Halichoeres hilomeni, Randall & Allen, 2010

Randall, John E. & Allen, Gerald R., 2010, Two New Labrid Fishes Of The Genus Halichoeres From The East Indies, Raffles Bulletin of Zoology 58 (2), pp. 281-289 : 286-288

Halichoeres hilomeni , new species

( Figs. 8–12 ; Table 2)

Halichoeres exornatus (non Richardson, 1846) Kuiter, 2002: 115, Figs. A, B. Philippines and Borneo, Malaysia.

Material examined. – Holotype – UPLB 498 , male, 95.6 mm, Philippines, Palawan Province, Dibuluan Island, Bacuit Bay , southern end of bay, 12.8 km south of town of El Nido, 11°04.320'N 119°22.301'E, reef, 1–3 m, spear, M. V. Erdmann, 12 Jun.2008.

Paratypes. – BPBM 41024 , 2 : 55.0– 91.5 mm ; UPLB 495 , 75.5 mm ; UPLB 500 , 45.6 mm ; USNM 398628 , 2 : 73.5–81.3 mm ; WAM P.33270.001, 2: 57.7–77.9 mm; ZRC 52402, 59.4 mm, all with same data as holotype .

Diagnosis. – Dorsal rays IX,12; anal rays III,12; pectoral rays 14; lateral-line scales 27; head naked; nape fully scaled; most scales of straight anterior part of lateral with a middle surface tubule forming three short branches ending in a pore, the middle branch usually longest; suborbital pores 10–13; gill rakers 18–20; body depth 3.15–3.6 in SL; head length 2.9–3.0 in SL; snout length 2.85–3.25 in head length; dorsal spines progressively longer posteriorly, the last three subequal, 2.85–3.4 in head length; caudal fin moderately rounded, 1.35–1.5 in head length; upper half of body dark brown, males with five narrow pale bars extending from base of dorsal fin; lower half of body pale brown, the centres of scales darker; a dark brown band from upper lip to lower half of orbit, extending posterior to eye, half as broad, to base of opercular flap; three narrow dark bars extending dorsally from postorbital band, the first black and vertical, just behind eye, the posterior two bands irregular; a boomerang-shaped dark brown band extending posteriorly from behind corner of mouth across cheek; fins translucent pale yellowish, the dorsal with a broad black band across middle of first two membranes; rest of fin with longitudinal rows of faint, darkedged, pale spots (three per membrane); anal fin with a row of faint, dark-edged, pale spots along base; caudal fin with faint transverse bands; paired fins pale, the pectorals with a triangular black spot dorsally on base, narrowing to a line across remainder of base; peritoneum dark brown. Largest specimen, 95.6 mm SL.

Description. – Dorsal rays IX,12; anal rays III,12 (one with 10, the fin deformed); all dorsal and anal rays branched, the last to base; pectoral rays 14, uppermost rudimentary, second unbranched; pelvic rays I,5; principal caudal rays 14, upper and lower unbranched; upper procurrent caudal rays 7; lower procurrent caudal rays 6; lateral-line scales 27, plus 1 pored scale on caudal-fin base; scales above first lateral-line scale to base of second dorsal spine 3.5; scales above lateral line to base of ninth dorsal spine 2.5; scales below lateral line to base of first anal spine 8.5; circumpeduncular scales 20; gill rakers 19 (18–20); branchiostegal rays 5; vertebrae 25.

Body depth 3.15 (3.15–3.6) in SL; body moderately compressed, width 2.3 (2.0–2.3) in body depth; head length 2.9 (2.9–3.0) in SL; snout length 3.05 (2.85–3.15) in head length; orbit diameter 5.4 (4.55–5.3) in head length; interorbital space convex, least width 5.4 (5.0–5.4) in head length; caudal-peduncle depth 2.0 (1.95–2.1) in head length; caudal-peduncle length 4.05 (3.5–4.05) in head length.

Mouth terminal and a little oblique, upper-jaw length 3.3 (3.25–3.65) in head length; 10 strong, close-set, conical teeth in outer row on side of upper jaw, and 12 in lower jaw, progressively longer and more jutting anteriorly, the anterior three slightly recurved; anteriormost tooth in jaws a canine about three-fourths pupil diameter in length; lower pair of canines fitting inside upper pair when mouth closed; canine tooth at posterior end of upper jaw, its length about two-thirds length of anterior canines; inner row of small nodular teeth in both jaws. Tip of tongue narrowly rounded, reaching only corner of jaws. Lips large, fleshy, and deeply furrowed medially; median dorsal length of upper lip equal to pupil diameter; curving labial flap on side of lower jaw about half pupil diameter at its greatest depth. Gill rakers short, the longest about one-third length of longest filaments on first gill arch (gill arch on left side of holotype badly deformed, perhaps from parasite damage, though none was found).

Anterior nostril a very small, tapering tubule a pupil diameter before anterior edge of orbit at level of middle of eye; posterior nostril a small ovate aperture, three-fifths pupil diameter dorsoposterior to anterior nostril. Suborbital pores 13 (10–13); pores of preopercular-mandibular series 13 (13–15).

Scales cycloid; lateral line continuous, deflected downward below last two dorsal soft rays to straight peduncular part; scales of straight portion of lateral line mostly with a middle surface tubule forming three short branches ending in a pore, the middle branch usually longest; peduncular part of lateral line with a straight surface tubule ending in a pore; nape fully scaled, with about nine oblique rows of scales, progressively smaller and more embedded anteriorly, reaching a vertical at posterior edge of eye; scales of prepelvic area progressively smaller anteriorly, just reaching gill opening, about 11 in midventral series; no scales on base of dorsal, anal, and paired fins, except for a triangular scale nearly a pupil diameter in length with a small basal scale at midbase of pelvic fins; basal third of caudal fin with four vertical rows of scales, progressively smaller posteriorly.

Origin of dorsal fin above second lateral-line scale, predorsal length 3.2 (2.95–3.2) in SL; dorsal spines progressively longer, last three subequal, first 5.55 (5.2–5.75) in head length, and ninth 3.2 (2.85–3.45) in head length; third to ninth dorsal soft rays longest and subequal, 2.5 (2.45–2.65) in head length; origin of anal fin below base of first dorsal soft ray, preanal length 1.8 in SL; first anal spine very slender and short, 8.4 (6.75–10.0) in head length; third anal spine 4.55 (3.85–4.55) in head length; second to tenth anal soft rays subequal, 2.75 (2.4–2.9) in head length; caudal fin moderately rounded, 1.44 (1.35–1.5) in head length; second or third pectoral rays longest,1.75 (1.55–1.7) in head length; origin of pelvic fins below lower edge of pectoral-fin base, prepelvic length 3.0 (3.0–3.1) in SL; pelvic fins reaching or extending slightly beyond origin of anal fin only in large males, fin length 1.45 (1.45–1.95) in head length.

Colour of holotype in alcohol: upper half of body dark brown, the pigment concentrated in a vertically elongate spot basally on each scale, with five narrow pale bars extending from base of dorsal fin; lower half of body pale brown, the centres of scales darker; a dark brown band from upper lip to lower half of orbit, extending posterior to eye, half as broad, to base of opercular flap; three narrow dark bands extending dorsally from postorbital band, the first black and vertical, just behind eye, the posterior two irregular; a boomerangshaped dark brown band extending posteriorly from behind corner of mouth across cheek; fins translucent pale yellowish, the dorsal with a broad black band across middle of first two membranes; rest of fin with three longitudinal rows of faintly dark-edged pale spots (three per membrane); anal fin with a row of similar spots along base, a vertically elongate, dark-edged pale spot on each membrane, and a submarginal dark-edged pale band; caudal fin with faint, irregular, cross bands; paired fins pale, the pectorals with a triangular black spot dorsally on base, narrowing to a line that nearly crosses remainder of fin base.

habitat of mixed coral, algae, sand and gravel. It was also observed and photographed at Coron Island in the Calamian Group north of Palawan, and in Borneo, based on an underwater photograph taken by the second author near Kota Kinabalu, Sabah, Malaysia ( Fig. 12).

The closest relative to Halichoeres hilomeni appears to be H. solorensis (Bleeker) , known from Indonesia and the Philippines. The two species share the same fin-ray, scale, and suborbital pore counts, and the gill-raker count is nearly the same, 17–19 for H. solorensis , compared to 18–20 for H. hilomeni . Both have a black spot covering most of the first two dorsal-fin membranes, the same black spot at the pectoral-fin base, and dark brown peritoneum, but there the similarity in colour ends. The body of H. solorensis varies from a somber dark greenish grey to yellowish green, the head yellow with pink bands, and there is an ocellated small black spot at the upper base of the caudal fin. Judging from the juvenile colour pattern of H. solorensis , the juveniles of H. hilomeni should also have an ocellated black spot in the soft portion of the dorsal fin.

Material of Halichoeres solorensis examined. – Indonesia: Flores, BPBM 32151, 48.5 mm; Komodo, BPBM 32392, 48 mm; Ambon, BPBM 18529, 90 mm. Philippines: Luzon, Maricaban Island, BPBM 22216, 8: 36–82 mm.

Colour in life shown in Figs. 9–12. Based on the relative size of eye to head length, Fig. 9 is a probable female about 55 mm SL; Fig. 10 about 57 mm SL (perhaps undergoing sex reversal); Fig. 11 a male about 75 mm SL, and Fig. 12 a male about 90 mm SL.

Etymology. – This species is named in honour of Dr. Vincent V. Hilomen of the University of the Philippines Los Baños in recognition of his efforts in obtaining collection and export permits and arranging the shipment of the type specimens to the authors.

Remarks. – The type specimens were all collected from Dibuluan, a small island at the northern end of Palawan, Philippines. The species was found in 1–3 m in a sheltered

Figures

Fig. 8. Holotype of Halichoeres hilomeni, male, UPLB 498, 95.6 mm, Dibuluan Island, Palawan Province, Philippines (H. A. Randall).

Fig. 10. Halichoeres hilomeni, Dibuluan Island, Palawan Province, Philippines (G. R. Allen).

Fig. 11. Halichoeres hilomeni, male, Dibuluan Island, Palawan Province, Philippines (G. R. Allen).