Valenciennea wardii (Playfair in Playfair et Günther, 1867 )

Choi, Si-Won, Myoung, Se Hun, Bae, Chang-Soo, Woo, Min-Su, Kim, Yun-Bae & Park, Joo Myun, 2025, Northernmost record of Valenciennea wardii (Actinopterygii, Gobiiformes, Gobiidae) from Ulleung Island, Northwest Pacific, Acta Ichthyologica et Piscatoria 55, pp. 237-246 : 237-246

Valenciennea wardii (Playfair in Playfair et Günther, 1867)

English common name: Ward’s sleeper New Korean name: 갈색띠복기망둑 [gal-saeg-tti-bok-gi-mang-duk] Fig. 2 ; Table 1

Valenciennea wardii (Playfair in Playfair et Günther, 1867). — Hoese and Larson 1994: 63 ( Japan, Vietnam, Thailand, Maldives, Sudan, Western Australia, Gulf of Aden, Egypt). — Randall and Egmond 1994: 65 ( Seychelles). — Allen et al. 2003: 152 ( Papua New Guinea). — Allen and Adrim 2003: 61 ( Indonesia). — Randall 2005: 558 ( New Caledonia). — Nakabo 2013: 1508 ( Japan). — Choi et al. 2013: 445 ( Micronesia). — Lin et al. 2016: 75 (East China Sea). — Prokofiev 2016: 814 ( Vietnam). — Shea and To 2018: 3 ( Hong Kong). — Fricke et al. 2019: 292 ( Papua New Guinea). — Ragul et al. 2024: 63 ( India).

Specimen observed.

Voucher number NIFS_FRRC_2 , standard length 26.44 mm, collected from eastern coast of Ulleung Island ( 37°29′01″N, 130°47′54″E), at a depth of 24 m, bottom water temperature 21°C, using a hand net, 11 November 2024 .

Morphological description.

Body slender and elongated, tapering towards caudal region. Eyes positioned close together across dorsal midline. Snout protruding, with tip of upper jaw extending beyond lower jaw. Posterior end of maxilla reaching midpoint of eye. Gill opening extending below middle of preopercle. Body covered with ctenoid scales, with scaleless pectoral fin base. Dorsal fins separated; first dorsal fin with spines only, and second dorsal fin comprising one spine and several soft rays. Spine tips of dorsal fin soft and curved backward. Dorsal fin margin rounded. Second dorsal fin origin located anterior to anal fin origin. Tip of pectoral fin reaching anal fin origin. Caudal fin rounded with a tapered tip (Fig. 2 C ). Pelvic fins separated (Fig. 2 D ). Meristic counts and body part measurements of Valenciennea wardii shown in Table 1 .

Coloration.

Head light brown, with diagonal reddish stripe crossing pupil. Yellow stripe running obliquely from upper jaw across posterior edge of preopercle to gill region, bordered by black-edged blue stripe above. Body light grey, bearing three dark brown transverse bands that widen posteriorly. Black blotch extending from dorsal fin membrane to dorsal surface of caudal peduncle, positioned between second and third brown transverse bands and near posterior end of caudal peduncle. Round black spot present between fourth and sixth spines of first dorsal fin, bordered with white. Dorsal fin margin white. White blotches extending from body to midsection of dorsal fin membrane. Anal fins with white and light orange edges bordered with black. Pectoral fin membranes transparent with light brown rays. Pelvic fins entirely white, with faint yellowish tinge in middle. Caudal fin with prominent black spot near upper tip and faint dark yellow spot at base. Caudal fin base white, transitioning to yellow towards posterior. Tips of soft rays from upper to middle sections of caudal fin were white (Fig. 2 ).

Molecular analysis.

A 596 bp mtDNA COI sequence was obtained and compared to 10 species of the genus Valenciennea ( V. wardii , V. sexguttata , V. strigata , V. helsdingenii , V. parva , V. muralis , V. longipinnis , V. puellaris , V. persica , and V. immaculata ) registered in the NCBI and BOLD databases. V. wardii collected from the Ulleung Island in the East Sea (otherwise known as the Sea of Japan) showed a genetic distance of 0–0.012 from individuals from Taiwan, the South China Sea, and Sri Lanka, and a distance of 0.044 from an individual from the Philippines. The genetic distance from other Valenciennea species ranged between 0.169 and 0.244, confirming species-level differentiation (Fig. 3 ).

Seawater temperature.

In 2024, the highest water temperature (28.6°C) was recorded in August, while the lowest (11.8°C) was recorded in February. The annual mean water temperature in 2012, as well as the average temperatures during the summer (August) and winter (February) season were 1.9°C, 1.2°C, and 2.2°C higher compared to those in 2012, respectively (Fig. 4 ). Water temperature has shown an increasing trend over the past decade (2012–2024).

Figures

Figure 2. Valenciennea wardii, NIFS _ FRRC _ 2 (26.44 mm SL), the Ulleung Island, Republic of Korea, November 11, 2024. A in-situ underwater image; B dorsal view; C lateral view; D ventral view.

Figure 3. Neighbor joining tree based on partial mitochondrial DNA COI region, showing the relationships among 10 species of genus Valenciennea and 1 outgroup Pherallodus indicus. The tree was constructed using the Kimura 2 - parameter model and 1000 bootstrap replications The parentheses indicate the NCBI accession number while the superscript indicates sampling site of Valenciennea wardii. The bottom bar indicates a genetic distance of 0.05.

Figure 4. Long-term changes (2012–2014) in monthly mean sea surface temperature around the Ulleung Island.