We describe the morphological characteristics of two morids, Gadella jordani and Physiculus japonicus, belonging to the order Gadiformes, based on Korean specimens collected from the Korean ocean. Two specimens of Gadella jordani was first collected from Jeju Island, Korea and the East Sea, Korea, in 2013-2014. This species is characterized by 8, 67-69 dorsal fin rays, 66-71 anal fin rays, 5+13 gill rakers, no barbel on the lower jaw, no vomerine teeth, and a ventral luminous organ closer to the anus than to the interventral line. We described it as the first record to the Korean fish fauna, and proposed the new Korean name “Min-su-yeom-dae-gu-sok” for the genus Gadella, and “Min-su-yeom-dae-gu” for the species G. jordani. Physiculus japonicus was first reported by Koh and Moon in the year 1999 based on a single specimen in Korea. However, no study has been attempted to describe the morphological characteristics in Korea since then. In 2013-2014, three specimens of P. japonicus was collected from Jeju Island, Korea and the East Sea, Korea, and we redescribe P. japonicus in detail. This species is characterized by 9-10, 63-64 dorsal fin rays, 70-73 anal fin rays, 3+7-8 gill rakers, a short barbel on the lower jaw, and a ventral luminous organ equidistant between the interventral line and the anus.
The family Moridae in the order Gadiformes comprises 107 species of 18 genera worldwide (Eschmeyer and Fong, 2015). In Japan, 17 species of 8 genera are currently known (Nakabo, 2013), and three species, each belonging to different genera, are found in Korea (Kim, 2011) including
The genus
In Korea,
Two specimens of
The molecular identification of
Diagnosis. Body elongated and compressed; snout broad, obtusely rounded; teeth variable; no vomerine teeth; no barbel on lower jaw; pelvic fins with two outermost rays filamentous; ventral luminous organ in anterior to anus; scales small, cycloid, covering entire body but not on snout; otoliths spindle shaped, inside straight (Lowe, 1843; Paulin, 1989).
Remarks. In the genus
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[Table 1.] Comparison of counts and measurements of Gadella jordani
Comparison of counts and measurements of Gadella jordani
Material examined. One specimen, 281.0 mm in standard length (SL), collected by bottom trawl net, at 129-148 m depth, Hupo, Uljin, East Sea, Korea (36°43.30′N, 129°32.81′ E), 5 May 2013, ESFRI 1106; one specimen, 119.7 mm SL, collected by bottom trawl net, northeast coast of Jeju Island, Korea, 27 Oct 2014, PKU 11461.
Comparative material examined. One specimen, 77.0 mm SL, collected by trawl net, Suruga Bay, Japan (35°00.194′N, 138°22.497′E), 27 Nov 2013, MSM-15-13.
Description. Counts and measurements as shown in Table 1. Body slim and elongated (Fig. 1). Tail compressed; very narrow caudal peduncle. No V-shaped ridge on top of skull; dorsal margin of head slightly sloping; snout short and rounded; mouth large and terminal; posterior tip of maxilla reaching to posterior margin of eye; no barbel on lower jaw; teeth villiform, small, equal size, arranged in 3-5 rows on both jaws; no vomerine teeth; eyes small; interorbital space wider than eye diameter; two pairs of nostrils, circular shape. Gill slit large; posterior margin of opercle not reaching to origin of pectoral fin. Lateral line extending from opercular flap to base of caudal fin. Fins lack spines; origin of first dorsal fin vertically above upper end of gill opening; first dorsal fin ray not elongated; origin of second dorsal fin begins vertically above base of anal fin; second dorsal fin and anal fin same in height; posterior margin of pectoral fin extending until base of anal fin; pelvic fin with outermost two rays filamentous, beginning under lower base of pectoral fin; anal fin not notched; caudal fin slightly rounded, separated dorsal and anal fin rays. Ventral luminous organ small and placed closer to anus than to interventral line. Anus anterior to origin of anal fin. Head and body covered with cycloid scales, except for lower position of snout, branchiostegal membranes, vertical fin membranes, ventral luminous organ (ESFRI 1106, PKU 11461).
Color. When fresh: body reddish-brown dorsally and bluish ventrally, undersides of head and abdomen bluishblack; lips, tip of tongue, branchiostegal membranes, and gill rakers blackish; all fins transparent, with dark spots on dorsal and anal fin membranes; posterior margin of caudal fin dark brown (Fig. 1). In ethanol: body yellowish-brown; undersides of head and abdomen blackish; lower jaw blackish; all fins transparent.
Distribution. East Sea (Uljin) and Jeju Island, Korea (present study); Japan (Okamoto et al., 2010); China (Chinese Academy of Fishery Science, 2007); Taiwan (Shao, 1997); Australia (Hoese et al., 2006); Fiji (Seeto and Baldwin, 2010).
Remarks. The examined specimens were identified as
[Table 2.] Comparison of counts and measurements of Physiculus japonicus
Comparison of counts and measurements of Physiculus japonicus
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Physiculus japonicus
Material examined. One specimen, 362.0 mm SL, collected by set net, Daejin, Goseong, East Sea, Korea, 12 Feb 2013, ESFRI 907; one specimen, 374.5 mm SL, collected by set net, Sokcho, East Sea, Korea, 14 Mar 2013, PKU 8358; one specimen, 269.3 mm SL, collected by trawl net, Jeju Island, Korea, 10 Mar 2014, PKU 10366.
Description. Counts and measurements shown in Table 2. Body slim and elongated (Fig. 2). Narrow caudal peduncle; tail compressed; head and abdominal region are laterally compressed. Head moderately large and anterior slightly vertically depressed; no V-shaped ridge on top of the skull; snout rounded and protrudes slightly beyond the upper jaw; mouth large and subterminal; posterior tip of maxilla reaching to posterior margin of the eye; short barbel on lower jaw, shorter than orbit diameter; teeth conical, small, arranged in 4-5 rows on both jaws; outer premaxillary teeth somewhat larger than inner; no vomerine teeth; eyes moderately small; interorbital space wider than eye diameter; two pairs of nostrils, circular shape. Posterior margin of opercle not reaching to origin of pectoral fin; lateral line extending from opercular flap to middle of the second dorsal fin; fins lack spines; origin of the first dorsal fin posterior to and vertically above base of pectoral fin; first dorsal fin rays not elongated; origin of second dorsal fin posterior to margin of pectoral fin; pelvic fin begins anterior to base of pectoral fin, outermost two rays filamentous; anal fin not notched. Ventral luminous organ moderately large, generally positioned midway between interventral line and anus; caudal fin slightly rounded, separated in the dorsal and anal fin rays. Head and body covered with cycloid scales, except for the suborbital region, lower position of snout, branchiostegal membranes, vertical fin membranes, and ventral luminous organ (Table 2, Figs. 2, 3).
Color. When fresh: body reddish-brown; undersides of head and abdomen bluish-black. Lips dark brown; branchiostegal membranes and gill rakers blackish; all fins reddish-brown, posterior margins of dorsal, anal, and caudal fins blackish (Fig. 2). In ethanol: body brownish-yellow; undersides of head and abdomen blackish; all fins are pale.
Distribution. East Sea (Sokcho and Goseong) and Jeju Island, Korea (present study; Koh and Moon, 2003); Japan (Cohen et al., 1990); China (Chinese Academy of Fishery Science, 2007); Taiwan (Shen et al., 1993).
Remarks. As shown in Table 2, the morphological characteristics of these specimens in the present study correspond well with those of the previous studies (Paulin, 1989; Koh and Moon, 2003; Yu and Ho, 2012). In Japan, six species of the genus
Korean name:1*민수염대구속, 2*민수염대구