3 days ago
Five-armed creature — covered in ‘axes' — found off Taiwan. See the new species
In the rocky intertidal zones along the coast of Taiwan, a five-armed creature scuttles along the seafloor.
Its brown, green and black body blends in with the colorful rocks as it glides across the bottom.
The animal is a brittle star — and a new species.
Brittle stars, or ophiurida, may look like classic starfish, but their long and flexible arms set them apart from their more rigid cousins.
They can move quickly thanks to muscles that move a series of vertebrae-like structures linked together with ball-and-socket joints, according to the University of California at Berkeley.
The new brittle star was collected off the southern coast of Taiwan and around a few barrier islands, according to a study published June 6 in the peer-reviewed European Journal of Taxonomy.
The animal's central structure, or dorsal disc, is 'covered with fine granules,' according to the study, while the arms are covered in spines.
The long arms are made up of spiny plates that fit together like puzzle pieces, photos show.
The pattern on the arms also gives the new species its name, researchers said.
Breviturma securis, or the axe brittle star, derives its name from the Latin word 'securis' meaning axe, 'referencing the axe-shaped dark patterns on the dorsal arm plates,' according to the study.
The body as a whole is 'yellowish-gray to greenish-gray' with 'lighter and darker patches,' researchers said.
'These regions are adorned with discontinuous short dark lines that never form a reticular pattern,' according to the study. 'In juveniles, a dark 'star' may occasionally appear at the center of the disc but never connects to the arm base.'
The brittle stars live in the sandy material below rocks from intertidal zones to shallow waters around 25 feet deep, researchers said. They are also commonly found in the same areas as other related brittle star species.
Breviturma securis was previously misidentified as another species and appeared in a series of field guides and photographs under the wrong name, according to the study.
The new research, with DNA confirmation, will allow these resources to be updated, researchers said.
The holotype, or primary specimen used to describe the new species, was found in Taitung County on Taiwan's southeastern coast.
The research team includes Kai Chang and Hsi-Te Shih.
