We thought the world contained only two sea dragon species, but then scientists identified a third in 2015 — a fiery red one. Using specimens that dated back to 1919, they deemed it the ruby sea dragon (Phyllopteryx dewysea) for its bright colorization. Now, we have our first look at the rare sea dragon in the waters of Western Australia, its natural habitat.
Fighting poor weather, researchers deployed a miniature remotely operated vehicle (miniROV) for four, 1-hour dives on April 7, 2016, to find, as researcher Josefin Stiller describes the sea dragon, "the red needle in the haystack."
Luck was with Stiller and her team as they were able to record the ruby sea dragon in its deep-sea habitat, a first for the species. The video will provide researchers with much needed information about the creature's anatomy and behavior, the latter of which was observed by the miniROV when it caught a sea dragon eating.
This is a ruby sea dragon that washed up on the Point Culver cliffs in Western Australia. In addition to its red color, the sea dragon's curled and yellow-tipped tail set it apart from other sea dragons. (Photo: Zoe Della Vedova)
There are two other sea dragon species, the swimming-branch-looking leafy sea dragon (Phycodurus eques) and the common se adragon (Phyllopteryx taeniolatus), and both are found in the waters of Australia and in aquariums. The ruby sea dragon differs from its cousins in a few ways. First, it lacks the common sea drgon's spinier appendages and the leafy sea dragon's leaf-like appendages. Second, the ruby sea dragon's tail curls and is tipped with yellow, traits not found in either of its cousins. And third is that the ruby sea dragon has a unique, eye-catching color.
Stiller's study posits that these differences complicate some evolutionary aspects of the species, particularly the prehensile tails, which Stiller theorizes are used for clinging to surfaces during high-surge waters. Given the ruby seahorse's deep-water living (another difference from its cousins), Stiller proposes that lack of appendages, used for camouflage by the leafy and common sea dragons, helps to reduce drag while the ruby sea dragon swims through the currents. As for its red color, Stiller suggests that this feature is the camouflaging trait, helpful in the low-light depths of the ocean.
Stiller and her team are already making a push for the ruby sea dragon to receive the same types of conservation protections afforded to the other sea dragon species to keep this brightly-colored sea creature safe.