feed on small arthropods and various types of larvae.
Up to about 200 species have been described to date, with about one new species found each year on average, and most finds rely on video capture methods for the basis of physical descriptions, given the difficulties in collecting data. specimens.
“This presents a bit of a conundrum because the taxonomy relies heavily on physical type specimens kept in museums to serve as references against which other materials can be compared,” the researchers explain in their article.
“Indeed, the idea of using photographic evidence to establish new species has been very controversial in recent decades.”
Fortunately, given the high-definition footage the team obtained of these three beautiful specimens of D. sparksae, the researchers claim to have received “no refusals” concerning the discovery of their species.
While the team hopes to collect specimens on future dives for physical analysis, they say it may be decades before they get the chance to fall into the jelly of the comb again.
For D. sparksaeMaybe it’s for the best: Getting a gelatinous drop to sea level, when it normally resides about 4 kilometers below the ocean’s surface, can be a complicated affair.
“Even if we had the equipment, there would have been very little time to process the animal because gelatinous animals don’t store very well,” Collins says.
“Ctenophores are even worse than jellyfish in this regard.”
The results are reported in Plankton and benthos research.
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