Famous for their flamboyant, leaflike appendages and mesmerizing movements, sea dragons are aquatic works of art. Since the 19th century, marine biologists had thought that only two types of these enchanting fish existed — the leafy and weedy — until they discovered a third among museum specimens in 2015: the ruby sea dragon.

Now, for the first time, scientists have observed the ruby sea dragon swimming in the wild. It is colored deep red and looks like a stretched-out sea horse with a hump like a camel and a tail it can curl. Unlike its kin, the ruby sea dragon lacks the appendages that help camouflage leafy and weedy sea dragons among the ocean floor’s kelp and sea grass.

Last April, Greg Rouse, a marine biologist at the Scripps Institution of Oceanography in San Diego, and his colleagues embarked on a treasure hunt for the ruby sea dragon in the waters surrounding the Recherche Archipelago in Western Australia. Using a remotely operated underwater vehicle, the team spent several days scouring below for the fish. It wasn’t until the last day of their mission, when the vehicle dove about 175 feet, that they spotted glimmers of red drifting amid the brown sponges and sea plants that dominated the ocean floor.

“It really was a needle in a haystack, and we saw not one but two,” Dr. Rouse said. On Thursday, he and his colleagues published footage they recorded of the ruby sea dragon in the journal Marine Biodiversity Records.

Dr. Rouse and his colleagues figured out that the ruby sea dragon was a new species in 2015 after performing genetic analysis on a dead specimen they received from the Western Australian Museum. The specimen was previously classified by the marine research survey that recovered it as a weedy sea dragon, despite its vibrant red color and lack of appendages, which were thought to have fallen off during the trawling process. During their research, Dr. Rouse and colleagues also found a much older specimen that dated back to 1919.

When they finally recorded the wild ruby sea dragon, they confirmed that the species did not have the camouflage-like appendages. But clearly, it didn’t need them to elude scientists for nearly a century.

(NYT)