Plectranthias yamakawai Yoshino, 1972

Cabebe-Barnuevo, Roxanne A., Delloro Jr, Emmanuel S., Penuela, Dianne Frances A., Malay, Maria Celia D., Motomura, Hiroyuki & Babaran, Ricardo P., 2022, New record of anthiadine fish, Plectranthias yamakawai (Actinopterygii: Perciformes: Serranidae), from the Philippines, Acta Ichthyologica et Piscatoria 52 (4), pp. 299-307 : 299

Plectranthias yamakawai Yoshino, 1972

(Figs 1 and 3

Material examined.

UPVMI-01360, 168.86 mm SL, Zambales fish market, the Philippines, 1 March 2022, leg. R.P. Babaran.

Morphological diagnosis and description.

Single specimen of Plectranthias yamakawai had following combination of characters: dorsal-fin spines X, dorsal-fin soft rays 18, anal-fin spines III, anal-fin soft rays 7, pectoral-fin rays 13, lateral-line scales 31, scales above lateral line 5, scales below lateral line 17, and gill rakers 6 + 10. Body compressed, moderately deep, depth 2.18 in SL; head large (length 2.19 in SL, depth 3.86 in SL), slightly convex dorsally. Mouth large, terminal; maxilla large, expanded easily, exposed when mouth closed; lower jaw significantly extending beyond upper jaw; opercle consisting of three spines (middle spine strongest and longest); preopercle serrated with three antrorse spines on lower margin of left side and two spines on right side; subopercle and interopercle margins not serrated. Teeth on both jaws minute; two enlarged conical teeth on right side and three on left side positioned anterior of upper jaw; single, enlarged, conical tooth positioned in middle area on both sides of lower jaw. Both vomerine and palatine patches consisting of villiform teeth; vomerine tooth patch V-shaped while palatine tooth patches narrow band-shaped. Teeth on tongue absent; base of tongue broad becoming narrow at front end. Scales on body large, ctenoid in shape; head area covered with scales except for snout, lips, maxillary, and ventral area; operculum completely covered with large scales; nape area covered with smaller scales; dorsal-, anal-, and pectoral-fin bases with small scales. Dorsal-fin spines stiff and connected to dorsal-fin soft rays; 4th dorsal-fin spine longest (26.48 mm vs. 5th spine 25.08 mm and 3rd spine 23.68 mm). Anal-fin spines long and rigid; 2nd anal-fin spine as longest (28.98 mm vs. 1st spine 14.09 mm and 3rd spine 27.65 mm). Pectoral-fin rays long, longest fin ray reaching beyond posterior end of anal-fin base, 1st pectoral-fin ray unbranched; 2nd-13th pectoral-fin rays branched. Pelvic fin inserted anterior to pectoral-fin base; longest pelvic-fin ray not reaching anus. Caudal fin emarginate; 5th-7th upper lobe-fin rays filamentous.

Color in fresh sample.

Body reddish-yellow (dorsal side) and white (ventral area) (Fig. 1A ); yellow-fringed dark greenish blotches scattered on upper half of body and head; similar blotches present in entire caudal peduncle, dorsal- and caudal-fin bases; smaller blotches observed in pre-dorsal area; large red spot located just below lateral line and center of body; pectoral fin reddish; dorsal, anal, pelvic, and caudal fin reddish-yellow; posterior end of dorsal-fin soft rays and caudal-fin ray edges both black.

Color of preserved sample.

Body light brown (Fig. 1B ); dark green blotches still visible; red spot faded; fins colorless; posterior end of dorsal-fin soft rays and caudal-fin ray edges remain black.

Distribution.

Plectranthias yamakawai is commonly collected from various fishing grounds in Ryukyu Islands, Japan ( Yoshino 1972; Motomura and Harazaki 2017; Wada et al. 2020), and reports of it have also come from Taiwan ( Chen and Shao 2002), and Samoan Islands ( Wass 1984), as well as the western coast of Luzon Philippines (Fig. 2 ).

Previous Philippine records.

Three of the five species of Plectranthias previously documented in the Philippines have been described as new species based on the Philippine specimens, P. foresti , P. inermis , and P. knappi , while the other two are documented as new records ( P. japonicus and P. sagamiensis ). Plectranthias foresti was described based on four specimens trawled at depths of 183-185 m off southwestern Luzon ( Fourmanoir 1977; Randall 1980). Plectranthias knappi , was discovered in the Visayan Sea from a single specimen obtained at 90 m deep ( Randall 1996). Similarly, the holotype of P. inermis was collected from Batangas, Southern Luzon Region, Philippines at 30 m deep, with later reports of the species from Mauritius, Christmas Island, Fiji, and Papua New Guinea ( Randall 1980; Fricke et al. 2022). Plectranthias sagamiensis , originally described in Japan ( Katayama 1964) was later collected off southwest Luzon at depths of 82-86 m and served as the first report of the species in the Philippines ( Iwamoto and McCosker 2014). Plectranthias japonicus was originally described in Japan ( Steindachner and Döderlein 1883) and first reported by Randall (1980) taken from 185-200 m off Manila Bay, Philippines.

Figures

Figure 1. Images of fresh (A) and preserved (B) Plectranthias yamakawai, UPVMI- 01360, 168.86 mm SL collected off Zambales, Western coast of Luzon, the Philippines.

Figure 2. Distribution of Plectranthias yamakawai, based on published records and the presently reported study.

Figure 3. Antrorse spines observed on both sides of the Plectranthias yamakawai from the Philippines.