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A research group succeeded in discovering a previously unknown deep-water anthiasin in mesophotic reefs between the atolls Rasdhoo and Dhaalu, Maldives in the Indian Ocean.
So far, Plectranthias raki is only known from the Maldives, where this species is probably widespread.
The perches were observed in small holes in reef walls at several locations between the atolls of Rasdhoo and Dhaalu at a depth of about 100 to 125 meters.
The body of Plectranthias raki is pinkish-white with a series of irregularly shaped red-orange spots along the dorsal two-thirds of the body, the spots being red-orange dorsally and posteriorly, yellow-orange anteriorly and ventrally, the spots on the operculum bright golden yellow, especially on the maxilla.
A faint yellow stripe runs diagonally through the operculum from the lower eye margin, and a faint red stripe extends from the front eye margin to the upper lip.
The eye socket is white with a faint yellow stripe through the pupil.
The red-orange stripe that begins at the tip of the snout is sharply interrupted by the orange body spots along the lateral line, creating two distinct rows, which is particularly pronounced in live specimens;
The spots above the lateral line are smaller and connected to pairs or groups of three dorsal fin spines and rays, creating an alternating pattern of five orange spots interspersed with white areas along the base of the dorsal fin.
The spots below the lateral line are larger and more irregular in shape and distribution at the front, more rectangular and even on the rear half of the body.
The throat and belly are white, as is the dorsal fin at the base, while the interspinous membranes of the dorsal fin are usually yellow, white proximally, and hyaline distally.
The membranes of the soft dorsal fin are usually white with a yellow stripe approximately in the middle of the body and along the body contour, the dorsal fin spines are yellow, rays with yellow tips.
The anal fin is proximal mostly white, distal yellow, with two yellow spots, which are about one-third the diameter of the eye socket away from the base of the third spine and the fifth and sixth soft rays.
The anal fin spines are white, the pelvic fins proximal white, distal hyaline, with a yellow-orange spot at the base of the spine.
The pectoral fins are white to hyaline, with an orange spot measuring about half the diameter of the eye socket.
The caudal fin is white at the base, pale yellow distally, with two irregularly shaped yellow-orange spots measuring about one-third the diameter of the eye socket, located on either side of the central fin rays. Additional smaller spots of similar coloration are located distally the tips of the caudal fin rays are yellow, the proximal half of the dorsal and ventral caudal fin rays are yellow-orange.
Etymology:
The species name “raki” means “shy of encountering humans” in the Dhivehi language (also called Maldivian).
This name was chosen because Plectranthias are shy by nature and usually hide from us when we conduct research.
Literature reference.
Shepherd B, Pinheiro HT, Najeeb A, Rocha CR, Rocha LA (2025)
Plectranthias raki (Teleostei, Serranidae), a new species of perchlet from mesophotic coral ecosystems of the Maldives.
ZooKeys 1223: 333-344. https://doi.org/10.3897/zookeys.1223.135292
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
So far, Plectranthias raki is only known from the Maldives, where this species is probably widespread.
The perches were observed in small holes in reef walls at several locations between the atolls of Rasdhoo and Dhaalu at a depth of about 100 to 125 meters.
The body of Plectranthias raki is pinkish-white with a series of irregularly shaped red-orange spots along the dorsal two-thirds of the body, the spots being red-orange dorsally and posteriorly, yellow-orange anteriorly and ventrally, the spots on the operculum bright golden yellow, especially on the maxilla.
A faint yellow stripe runs diagonally through the operculum from the lower eye margin, and a faint red stripe extends from the front eye margin to the upper lip.
The eye socket is white with a faint yellow stripe through the pupil.
The red-orange stripe that begins at the tip of the snout is sharply interrupted by the orange body spots along the lateral line, creating two distinct rows, which is particularly pronounced in live specimens;
The spots above the lateral line are smaller and connected to pairs or groups of three dorsal fin spines and rays, creating an alternating pattern of five orange spots interspersed with white areas along the base of the dorsal fin.
The spots below the lateral line are larger and more irregular in shape and distribution at the front, more rectangular and even on the rear half of the body.
The throat and belly are white, as is the dorsal fin at the base, while the interspinous membranes of the dorsal fin are usually yellow, white proximally, and hyaline distally.
The membranes of the soft dorsal fin are usually white with a yellow stripe approximately in the middle of the body and along the body contour, the dorsal fin spines are yellow, rays with yellow tips.
The anal fin is proximal mostly white, distal yellow, with two yellow spots, which are about one-third the diameter of the eye socket away from the base of the third spine and the fifth and sixth soft rays.
The anal fin spines are white, the pelvic fins proximal white, distal hyaline, with a yellow-orange spot at the base of the spine.
The pectoral fins are white to hyaline, with an orange spot measuring about half the diameter of the eye socket.
The caudal fin is white at the base, pale yellow distally, with two irregularly shaped yellow-orange spots measuring about one-third the diameter of the eye socket, located on either side of the central fin rays. Additional smaller spots of similar coloration are located distally the tips of the caudal fin rays are yellow, the proximal half of the dorsal and ventral caudal fin rays are yellow-orange.
Etymology:
The species name “raki” means “shy of encountering humans” in the Dhivehi language (also called Maldivian).
This name was chosen because Plectranthias are shy by nature and usually hide from us when we conduct research.
Literature reference.
Shepherd B, Pinheiro HT, Najeeb A, Rocha CR, Rocha LA (2025)
Plectranthias raki (Teleostei, Serranidae), a new species of perchlet from mesophotic coral ecosystems of the Maldives.
ZooKeys 1223: 333-344. https://doi.org/10.3897/zookeys.1223.135292
This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
