Plectranthias raki: A new species of Perchlet from the Maldives.

The term 'Perchlet' applies to a wide variety of small Perciform Fish. The genus Plectranthias is a member of the Serranidae, the family which also includes Sea Bass and Groupers, amongst other groups. It currently contains 66 described species from mesophotic reef environments in the Atlantic, Pacific, and Indian Oceans. Plectranthias are small Fish, typically 5-10 cm long with the largest species reaching about 20 cm, which live in holes or crevices, from where they ambush small, mobile invertebrates. The small size and cryptic nature of Plectranthias means that they are not well studied, with most species described from a very small number of specimens.

In a paper published in the journal ZooKeys on 16 January 2024, Bart Shepherd of the Steinhart Aquarium at the California Academy of Sciences, Hudson Pinheiro of the Department of Ichthyology at the California Academy of Sciences, and the Center for Marine Biology at the University of São Paulo, Ahmed Najeeb, also of the Department of Ichthyology at the California Academy of Sciences, and of the Maldives Marine Research Institute, Claudia Rocha, again of the Department of Ichthyology and of the Department of Microbiology at the California Academy of Sciences, and Luiz Rocha, once again of the Department of Ichthyology at the California Academy of Sciences, describe a new species of Plectranthias from the Kuramathi Outer Reef on Rasdhoo Atoll in the Maldives.

The new species is described from two specimens collected by hand-netting at a depth of 118 m, in December 2022, and confirmed as a new species by gene-sequencing. It is named Plectranthias raki, where 'raki' means 'feeling shy to confront people' in the Dhivehi language which is spoken in the Maldives.

Living specimen (not retained) of Plectranthias raki photographed at 110 m depth at Dhaalu Atoll, Maldives. Luiz Rocha in Shepherd et al.  (2025).

The two specimens of Plectranthias raki are 66.15 and 70.41 mm long, and pinkish white in colour with a series of irregular orange-red patches, these being more red towards the tail and more yellow towards the head. Both have dorsal fins with fifteen rays, anal fins with seven rays, pectoral fins with thirteen rays, and tail fins with nine upper rays and eight lower rays.

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A new species of Serranine Perchlet from the Philippines.

The Philippines form a major component of the Indo-Malay-Philippine Archipelago, which is considered to be a major biodiversity hotspot, with the highest diversity among coastal marine Fishes seen anywhere in the world, and many new species described every year. As such the country regularly visited by scientific vessels from major research organisations, looking for new fish species in the waters around its many islands, atolls and reefs. However other scientists have taken to searching the numerous Philippine Fish markets, looking for undescribed species caught by local fishermen.

In a paper published in the journal Zootaxa on 19 January 2015, Jeffrey Williams of the Division of Fishes at the Department of Vertebrate Zoology at the National Museum of Natural History of the Smithsonian Institution and Kent Carpenter of the Department of Biological Sciences at Old DominionUniversity, describe a new species of Serranine Perchlet from a specimen obtained from the Public Fish Market in Iloilo City.

The new species is placed in the genus Chelidoperca, and given the specific name santosi, in honour of the Philippine researcher Mudjekeewis Santos of the Department of Agriculture, Bureau of Fisheries and Aquatic Resources and National Fisheries Research and Development Institute in Manila, for his contributions to the advancement of science in the Philippines and help with the project which discovered the new species.

The specimen was found in the mouth of a large Grouper, which the vendor reported had been imported in a consignment of Fish from Palawan. A subsequent search of specimens in the collections of major museums, universities and other research institutes found two further specimens in the collection of Museum Victoria and the National Museum of Natural History of the Smithsonian Institution.

The new species is a small Perchlet, 69-84 mm in length. It is white on its underside, with pinkish markings towards the underside. The upper side is mottled pinkish and yellowish orange, with four dark spots between the eyes and two on the lower lip. Its fins are white, with yellow markings.

Specimen of Chelidoperca santosi from the Public Fish Market in Iloilo City, shortly after being discovered. Jeffrey Williams in Williams & Carpenter (2015).

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