Plectranthias raki (Teleostei, Serranidae), a new species of perchlet from mesophotic coral ecosystems of the Maldives

Herein, we describe a new species of <i>Plectranthias</i> perchlet found at depths of 100-125 meters in mesophotic coral ecosystems of the Maldives in the Indian Ocean. <i>Plectranthiasraki</i> <b>sp. nov.</b> is unique in both morphology and coloration. The following combination of characters distinguishes it from all known congeners: dorsal fin X, 15; anal-fin rays III, 7; pectoral-fin rays 13 | 13 (13 | 12), all unbranched; principal caudal-fin rays 9 + 8; lateral line complete with 30-32 tubed scales; gill rakers 5 + 12; circumpeduncular scales 11-12; and absence of antrorse or retrorse spines on ventral margin of preopercle. Coloration in life consists of a white to light pink body with two indistinct rows of irregularly shaped red-orange to yellow-orange patches along the dorsal two-thirds of the body, a golden-yellow opercle and maxilla, an indistinct yellow stripe on the dorsal fin, two yellow spots near the base of the anal fin, and two irregularly shaped yellow-orange spots located on either side of centermost caudal-fin rays. With this publication, the genus <i>Plectranthias</i> now comprises 67 valid species. This discovery adds to a strong body of research highlighting the novel biodiversity of mesophotic ecosystems, especially in locations like the Indian Ocean, where few prior ichthyological surveys have been conducted.