Liobagrus kingi Tchang, 1935

Xie, Rui-Xia, 2018, Re-description of the catfish species Liobagrus kingi Tchang, 1935 (Pisces: Amblycipitidae) from the upper Chang-Jiang basin, China, Zootaxa 4476 (1), pp. 69-76 : 70-72

Liobagrus kingi Tchang, 1935

( Fig. 1 )

Liobagrus kingi Tchang, 1935: 95 (Tsingning, Yunnan Province); Chu and Chen, 1990: 169 (Lake Dianchi in Kunming City); Ding, 1994: 472 (Huidong County, Sichuan Province); Chen, 1998: 291 (Lake Dianchi in Haigeng County, Kunming City); Chu et al. 1999: 105 (Kunming City, Fumin and Yongren counties in Yunnan Province).

Diagnosis. A member of the species group of Liobagrus diagnosed by having a serrated posterior margin of the pectoral-fin spine. Liobagrus kingi , together with L. chenghaiensis , is distinguished from all other species of this group by having fewer anal-fin rays (10–12 vs. 13–19) ( Table 1). Liobagrus kingi is distinct from L. chenghaiensis in having a rounded (vs. sub-truncate) caudal fin, vent positioned closer to the anal-fin origin than to the pelvic-fin insertion (vs. equidistant from the pelvic-fin insertion and the anal-fin origin), maxillary barbels not extending to (vs. reaching) the pectoral-fin insertion ( Table 1).

Notes: data from a, Regan (1904); b, Wright and Ng (2008); c, Sun et al. (2013); d, Son et al. (1987); e, Park et al. (2010); f, Kim et al. (2015).

Description. Morphometric data for the holotype and two topotypic specimens are summarized in Table 2. See Figure 1 for general body appearance. Body elongate; anteriorly wide and posteriorly increasingly compressed to caudal fin. Predorsal profile gradually sloping ventrally from dorsal-fin origin to occiput, becoming more convex and abruptly declining from occiput to posterior margin of eye; slope declining with profile becoming slightly convex from posterior margin of eye to snout tip. Ventral profile nearly straight from head to anal-fin origin and progressively sloping upwards along anal-fin base; slightly concave from posterior end of anal-fin base to origin of ventral procurrent caudal-fin rays. Lateral line short with 5–6 pores, midlateral; extending to vertical through, or slightly behind, base of dorsal-fin spine.

Head depressed and broad, much wider than deep. Snout broadly rounded when viewed dorsally and subconical when viewed laterally. Anterior nostril tubular, rim with fleshy flap forming short tube; posterior nostril pore-like and located immediately anterior to eye; rim posteriorly confluent with nasal-barbel base. Eye small, dorso-laterally positioned immediately behind posterior nostril, subcutaneous and ovoid. Interorbital space flattened to slightly convex. Gill membranes narrowly joined at isthmus.

Mouth terminal. Lips thickened and papillated. Jaws covered by lips, upper and lower jaws of equal length. Premaxillary and mandibular toothpads broadly curved with villiform or setiform teeth. Four pairs of barbels; nasal pair small, thread-like, extending beyond posterior edge of eye, but not to pectoral-fin insertion; maxillary pair slender, not reaching pectoral-fin insertion; outer mental pair extending to pectoral-fin insertion, but not reaching posteriormost margin of preoperculum; inner mental barbels nearly half or two-thirds of outer mental-barbel length, approaching gill membrane margin at isthmus, but not pectoral-fin insertion.

Dorsal fin II, 6 (3); origin nearer to snout tip than to adipose-fin origin, above middle pectoral-fin spine or closer to pectoral- than to pelvic-fin insertion; distal edge convex; tip of depressed fin rays not reaching pelvic-fin insertion. Dorsal-fin spine covered by thick skin, straight, with a smooth anterior and posterior margin, nearly half of longest branched dorsal-fin ray, slightly longer than pectoral-fin spine. Adipose fin long at base, low in depth, posteriorly continuous with caudal fin, but with a marked incision at confluence; originating opposite to vent or anterior to vertical through tip of depressed pelvic-fin rays. Pectoral fin I,7 (3), inserted slightly anterior to vertical through posterior margin of operculum, partially covered by opercular membrane; tip of depressed fin extending to middle of dorsal-fin base. Pectoral-fin spine having a smooth anterior and serrated posterior margin, sharp with deep grooves along shaft as well as dorsal-fin spine. Pelvic fin Ỉ, 5 (3), located posterior to vertical through tip of depressed dorsal fin; inserted closer to caudal-fin base than to snout tip; tip of depressed fin rays extending to vent, but not to anal-fin origin. Vent located closer to anal-fin origin than to pelvic-fin insertion. Anal fin with 11 (holotype) or 12 (topotype) rays; origin closer to pelvic-fin insertion than to caudal-fin base; tip of depressed fin rays reaching origin of ventral procurrent caudal-fin rays; longer than dorsal fin in basal length, and shorter than adipose fin in basal length; distal margin rounded. Caudal fin rounded.

Coloration in preservative. In terms of original description, body greyish and marbled with black spots. Dorsal fin yellowish with a medial black band; pectoral fin black basally and yellowish distally; pelvic and anal fins yellowish, marbled with blackish spots; caudal fin black, but with yellowish upper, lower and posterior margins.

Distribution. Known only from the upper Chang-Jiang basin including Lake Dianchi ( Fig. 2 ).

Material examined. Liobagrus kingi : ASIZB 19825 (11673), holotype, 89.7 mm SL, Lake Dianchi , Yunnan Province ; KIZ 1960000611–2, topotypes (2) 67.6–75.9 mm SL.

Figures

FIGURE 1. Lateral (A, D), dorsal (B, E) and ventral (C, F) views of Liobagrus kingi: ASIZB 19825 (11673) (ABC), holotype, 89.7 mm, China, Yunnan Province, Jinning County; KIZ 1960000612 (DEF), 67.6 mm, China, Yunnan Province.

FIGURE 2. Distribution of Liobagrus kingi (*, *) and Liobagrus chenghaiensis (▲) in China. ▲ and ▲, localities of examined specimens; *, historical records (Chen 1998, Chu & Chen 1990, Ding 1994).