Ophichthus urolophus ( Temminck and Schlegel, 1846 )

Vo, Quang Van, Hibino, Yusuke & Ho, Hsuan-Ching, 2019, Ophiacantha scissionis Lee & Stöhr & Bae & Shin 2019, sp. nov., Zoological Studies (Zool. Stud.) 58 (43), pp. 1-14 : 10-12

Ophichthus urolophus ( Temminck and Schlegel, 1846) ( Fig. 7; Table 3)

Conger urolophus Temminck and Schlegel, 1846: 260 , Pl. 114 (fig. 1) (type locality: Japan).

Ophichthus tsuchidae Jordan and Snyder, 1901: 873, fig. 19 (type locality: Misaki, Japan).

S p e c i m e n s e x a m i n e d: 2 s p e c i m e n s: OIM-E.55788‒89, 384‒ 422 mm TL, collected from LƯƠng SƠn fishing harbour, LƯƠng SƠn Commune, Nha Trang city, Khánh Hòa province, by trawl at 50‒60 m, 8 Aug. 2018, by Q.V. Vo.

Description: Body moderately elongate ( Fig. 7), subcircular to posterior portion of tail, then becoming slightly compressed, its depth at gill openings 22–26 times in TL. Branchial basket slightly expanded. Head 8.3–9.0 in TL. Head and trunk 2.3 in TL. Snout short, broadly rounded when viewed from above and side; underside of snout bisected by a groove. Lower jaw included, its tip reaching to anterior margin of anterior nostril tube. Upper jaw less elongated, rictus well behind a vertical from posterior margin of eye. Eye moderate, situated at anterior margin of upper jaw, 2.6‒2.9 in upper jaw and 7.6–8.3 in head. Anterior nostrils tubular, extending ventrolaterally from snout, reaching below upper lip and chin when directed downward. Posterior nostril a hole above upper lip, covered by a flap that extends well below edge of mouth. A single stout barbel on upper lip at anterior base of posterior nostril on upper lip; no barbel below eye. Dorsal-fin origin at or behind tip of pectoral fin. Median fins low but obvious, ending approximately an eye diameter before the broadly pointed tail tip. Pectoral fins elongate but not lanceolate, the longest rays at mid fin.

Head pores small but apparent. Single median interorbital (frontal) and temporal pores. Supraorbital pores 1 + 3, infraorbital pores 4 + 2, mandibular pores 6‒7, preopercular pores 2, supratemporal pores 3. Faint rows of minute sensory papillae are present along nape, along anterior margin of orbit, and in a horseshoe-shaped pattern around base of anterior nostril. Lateral-line pores apparent; 9 on head, in an arching sequence, 17 before dorsal-fin origin; 56‒57 before anus, 133‒135 in total, the last ca. 2 eye diameters before tail tip.

Teeth moderate, conical, and separated from each other at base. Intermaxillary with 3–5 teeth in a curved row, followed by 11–14 uniserial vomerine teeth, which decrease slightly in size posteriorly. Maxillary teeth uniserial with 17–19 in a row, with an inner row of 5‒6 teeth at front of the posterior nostrils. Mandibular teeth also uniserial, with 21 in a row, decreasing in size posteriorly.

C o lo r a tio n: Wh en f r es h: y e llo w is h -b r o w n dorsally, slightly contrasting with the white throat and belly, extending to the anus. Dorsal fin grayish; anal fin uniformly white. Pectoral fin light grayish. When preserved: yellowish-brown dorsally, slightly contrasting with the white throat and belly, extending to anus. Dorsal fin grayish. Pectoral fin grayish.