Upeneus nigromarginatus, Bos, 2014

Bos, Arthur R., 2014, Upeneus nigromarginatus, a new species of goatfish (Perciformes: Mullidae) from the Philippines, Raffles Bulletin of Zoology 62, pp. 750-758 : 753-755

Upeneus nigromarginatus , new species

Black-margined goatfish ( Figs. 3–5 ; Tables 1, 2)

Material examined. Holotype ( Fig. 3 ): RMNH. PISC.37991, 1 ex., 196 mm SL; The Philippines, Panabo City, fish market, 7°18ʹ23ʺN, 125°41ʹ1ʺE, coll. A. R. Bos, 26 June 2012 . Paratypes: RMNH. PISC.36422, 1 ex., 151 mm SL ; RMNH. PISC.36423, 1 ex., 155 mm

SL; RMNH. PISC.36424, 1 ex., 156 mm SL ; RMNH. PISC.37992, 1 ex., 155 mm SL, same collection information as holotype .

Diagnosis. Meristic data of the holotype and the range and/or median of all type specimens are provided in Table 1. Data in parentheses refer to the paratypes when different from the holotype. Dorsal fin VIII + 9, first dorsal spine small, second dorsal spine longest, last dorsal soft ray branched to base. Anal fin I, 6, three paratypes with unusual two spines instead of one, with first spine short and thin ( Fig. 4 ), second spine up to two-third of first soft ray, first anal soft ray segmented and unbranched, last ray branched to base. Pectoral fin rays 16, upper 2 rays unbranched. Pelvic fin rays I, 5. Principal caudal fin rays 15 (15–16), uppermost and lowermost rays unbranched. Lateral line scales 36 (36–37), five scale rows between dorsal fins. Total gill rakers on first gill arch 25 (25–26). Gill rakers on upper and lower limb of first arch 8 + 17 (7–9 + 17–18), several anterior rakers undeveloped but visible on both limbs.

Proportional measurements of the holotype, paratypes, and the mean value of all specimens are presented in Table 2. Body relatively deep, its depth at first dorsal fin origin 2.9 (2.9–3.2) in SL. Body width 2.1 (1.8–2.2) in body depth. Anterior dorsal fin height 4.1 (4.0–4.1) in SL. Head length (HL) 3.4 (3.3–3.4) in SL. Snout relatively short, its length 3.4 (3.4–4.3) in HL. Orbit diameter 4.1 (3.6–3.9) in HL. Nostrils at horizontal axis of ventral edge of orbit. Mouth terminal and slightly oblique, the cleft forming an angle of about 10° to the horizontal axis of body. Both jaws with several rows of unevenly placed villiform teeth. Palatine and vomer with villiform teeth. Vomer with smaller teeth than those on palatine, forming rough surface covered by membrane tissue. Maxilla reaching vertical through anterior half of pupil, upper jaw length 2.3 (2.4–2.5) in HL. Barbels reaching vertical at two third of distance between orbit and posterior margin of pre-operculum, their length 1.5 (1.4–1.5) in HL.

Origin of dorsal fin over fifth lateral-line scale, pre-dorsal length 2.8 (2.7–2.8) in SL. Longest dorsal spine 1.2 in HL. First dorsal spine very short; pectoral fin relatively long, its length 1.0 (1.0–1.1) in HL. Pelvic fin length 1.5 (1.4–1.5) in HL. Caudal fin length relatively short, its length 1.0 (1.0–1.1) in HL. Caudal fin moderately forked, caudal concavity 1.9 (1.9–2.4) in HL. Caudal peduncle depth 2.3 (2.3–2.4) in HL. Caudal peduncle length 1.6 (1.4–1.7) in HL. Pre-anal length 1.4 (1.4–1.5) in SL. Anal fin height 1.8 (1.8–1.9) in HL.

Scales finely ctenoid. Sensory canals on lateral-line scales with four to six branches. A row of about 17 sensory canals on posterior edge of pre-operculum. Opercular membrane forms pointed lobe at horizontal axis of mid-eye position, but lacks a spine. Cheek and pre-operculum covered with scales. Small scales present basally on posterior dorsal and anal fin. Slender pelvic axillary scale about half the length of the pelvic fin.

Coloration in life. Coloration based on the freshly dead specimen of the holotype ( Fig. 3A ). Body and abdomen pearly white without conspicuous stripes or bands. Snout red, color continuing until pre-operculum. Nape reddish. Silver white line at an angle of about 20° to the horizontal axis of body from nostril to eye, line continues along margin of the orbit decreasing in width posteriorly. Scales above lateral line on body with red margins, but less conspicuous on caudal peduncle. Barbels white with rosy tips. Inter-radial tissue of D1 red between 2 nd and 3 rd rays, translucent between other rays ( Fig. 5A ). Second dorsal fin translucent with scattered reddish blotches ( Fig. 5B ). Distal endings of D1 and D2 with a thin black margin, some specimens with a thin white line or few white blotches proximal to the black margin in the anterior dorsal fin. Caudal fin reddish with increasing intensity towards fin tips ( Fig. 5C ). Posterior end of dorsal lobe of caudal fin with a black margin, terminating slightly ventral to the caudal fork. Ventral lobe of caudal fin has a bright white margin at its proximal end, which increases in width towards the tip of the lobe. A brownish blotch or line anterior to the white margin on the ventral lobe of caudal fin ( Fig. 5C ). Anal fin white with a translucent sphere in its center. Pectoral fins translucent. Small red blotches just dorsal of pectoral fin bases. Pelvic fins translucent with white tips.

Coloration in preserved specimens. Coloration of the holotype after preservation in ethanol is shown in Figure 3B . Area dorsal to lateral line pale white; ventral to lateral line red-purplish. All fins pale white, with black margins along anterior dorsal fin, posterior dorsal fin, and upper lobe of caudal fin. Silver-white line from nostril to eye.

Distribution. This species is only known from the northern region of the Davao Gulf in the Philippines ( Fig. 1 ).

Etymology. The name of this species derives from the black margins along both dorsal fins and the dorsal lobe of the caudal fin.

Remarks. The black-margined goatfish Upeneus nigromarginatus , new species, differs from other Upeneus species ( Table 2) in having a deeper body (31.1–34.8% in SL at origin of first dorsal fin), longer pectoral fins (27.7–29.1% in SL), and a shorter snout (7.1–9.0% in SL). Uiblein & Heemstra (2011) compared seven Upeneus species and found body depth at the first dorsal fin never to exceed 30% in SL. The longest pectoral fin (25% in SL) was found in Upeneus francisi and the shortest snout (9.6% in SL) was recorded for Upeneus guttatus ( Uiblein & Heemstra, 2011) . Several of the type specimens of U. nigromarginatus , new species, have two spines in the anal fin ( Fig. 4 ), although one anal spine is diagnostic for Upeneus ( Uiblein & Heemstra, 2011) . All other characteristics justified the classification of the new species to the genus of Upeneus . The presence of palatine and vomerine teeth is diagnostic for Upeneus ( Uiblein & Heemstra, 2011) . Upeneus nigromarginatus , new species, has villiform teeth on the palate and the vomer, but teeth are smaller in size on the latter. Some individuals of Upeneus filifer , completely lack vomerine teeth ( Kim, 2002) and therefore the smaller size of vomerine teeth was not considered a feature supporting separation from the Upeneus genus.

E c o l o g i c a l i n f o r m a t i o n. Specimens of U p e n e u s nigromarginatus , new species, were sold in a market in Panabo City by a vendor, who introduced me to the fisherman who caught the fish. An interview with the fisherman revealed that these fishes were caught with a gill net (mesh size 2 inches) at a depth of 40–80 m approximately at the coordinates 7°14ʹ32ʺN, 125°40ʹ17ʺE. The net was set at 0400 h of 26 June 2012 and then retrieved an hour later. Upeneus nigromarginatus , new species, was caught together with Upeneus vittatus ( Forsskål, 1775) , Polydactylus longipes Motomura, Okamoto, Iwatsuki, 2001 , and Rexea bengalensis Alcock, 1894 . Upeneus nigromarginatus , new species, is a relatively uncommon species, evidenced by the few individuals which have been caught by fishermen living along the shores of the Lasang River estuary. Anecdotal evidence suggested that fishermen from the northern villages in Samal Island (Davao Gulf) may have caught specimens of this species (pers. comm. N. Gallarda), but a 2-year survey conducted at local fish markets in Samal Island did not reveal other specimens of U. nigromarginatus , new species ( Bos & Gumanao, 2012).

Genetic comparison. The COI fragments of 34 goatfishes provided, after alignment and trimming to equal length, 581 nucleotides for analysis with 208 variable characters. The phylogenetic tree resulting from the Maximum Likelihood construction is shown in Fig. 6 . All specimens formed monophyletic sub-clades with their conspecifics with bootstrap values of ≥74% with only Parupeneus barberinus showing a lower bootstrap value. The five specimens of U. nigromarginatus , new species, were positioned within the monophyletic clade of Upeneus and formed a sub-clade with a bootstrap value of 97%.

A second sub-clade consisted of 10 specimens representing U. japonicus , U. margarethae , U. pori , and U. tragula was well supported with a bootstrap value of 77%. A third subclade included 10 specimens representing U. mascareinsis , U. moluccensis , U. sulphureus , and U. vittatus was supported with a bootstrap value of 57%. Three specimens representing U. parvus formed a fourth sub-clade with a bootstrap value of 99%.

Figures

Fig. 3. A, Upeneus nigromarginatus, new species, holotype, RMNH.PISC.37991, fresh specimen; B, holotype after 4 months in ethanol, SL 196 mm.

Fig. 4. Upeneus nigromarginatus, new species, paratype, RMNH. PISC.36423, anal fin with two spines and six soft rays.White arrow points at short, thin first spine.

Fig. 5. Selected fins of fresh specimen of Upeneus nigromarginatus, new species, holotype,RMNH PISC.37991 (not to scale);A, anterior dorsal fin; B, posterior dorsal fin; C, caudal fin.

Fig. 1. Map of the Philippines archipelago with Davao Gulf in the South-East of Mindanao Island.

Fig. 6. Maximum likelihood phylogeny of representatives of the genus Upeneus (Mullidae). Species names are accompanied by GenBank association numbers, except for those specimens analysed during the ‘present study’ (method validation) and specimens of Upeneus nigromarginatus, new species (RMNH collection numbers). Representatives of the genus Parupeneus were used as an outgroup. Numbers at nodes represent maximum parsimony bootstrap proportions.