Mysterious new species of seadragon discovered


Scientists have discovered a third species of seadragon from Western Australia - and it's bright red.

Researchers from Scripps Institution of Oceanography found evidence of the new seadragon while analysing tissue samples of the two known species, the Leafy and the Common seadragon, from the Western Australia Museum (WAM), using DNA and anatomical research tools.

They then requested the full specimen as well as photographs taken just after it was retrieved from the wild in 2007. They were further surprised by the appearance of the newly identified animal. The colour was a bright shade of red and vastly different from the orange tint in Leafy seadragon (Phycodurus eques) and the yellow and purple hues of Common seadragon (Phyllopteryx taeniolatus).

The scientists gave their new discovery the scientific name Phyllopteryx dewysea, also referred to as the Ruby seadragon.

"A CT (computer tomography) scan gave us 5,000 X-ray slices that we were able to assemble into a rotating 3-D model of the new seadragon," said Scripps graduate student Josefin Stiller . "We could then see several features of the skeleton that were distinct from the other two species, corroborating the genetic evidence."

The team believes the animal’s colouring suggests it inhabits deeper waters than the Leafy and Common Seadragons, as the red shading would be absorbed at depth and effectively serve as camouflage.

Following the initial finding, a trawl through the collection at Western Australia Museum yielded a second Ruby seadragon specimen that had washed up on a Perth beach nearly a hundred years ago, and Stiller tracked down two others archived in the Australian National Fish Collection.

"This new seadragon first entered the Western Australia Museum’s collection in 1919, and lay unidentified for almost a century," said marine biologist Nerida Wilson. "Recognising this new species demonstrates how museum collections underpin biodiversity discovery."

The authors now hope to put together a search expedition for Ruby seadragons and witness them alive in the wild.

"It has been 150 years since the last seadragon was described and all this time we thought that there were only two species," said Wilson. "Suddenly, there is a third species! If we can overlook such a charismatic new species for so long, we definitely have many more exciting discoveries awaiting us in the oceans."

For more information see the paper: A spectacular new species of seadragon (Syngnathidae) Josefin Stiller, Nerida G. Wilson, Greg W. Rouse. R. Soc. open sci.: 2015 2 140458; DOI: 10.1098/rsos.140458.

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