Priolepis profunda (Weber, 1909)

Fujiwara, Kyoji, Psomadakis, Peter N., Swe, Thet Yu Yu & Motomura, Hiroyuki, 2022, First records of the two gobies, Cryptocentrus shigensis and Priolepis profunda (Actinopterygii: Gobiiformes: Gobiidae), from the Andaman Sea, Acta Ichthyologica et Piscatoria 52 (1), pp. 21-27 : 21

Priolepis profunda (Weber, 1909)

[English name: narrowbar reef goby] Figs 2 and 3

Material examined.

SAIAB 208454, male, 24.4 mm SL, station 143 (11°01′34″N, 97°56′32″E), north of Clara Island , Myanmar, Andaman Sea, Indian Ocean, 59 m depth, R/ V. Dr. Fridtjof Nansen (P. N. Psomadakis), bottom trawl, 25 Sep 2018 .

Description.

Counts and measurements are given in Table 1 and general appearance in Fig. 2 . Body somewhat stout, subcylindrical anteriorly, compressed posteriorly. Anus located just before anal-fin origin. Head relatively large, slightly depressed anteriorly. Snout moderate (slightly shorter than eye diameter), rounded. Eyes large, located dorsolaterally. Interorbital region narrow, flattened. Anterior and posterior nostrils close to each other; former located mid-way between anterior tip of snout and eye; latter located just before orbit, larger than former; both with membranous tube. Mouth terminal, inclined anterodorsally, forming an angle of ca. 60° with body axis. Lower jaw subequal to upper jaw, its posterior tip reaching to vertical through anterior margin of pupil. Upper-jaw tip behind vertical through lower-jaw tip. Both jaws with irregular rows of small, pointed conical teeth, with tip of each slightly incurved posteriorly; teeth in outermost row on jaws more widely spaced and distinctly larger than teeth in inner rows. Gill membranes attached anteriorly to isthmus. Gill opening relatively narrow, anteroventral point extending slightly forward to vertical level of preopercle margin.

Cephalic sensory system. Detailed pattern of cephalic sensory system is given in Figs 3A-C . Head sensory canals pores absent. Head sensory papillae damaged, but following conditions confirmed: 5 transverse papillae rows present on suborbital region; 2 transverse papillae rows present on interorbital region, neither connecting in mid-line, anterior and posterior rows including 2 and 3 papillae, respectively; 2 longitudinal papillae rows present on chin and ventrolateral surface, each papillae row on chin well-spaced anteriorly, becoming gradually closer posteriorly, but not joining.

Scales. Body covered with ctenoid scales, except abdomen (covered with cycloid scales). Pre-dorsal region fully scaled (except just behind 1st dorsal-fin origin), anterior margin of scaled area rounded, reaching vertical through posterior margin of pupil. Pre-pelvic-fin region covered with ca. 6 rows of cycloid scales, anterior margin reaching just behind anteroventral point of gill opening. Entire head region (except for lateral surface of nape) naked. Pectoral-fin base with cycloid scales.

Fins. All dorsal- and anal-fin spines slender, flexible. First dorsal fin squarish, all spines without filamentous tips, 5th spine longest; dorsal-fin origin located just above dorsal origin of pectoral fin. Second dorsal and anal fins relatively short, origin of latter slightly posterior to vertical through 2nd dorsal-fin origin. Pectoral fin long, pointed, middle rays longest, tips reaching just above base of 2nd anal-fin ray. Pelvic fins weakly fused medially with connecting membrane (between ca. 1/5 innermost rays), pelvic frenum absent; posterior tip reaching anus; pelvic-fin origin just below ventral end of pectoral-fin base; all segmented pelvic-fin rays branched. Caudal fin relatively short, with rounded posterior margin.

Coloration.

Based on Fig. 2 . Head and body orange with many narrow white bars, all bars on each side connected mid-dorsally. Four bars on interorbital region; anterior two bars continuous with two bars under eye; posteriormost bar relatively curved posteriorly, more widely spaced from anterior bars. Two bars on postorbital region; former strongly curved, extending from middle of nape to lower edge of preopercle through posterior margin of eye; latter weakly curved, extending from posterior end of head to lower margin of opercle. Eight straight vertical bars along body; two anteriormost below origin and middle of 1st dorsal-fin base, respectively, middle three below origin, middle and posterior end of 2nd dorsal-fin base, respectively, three posteriormost on caudal peduncle (two) and caudal-fin base. All fins orange basally; anterior part of 1st dorsal fin with dark brown smudge; small reddish-orange spots on 2nd dorsal fin and upper part of caudal fin; a single short, pale white bar on pectoral-fin base; caudal fin lacking dark black blotches or bar.

Color in alcohol. Head and body pale brown. All bars visible in fresh specimen retained (pale white with brown edge), but those posteriorly on body somewhat indistinct. All fins translucent white basally, anterior part of 1st dorsal fin and 2nd dorsal-fin base dark brown.

Identification.

The Andaman specimen (SAIAB 208454) agreed well with the detailed description of P. profunda provided by Hoese and Larson (2010), especially as follows: transverse papillae rows present on suborbital region (Fig. 3B ); 6 papillae present on posterior part of interorbital region (Fig. 3A ); anterior margin of pre-dorsal scales reaching to vertical through posterior margin of pupil (Figs 3A and B ); 8 narrow white bars on body (Fig. 2 ).

Distribution.

Priolepis profunda has previously been recorded widely from the western Pacific Ocean (Japan, Philippines, Thailand, Indonesia, Papua New Guinea, and northwestern Australia; Hoese and Larson 2010; Allen and Erdmann 2012; Akihito et al. 2013). Recently, Ramachandran et al. (2020) recorded the species from India, being the first Indian Ocean record. However, because the inclusion of the Andaman Islands within the distributional range of P. profunda by Allen and Erdmann (2012) was not supported by underwater photographs or voucher specimens, the presently reported specimen represents the first reliable record of P. profunda from the Andaman Sea (Myanmar).

Remarks.

In addition to P. profunda , 11 species of Priolepis are known to have transverse papillae rows on the suborbital region [ P. profunda grade sensu Winterbottom and Burridge (1993)] ( Winterbottom and Burridge 1992; Nogawa and Endo 2007; Hoese and Larson 2010; Bogorodsky et al. 2016; Allen et al. 2018; Fujiwara et al. 2020; Koeda et al. 2021). Priolepis profunda and seven of the 11 species also share white bars on the body, although the number and width of the bars in P. profunda are relatively high (8 bars) and distinctly narrow, respectively. Moreover, the combination of squamation on the pre-dorsal region and number of papillae on the interorbital region of P. profunda (see Identification) is unique within the species complex.

Figures

Figure 2. Fresh (A, B) and preserved (C) specimen of Priolepis profunda (SAIAB 208454, male, 24.4 mm SL).

Figure 3. Head of Priolepis profunda (SAIAB 208454, 24.4 mm SL), showing cephalic sensory system. Yellow arrows indicate sensory papilla (A) and papillae rows (B - C). AN and PN indicate anterior and posterior nostrils, respectively. Black arrows indicate anteroventral end of gill opening.