Terelabrus zonalis, Fukui, 2018

Fukui, Yoshino, 2018, A new species of Terelabrus (Perciformes: Labridae) from the Philippines with a key to species of Terelabrus and new record of Terelabrus dewapyle, Zootaxa 4526 (1) : -

Terelabrus zonalis sp. nov.

New English name: Striped Hogfish

( Figs. 1–4 ; Table 1)

Holotype. MNHN 2005-0513 , 61.3 mm SL, off south coast of Mindoro island , the Philippines, 12°7ʹ 58.8ʺN, 121°16ʹ 58.8ʺE, 73–84 m, trawl, RV Coriolis, 3 June 1985.

Paratype. KAUM–I. 115925, 63.6 mm SL, same locality as holotype .

Diagnosis. A species of Terelabrus with the following combination of characters: 44 scale rows in longitudinal series; 42 pored lateral-line scales; 11–12 gill rakers, including rudiments; main supratemporal sensory canal with 8 branches; areas bounded by main supratemporal and postotic sensory canals (dorsal view) with 3 scale rows; least distance between anteroventral margin of orbit and maxilla 1.5–1.8 % of SL; least distance between anteroventral margin of orbit and ventral margin of interopercle 7.0 % of SL; caudal-procurrent rays in 9 dorsal and 9 ventral series; black blotch on opercle; and 18 faint silver vertical bands on body in preserved specimens.

Description. Data and description of holotype presented first, followed by that for paratype in parentheses when different.

Dorsal fin with 10 spines, 11 branched soft rays; anal fin with 3 spines, 12 branched soft rays; pectoral fin with 15 soft rays, all branched, except first and second; pelvic fin with 1 spine and 5 soft rays, third soft ray longest; principal caudal rays 14; branched caudal rays 12; scales rows in longitudinal series 44; pored lateral-line scales 42; scale rows above lateral line to origin of dorsal fin 3; scale rows below lateral line to origin of anal fin 10; gill rakers 12 (11); dorsal and ventral series of procurrent caudal-fin rays both 9; dorsal and ventral series of segmented unbranched caudal-fin rays both 2; dorsal and ventral series of branched caudal-fin rays both 6; formula for configuration of supraneural bones, anterior neural spines and anterior dorsal pterygiophores //0/1 + 1/1/1/1/1/1/1/ 1/1; vertebrae 11 + 17. All bi-lateral meristics same on both sides of body.

Body proportions (expressed as percentage of SL): body depth 16.4 (14.7); body width 12.8 (11.4); head length 31.9 (30.4); snout length 6.4 (6.8); orbit diameter 8.6 (8.8); interorbital width 4.2 (3.7); upper-jaw length 8.6 (8.8); postorbital length 14.3 (13.8); caudal-peduncle length 12.2 (12.6); caudal-peduncle depth 10.0 (9.0); pre-dorsal-fin length 32.4 (30.9); pre-anal-fin length 56.3 (56.4); pre-pelvic-fin length 32.2 (30.0); dorsal-fin base length 53.3 (49.1); first dorsal-fin spine length 5.1 (5.0); second dorsal-fin spine length 7.8 (7.5); third dorsal-fin spine length 8.6 (8.4); tenth dorsal-fin spine length 11.0 (10.8); longest dorsal-fin soft ray length 11.0 (10.8); anal-fin base length 30.7 (31.1); first anal-fin spine length 2.6; second anal-fin spine length 8.5 (8.3); third anal-fin spine length 10.3 (9.9); pectoral-fin length 14.3 (13.0); pelvic-fin length 14.3 (13.3); least distance between anteroventral margin of orbit and maxilla 1.5 (1.8).

Body elongate, cylindrical, slightly compressed anteriorly, becoming more compressed posteriorly. Snout moderately short, pointed. Eye extremely large. Interorbital space slightly convex. Mouth terminal, gape oblique; posterior margin of maxilla not extending to vertical through anterior margin of orbit; inner surface of upper lip with 5 oblique fleshy ridges with small dense papillae; inner surface of lower lip with 2 fleshy ridges; lower lip with thin flap extending ventrally on side of jaw. Teeth in jaws affixed to outer edge of bony ridge; 3 (4) large, slender, strongly curved canine teeth anteriorly in each jaw; 10 microscopic teeth posteriorly on bony plate behind upper-jaw canine teeth; 7 conical teeth along each side of upper jaw, followed posteriorly by 2 large curved canine teeth at end of upper jaw; row of 8 conical teeth along each side of lower jaw, followed by row of 7 (8) small teeth. Tongue slender, its upper surface covered with small papillae. Gill rakers short, compressed; rakers on upper limb shorter than those on lower limb; longest raker on first gill arch about half length of longest gill filament; gill membranes free from isthmus.

Nasal organ in oval chamber with convex cutaneous roof; anterior nostril small with short membranous tube. Supratemporal canal branched ( Fig. 2 ). Scales thin, cycloid; lateral-line scales continuous, following dorsal contour of body, posterior scales descending toward lateral mid-line; last 2 pored scales on base of caudal fin larger than anterior pored scales; each pored scale anteriorly on lateral line with upwardly angled tubule with a single terminal pore, each pored scale on lateral line near caudal fin base with single horizontal tubule. Scales on side of thorax becoming smaller anteriorly on isthmus. Scales in front of dorsal fin extending forward to vertical through preopercular margin, predorsal scales variable in size. Scales covering opercle, except for membrane. Size of largest scale behind orbit about one-third of those on opercle; scales behind orbit extending forward to anterior margin of orbit. No scales on fins, except base of caudal fin.

Preopercular margin smooth. Opercular membrane extending above upper base of pectoral fin. All dorsal-, anal-, and pelvic-fin soft rays branched; all pectoral-fin rays, except upper two, branched. Dorsal- and anal-fin spines slender. Pectoral fins weakly rounded, eighth ray longest; pelvic fins short, third soft ray longest; caudal fin rounded. Origin of dorsal fin posterior to vertical through origin of pectoral fin; posterior tip of pectoral fin posterior to vertical through base of sixth dorsal-fin spine; origin of pelvic fin slightly posterior to vertical through origin of pectoral fin; anus posterior to level of ninth dorsal-fin spine base; origin of anal fin below base of first dorsal-fin soft ray.

Color of preserved holotype and paratype ( Fig. 1 ). Body pale yellow; a poorly defined brown oval blotch on opercle, its maximum diameter subequal to orbit diameter; ca. 18 faint silver vertical bands on body; posterior edge of preopercle to base of pectoral fin whitish; fins translucent, except for brownish mid region of caudal fin.

Distribution. Currently known only from the Philippines ( Fig. 3 ).

Etymology. The new species is named zonalis (from Latin zona, meaning stripes), in reference to the vertical stripes on the body. Remarks. Terelabrus zonalis sp. nov. is uniquely characterized by higher counts of scale rows in longitudinal

series 44 (vs. 41 or 42 in T. dewapyle ) and pored lateral-line scales 42 (vs. 39 or 40 in T. dewapyle ); lower counts of gill rakers 11–12 (vs. 14 or 15 in T. rubrovittatus ) ( Table. 1); 8 posterior branches off the main supratemporal sensory canal (vs. 4–6 in T. dewapyle , 4–5 in T. rubrovittatus ); 3 scale rows in the area bounded by the main supratemporal and postotic sensory canals (dorsal view) (vs. embedded in T. flavocephalus ); shorter least distance between the orbit anteroventral margin and maxilla [1.5–1.8% (mean 1.7%) of SL vs. 1.2–3.7% (mean 2.5%) in T. dewapyle ]; greater least distance between the ventral margins of the orbit and interopercle [7.0 % of SL vs. 2.6– 5.5% (mean 3.5%) in T. dewapyle , 4.5% in T. flavocephalus , 3.4–4.4% (mean 3.7%) in T. rubrovittatus ]; 9 procurrent rays in both dorsal and ventral series in caudal fin (vs. 7–8 in T. dewapyle , 7 in T. flavocephalus , 8 in T. rubrovittatus ); larger predorsal bone, its width ca. five times that of other species of Terelabrus .

The preserved coloration of T. zonalis also differs from that of T. dewapyle , T. flavocephalus and T. rubrovittatus , in that it is the first record of silver vertical bands (18 faint) on the body in any of the recognized species.

New record of Terelabrus dewapyle . An individual Terelabrus specimen, photographed at 75 m depth off Nalusuan Island, the Philippines, was identified as T. dewapyle in having a yellow stripe between the upper and midlateral red body stripes, no red blotches superimposed on the midlateral red stripe, no yellow band on the dorsal fin and no vivid yellow stripes on the cheek. Terelabrus dewapyle has been previously recorded only from Japan, Papua New Guinea and Fiji on the basis of voucher specimens ( Randall & Fourmanoir 1998; Fukui & Motomura 2015), and from Indonesia and Japan from underwater photographs ( Kuiter & Debelius 2006; Motomura et al. 2010; Kuiter 2012; Allen & Erdmann 2012; Nishiyama & Motomura 2012). Therefore, the specimen photographed at Nalusuan Island represents the first evidence of T. dewapyle from the Philippines.

H indicates holotype.

* Scale counts could not be made on one T. dewapyle specimen due to body damage.

Figures

FIGURE 1. Terelabrus zonalis sp. nov., preserved. A, MNHN 2005-0513, holotype, 61.3 mm SL; B, KAUM–I. 115925, paratype, 63.6 mm SL.

FIGURE 2. Semi-diagrammatic illustration of head of holotype of Terelabrus zonalis sp. nov.. A, Lateral view; B, ventral view; C, dorsal view. STC, supratemporal sensory canal; POC, postotic sensory canal. Arrows point to STC branches. Scale 5 mm.

FIGURE 3. Distributional records of Terelabrus zonalis sp. nov. (stars), T. dewapyle (triangles), T. flavocephalus (square) and T. rubrovittatus (circles), based on specimens examined. Symbols with white centers refer to photographic records.

FIGURE 4. Relationships of least distance between anteroventral margin of orbit and interopercle with standard length in Terelabrus zonalis sp. nov. (stars), T. dewapyle (triangles), T. flavocephalus (square) and T. rubrovittatus (circles).