Plectranthias takasei is the newest species of reef fish to be described and what a fantastic new fish it is. This attractive ‘Hinomaru Perchlet’ also has the honor of being described by some serious fish nerds, including the Ichthyologist formerly known as Lemon TYK.
Of all the ‘mysterious’ groups of aquarium suitable reef fish, the Plectranthias are definitely among our favorites. Ranging from the ubiquitous Plectranthias inermis, to the rare P. pelicieri, to the handful of species that are officially undescribed and poorly known.
Plectranthias takasei joins an illustrious group of fish, many of which are found in the Northwest Pacific Ocean and Japan, such as this one. Since it comes from Japan and has an obvious big red spot on its side, the common name of Plectranthias takasei is the Hinomaru Perchlet, with Hinomaru being Japanese for ‘circle of the sun’, and a common reference to the Japanese flag.
But Plectranthias takasei is not the only species with that distinctive red spot, sharing this feature, and its range with the larger Plectranthias yamakawai. And there’s another perchlet in this genus with a distinctive red spot on its side too, which has sometimes been confused with the Hinomaru Perchlet, which is tentatively undescribed.
The newly minted Plectranthias takasei was first collected in march 2008 at Izu Oceanic Park, in Sagami Bay, Honshu, Japan. Interestingly, this is also the home of the Sagami perchlet, Plectranthias sagamiensis but thankfully, this species was found at the modest depth of 55 meters, or about 180 feet deep.
Like Cichlasoma for new world cichlids and Pseudotropheus for African cichlids, the Plectranthias genus is starting to get bloated into a catch-all for all of the perchlets with this particular body shape. The taxon likely represents multiple groups of fish and a formal revision in the future will likely result into the Plectranthias species being divided into more cohesive genera.
The Hinomaru Perchlet, Plectranthias takasei is described by Gill, Tea & Senou in the latest edition of ZooTaxa.