Near the central coast of Japan, a fishing vessel discovered a vibrant, red, bumpy sea creature on the ocean floor. Scientists have identified this remarkable find as a previously unknown species of starfish.
The identification of this new species resulted from the collaborative endeavors of researchers from the University of Tokyo, the Marine Science Museum, Enoshima Aquarium, Fukushima Prefecture, and the Yamaguchi Prefectural Fisheries Research Center in Japan.
The newly identified starfish, Paragonaster hoeimaruae, is a member of the Pseudarchasteridae family. This group of echinoderms inhabits shallow to medium-depth ocean environments. These starfish distinguish themselves with their flat bodies and the distinctive ‘block-like’ plates on their arms.
The newly discovered species closely resembles others in its appearance. It features five robust legs adorned with bumps, with some plates being oblong and others circular or rectangular. The sea star showcases a red exterior, contrasting with a beige underside. Suckered discs located on its body facilitate its movement across the ocean floor.
Scientists recognize approximately 2,000 species of starfish, and they have found 250 of these around Japan. To date, researchers have documented only four species of Pseudarchasteridae in Japanese waters, including a newly discovered species, all of which live at depths ranging from 500 to 1,100 feet.
“We identified a new starfish species, now known as Paragonaster hoeimaruae, near the Izu Peninsula in Sagami Bay, south of Tokyo. Additionally, we encountered another specimen in the Sea of Japan, to the northwest of Yamaguchi Prefecture in southwestern Japan,” stated Itaru Kobayashi, the lead researcher from the Misaki Marine Biological Station at the University of Tokyo.
From 2021 to 2023, our research team collected diverse species from various locations across Japan. These specimens were sourced by local fishermen in the Hokkaido and Shizuoka prefectures, situated in the northern and central regions of the country.
The fishermen utilized shrimp and crab traps, along with large nets, to capture marine life. They named the starfish after the vessel, the Hoei-maru, that retrieved it from the depths.
One remarkable species of starfish discovered by the researchers was Gephyreaster swifti, identified off the northern coast of Hokkaido. Prior to this finding, Gephyreaster swifti had only been recorded along the Pacific coast of the United States and Canada, extending to the northern islands of the Bering Sea.
According to the Pacific Beach Coalition, starfish aren’t true fish. Although their name suggests otherwise, they’re actually more closely related to sand dollars, spiky sea urchins, and soft sea cucumbers.
Although they may appear weak and vulnerable when stranded on a beach, these creatures are vital predators in their ecosystem. Lacking both a brain and blood, they rely on their small suction cups to capture their prey.
The identification of *Paragonaster hoeimaruae* highlights the crucial role of collaboration among researchers in advancing scientific knowledge. It also underscores the extensive exploration required to reveal the full range of marine biodiversity.
