Nemipterus sugillatus, Russell, Barry C. & Ho, Hsuan-Ching, 2017

Russell, Barry C. & Ho, Hsuan-Ching, 2017, A new species of Nemipterus (Perciformes: Nemipteridae) and first record of N. nematophorus (Bleeker) from Taiwan, Zootaxa 4231 (2), pp. 281-288 : 282-286

Nemipterus sugillatus n. sp.

New English name: Bluecheek threadfin bream Figures 1 A–C, 2. Table 1

Nemipterus tambuloides (non Bleeker 1853): Gloerfelt-Tarp & Kailola 1984: 188 (figure) ( Indonesia). Nemipterus virgatus (non Houttuyn 1872): Gloerfelt-Tarp & Kailola 1984: 337 (voucher specimen) ( Indonesia). Nemipterus sp. 1: Russell 1990: 52 ( Indonesia).

Nemipterus sp. A: White et al. 2013: 226 ( Indonesia).

Holotype. ASIZ-P80855, 201.0 mm SL, purchased from Hengchun market, collected by hook and line at Kenting region, southern tip of Taiwan, ca. 100 m, 5 July 2016.

Paratypes. (17: 93.5–255.5 mm SL). BMNH ̇1984.8.20: 13, 255.5 mm SL, Indonesia, off Bali , PJPẆ569, bottom trawl, August 1980; BMNH ̇1984.8.20: 14, 178.8 mm SL, Indonesia, Bali (8° 26'S, 114° 29'E) , PJPẆ706, bottom trawl, 71–82 m, 21 August 1980; CSIRO H5974-23, 206.0 mm SL, Indonesia, Bali, Kedonganan fish market, 5 October 2002 ; CSIRO H7306-02, 146.9 mm SL, Indonesia, Java, Pelabuhan Ratu fish market, 28 Oct 2008 ( BOLD FOAM 423-10 ) ; CSIRO H8042-01, 177.4 mm SL, Indonesia, Java, Pelabuhan Ratu fish market, 15 Oct 2008 ( BOLD FOAH 784-08 ) ; CSIRO H8042-02, 157.7 mm SL, same data as CSIRO H8042-01 ( BOLD FOAH 785-08 ) ; CSIRO H8042-03, 201 mm SL, same data as CSIRO H8042-01 ( BOLD FOAH 786-08 ) ; CSIRO H8043-01, 93.5 mm SL, Indonesia, Java, Sadeng fish market, 4 July 2008 ; MZB 23209, 170.1 mm SL, same data as CSIRO H7306-02 ( BOLD FOAM 422-10 ); NMMB-P 23610, 193.2 mm SL, purchased from Hengchun market, Pingtung, Taiwan, ca. 100 m, 4 July 2016 ; NTM ̇S.11004-001, 231.0 mm SL, male, Indonesia, south coast of Java, TGṪ2573, bottom trawl, 65 m, 16 May 1983 ; NTM ̇S.11022-001, 2: 121.8–167.0 mm SL, Indonesia, Bali Strait, TGṪ697, bottom trawl, 71–82 m, 21 August 1980 ; NTM S.11348-006, 105.3 mm SL, Indonesia, Lombok, off Tanjung Sangoela (8°59'S, 116°26'E), FRV " Bawal Putih II ", BCR 84-38, Engel trawl, 120–125 m, 21 August 1984 ; NTM S.12693-003, 199.0 mm SL, Indonesia, Bali ; PPO NCIP 4012, 172.4 mm SL, male, same data as NTM S.11348-006 ; PPO NCIP 4013, 102.6 mm SL, immature female, same data as NTM S.11348-006.

Diagnosis. Pectoral-fin rays ii, 14–15; gill rakers 10–12; body moderately elongate, depth 3.2–3.6 in SL; head length equal to or a little more than body depth; diameter of eye about equal to or a little less than snout length, 0.9– 1.4 in snout; lower margin of eye just above a line from tip of snout to upper pectoral-fin base; suborbital moderately deep, its lower edge slightly emarginate, least depth 1.2–1.7 in eye diameter; imaginary line extended upward from posterior edge of suborbital reaching dorsal profile somewhere between 3–7 scale rows before origin of dorsal fin; pectoral fins moderately long, reaching to or just beyond level of vent; pelvic fins very long, reaching to or just beyond origin of anal fin; caudal fin with upper rays pointed or produced to form short filament.

Description. Counts and proportional measurements are provided in Table 1 . Dorsal-fin rays X,9; anal-fin rays III,7; pectoral-fin rays ii,15 (ii, 14–15); lateral-line scales 47 (46–47); transverse scale rows 3.5/9.5 (3–4/9–10), gill rakers 12 (10–12).

Body depth 3.6 (3.2–3.5) in SL; head length 3.4 (3.0–3.4) in SL; head length equal to or a little more than body depth, depth 1.0 (1.0–1.2) in head; snout short, straight to slightly rounded in profile, 3.0 (2.9–3.5) in head; eye 3.6 (2.9–4.1) in head; diameter of eye about equal to or less than snout, 1.2 (0.9–1.4) in snout; lower margin of eye just above a line from tip of snout to upper pectoral-fin base; interorbital width 1.3 (1.2–1.9) in eye; least depth of suborbital 1.4 (1.2–1.7) in eye; ventral margin of suborbital slightly emarginate, its posterior edge more or less straight; an imaginary line extended upward from posterior edge reaching dorsal profile about 3–7 scale rows before origin of dorsal fin; margin of preopercle weakly denticulate; caudal peduncle depth 1.4 (1.2–1.5) in peduncle length; dorsal-fin length 1.9 (1.8–2.0) in SL; fourth through tenth dorsal spines longest, 1.2 (1.1–1.5) times length of first dorsal spine; fifth through seventh dorsal rays longest, 1.4 (1.1–1.5) times length of longest dorsal spine; anal-fin length 4.9 (4.5–5.5) in SL; third anal-fin spine longest; first anal spine (1.6–2.4) in second; second anal spine (1.0–1.2) in third; pectoral fins moderately long, reaching to or just beyond level of vent, 1.1 (1.1–1.3) in head; pelvic fins very long, reaching to or just beyond origin of anal fin, 1.2 (0.9–1.4) in head; pectoral fins 1.2 (0.9–1.4) in pelvic fins; caudal fin forked, upper rays pointed or produced to form short filament.

Maxillary reaching to below anterior margin of eye; jaw teeth small, pointed, in narrow tapering bands in both jaws; upper jaw with outer row of 3–4 pair of small, recurved canines anteriorly; lower jaw with outer row of 4 pair of slightly enlarged canines anteriorly; 4–5 small canines laterally on either side of lower jaw.

Colour in life ( Fig. 1 A, C): body silvery pink with bluish iridescent tinges, darker above; 5 pale golden yellow stripes on sides beneath lateral-line; ventral surface silvery white with broad lemon-yellow stripe on either side of ventral midline; head with golden or silvery iridescent reflections; ovoid-shaped, pinkish mauve or bluish blotch extending from beneath eye to upper part of opercle; eye pinkish silver; upper lip yellow anteriorly; dorsal fin pale pink, with broad yellow margin edged below by red; greyish mauve submarginal stripe on posterior half of fin; anal fin translucent pinkish with reddish margin and narrow dark yellow submarginal stripe, another narrow yellow stripe a short distance from the base of fin, extending to tip of last anal fin ray; caudal fin pink, upper tip yellow; pelvic fins pinkish, with bright yellow stripe along second ray from base to tip of fin; pectoral fins pinkish; peritoneum silvery white.

Colour in alcohol ( Fig. 1 B): Body uniformly pale brown; narrow, dusky submarginal stripe along dorsal fin.

Etymology. Named sugillatus from the Latin for bruise, in reference to the pinkish mauve or bluish bruise-like blotch on the upper part of the opercule. The common name Bluecheek threadfin bream is proposed for this species.

Comparisons. Nemipterus sugillatus n. sp. ( Fig 1 A, C) superficially resembles N. virgatus (Houttuyn) in colour pattern ( Fig. 1 D) but differs from the latter, notably in lacking a second yellow stripe along the base of the dorsal fin, and by the absence of a red spot at the origin of the lateral-line. Nemipterus virgatus also is unique amongst Nemipterus in having 8 anal-fin soft rays (versus 7 in N. sugillatus n. sp. and all other species), and has a long trailing caudal filament (filament short or lacking in N. sugillatus n. sp.). It is distinguished from other species of Nemipterus known from Taiwan in the key provided below.

Remarks. A photograph of this species, first collected during the JETINDOFISH survey of Indonesian waters, was mistakenly figured as Nemipterus tambuloides by Gloerfelt-Tarp & Kailola (1984: 188) and the voucher specimen (TGT 2573, NTM S.11004-001) incorrectly identified as N. virgatus ( Gloerfelt-Tarp & Kailola 1984: 337) [the correct figure of N. tambuloides was mislabelled N. virgatus by Gloerfelt-Tarp & Kailola (1984: 188)].

Russell (1990) recognised the species as distinct and included it as Nemipterus sp. 1 in his FAO species catalogue of nemipterids of the world. Subsequently, specimens were collected during an Indonesian - German Technical Cooperation Agency (GTZ) trawl survey around the island of Lombok ( Wörner 1984), as well as from fish market surveys on the south coast of Java and Bali as part of a collaborative project between Australia and Indonesia ( White et al. 2013); and most recently from a market in Hengchun, southern Taiwan. According to the fish seller, Hengchun specimens were locally caught by hook and line fishing off the southern tip of Taiwan at a depth around 100 m.

Distribution. Nemipterus sugillatus n. sp. is thus far known only from specimens collected in Indonesia (south coast of Java, Bali and Lombok) and southern Taiwan ( Fig. 2 ). Indonesian specimens were trawled in depths between 65–125 m and Taiwan specimens were taken by hook and line in about 100 m.

Figures

FIGURE 1. Nemipterus sugillatus n. sp. A. holotype, ASIZP-P 80855, fresh coloration. B. Preserved holotype. C. Paratype, NMMB-P 23610, fresh. D. Nemipterus virgatus, CSIRO H 7071 - 01, 173 mm SL, Hong Kong.

FIGURE 2. Distribution map of Nemipterus sugillatus n. sp. Star indicates the holotype collection locality; red dots represent Indonesian collection localities.

Tables

TABLE 1. Counts and proportional measurements (given as ratio) of the type series of Nemipterus sugillatus n. sp.

Specimens	Holotype ASIZ-P80855 201.0 mm SL	Paratypes (17) 93.5–255.5 mm SL
Counts Dorsal-fin spines Dorsal-fin rays	10 9	10 9
Anal-fin spines Anal-fin rays Pectoral-fin branched rays	3 7 15	3 7 14–15
Lateral-line scales Transverse scale rows above lateral-line Transverse scale rows below lateral-line	47 3.5 9.5	46–47 3–4 9–10
Gill rakers (upper limb) Gill rakers (lower limb) Gill rakers (total)	6 6 12	4–7 6–8 10–12
Proportional measurements Depth in SL Head in SL	3.6 3.4	3.2–3.5 3.0–3.4
Depth in head length Snout length in head Eye diameter in head	1.0 3.0 3.6	1.0–1.2 2.9–3.5 2.9–4.1
Eye diameter in snout Interorbital width in eye Suborbital depth in eye	1.2 1.3 1.4	0.9–1.4 1.2–1.9 1.2–1.7
Peduncle depth in peduncle length Dorsal-fin length in SL Anal-fin length in SL	1.4 1.9 4.9	1.2–1.5 1.8–2.0 4.5–5.5
Pectoral-fin length in head Pelvic-fin length in head Pectoral-fin length in pelvic fin 1st dorsal spine in longest dorsal spine	1.1 0.9 1.2 1.2	1.1–1.3 0.8–1.3 0.9–1.4 1.1–1.5
Longest dorsal spine in longest dorsal ray 1st anal spine in second	1.4 –	1.1–1.5 1.6–2.4
Second anal spine in third	–	1.0–1.2