Euchiloglanis davidi (Sauvage)

Zhou, Wei, Li, Xu & Thomson, Alfred W., 2011, Two new species of the Glyptosternine catfish genus Euchiloglanis (Teleostei: Sisoridae) from southwest China with redescriptions of E. davidi and E. kishinouyei, Zootaxa 2871, pp. 1-18 : 2-8

Euchiloglanis davidi (Sauvage)

( Fig. 1 , Fig. 2 A, Fig. 3 A)

Chimarrhiththys davidi: Sauvage, 1874: 332 –333 (Yao-Tchy, Tibet, [=Yao-Ji, Baoxing County, Sichuan] China) [Qingyi-Jiang drainage]; Regan, 1905 (in part): 183 (Eastern Tibet).

Euchiloglanis davidi: Norman, 1925 (in part): 574 (Eastern Tibet); Hora & Silas, 1952 (in part): 17 (Eastern Tibet, Yunnan and Szechwan); Chu, 1979: 77 (Qingyi-Jiang, Sichuan) [Qingyi-Jiang drainage]; Chu, 1981: 26–27 (Baoxing, Sichuan) [Qingyi-Jiang drainage]; Ding, 1994 (in part): 484–486 (Baoxing and Yaan, Sichuan) [Qingyi-Jiang drainage], (Danba and Ermei, Sichuan) [Dadu-He drainage]; Chu & Mo, 1999: 160–162 (Baoxing, Sichuan) [Qingyi-Jiang drainage]; Guo et al., 2004a (in part): 261 (Baoxing, Tianquan, and Yaan, Sichuan) [Qingyi-Jiang drainage], (Rangtang, Luding, and Maerkang, Sichuan) [Dadu-He drainage]; Guo et al., 2004b (in part): 1588 (Baoxing, Sichuan) [Qingyi-Jiang drainage]; Guo et al., 2005: 348 (Baoxing, Sichuan) [Qingyi-Jiang drainage]; Guo et al., 2007 (in part): 58 (Baoxing and Yaan, Sichuan) [Qingyi-Jiang drainage], (Luding, Sichuan) [Dadu-He drainage].

Coraglanis kishinouyei: Wu & Chen, 1979 (in part): 293 (Banma, Qinhai) [Dadu-He drainage].

Euchiloglanis kishunouyei: Ding, 1994 (in part): 487–489 (Lushan and Yaan, Sichuan) [Qingyi-Jiang drainage], (Danba, Kangding, and Ermei, Sichuan) [Dadu-He drainage]; Guo et al., 2004a (in part): 261 (Baoxing, Tianquan, and Yaan, Sichuan) [Qingyi-Jiang drainage], (Rangtang, Luding, and Maerkang, Sichuan) [Dadu-He drainage]; Guo et al., 2004b (in part): 1588 (Tianquan, Sichuan) [Qingyi-Jiang drainage]; Peng et al., 2004 (in part): 981 (Tianquan, Sichuan) [Qingyi- Jiang drainage]; Guo et al., 2007 (in part): 58 (Tianquan, Sichuan) [Qingyi-Jiang drainage].

Exostoma davidi: Günther, 1896 (in part): 210 (River Ya [now Qingyi-Jiang]).

Glyptosternum davidi: Hora, 1923 (in part): 37 (Eastern Tibet and adjoining parts of China).

Material examined. All from Qingyi-Jiang: Lectotype: BMNH 1923.3.13.1, 1 ex. 117.5 mm SL, Yao-Tchy, Tibet, China, now Yao-Ji, 30°41’ 53.55’’ N, 102°44’48.34’’ E, Baoxing Co., Sichuan Prov., China; Paralectotypes: MNHN 0000-6273, 3 ex., and MNHN 0000-6274, 3 ex., same data a lectotype; KIZ 795578, 795580-81, 795585- 87, 795590, 795594, 795596-97, 10 ex., 104.2–153.8 mm SL, Yanjing, 30°32’02.37’’ N, 102°54’46.82’’ E, 30.5 km from Yao-Ji in lower reaches of Qingyi-Jiang, Baoxing Co., Sichuan Prov., China; UF 177380, 2 ex., 75.4–78.3 mm SL and SWFC 200204013-24, 200204032-40, 200505004, 22 ex., 66.0–166.0 mm SL, Muping, 30° 22’ 39.96’ N, 102° 48’ 53.52” E, 37.1 km from Yao-Ji in lower reaches of the Qingyi-Jiang, Baoxing Co., Sichuan Prov., China; SWFC, 200204112-21, 10 ex., 75.0–155.0 mm SL, Chengxiang, 30°04’13.28’’N, 102°45’03.85’’ E, Tianquan Co., Sichuan Prov., China.

Diagnosis. Euchiloglanis davidi differs from E. longibarbatus n. sp. by having a pointed maxillary barbel, not elongated as a thread, with the tip reaching only to the gill opening ( Fig. 2 A) (vs. the maxillary barbel elongated as a thread, with the tip reaching posteriorly beyond the gill opening, Fig. 2 C). Euchiloglanis davidi differs from E. longibarbatus n. sp. and E. kishinouyei by having a median indentation in the premaxillary tooth band ( Fig. 3 A) (vs. E. longibarbatus with three indentations in the premaxillary tooth band, one in the middle and two at the sides, Fig. 3 C; E. kishinouyei without indentations, Fig. 3 B). It differs from E. kishinouyei , E. longus n. sp., and E. longibarbatus n. sp. by having the length of the pectoral fin equal to 90.5–117.1% (vs. 75.5–89.6, 78.4–89.5, and 71.2–89.9% respectively) of distance between insertions of pectoral and pelvic fins. Euchiloglanis davidi further differs from E. kishinouyei and E. longibarbatus n. sp. by having the distance between the insertion of the pelvicfin and the anus being equal to 100.0–125.0% (vs. 81.5–97.5 and 75.5–92.2% respectively) of distance between the insertions of the pectoral and the pelvic fins. It further differs from E. longus n. sp. by having the caudal peduncle depth being equal to 7.1–9.7% (vs. 3.4–5.5%) of the standard length and 29.3–46.2% (vs. 14.1–27.0%) of the length of caudal peduncle. Euchiloglanis davidi differs from E. dorsoarcus and E. phongthoensis by having the anus located midway between the pelvic-fin insertion and the anal-fin origin (vs. the distance from the anus to pelvic-fin insertion equal to about 50% of the distance from the anus to the anal-fin origin).

Description. Morphometric and meristic data are in Table 1. Head compressed and snout broadly rounded when viewed dorsally. Eyes small and embedded in skin, located on dorsal surface of head; distance from pupil to tip of snout longer than to dorsal corner of gill opening. Barbels flattened, in four pairs. Nasal barbel with small flap of thin skin fringing posterior margin, not reaching or reaching to anterior margin of orbital. Maxillary barbel with small flap of thin skin, not elongated as a thread ( Fig. 4 A), reaching to gill opening. Origin of inner mandibular barbel close to ventromedial line. Outer mandibular barbel almost reaching pectoral-fin origin.

Mouth inferior and transverse. Anterior margin of premaxillary tooth band exposed when mouth closed. Oral teeth conical and pointed, arranged irregularly and embedded in skin. Premaxillary tooth band crescent-shaped with a median indentation, depth of which increases slightly with growth. Lateral edges of premaxillary tooth band extend posteriorly ( Fig. 5 A). Gill opening extends from posttemporal region to base of first pectoral fin element. Post-labial groove interrupted, ending at base of inner mandibular barbel. Lower lip connected to base of maxillary barbel by skin flap, without sulcus between them.

Dorsal profile rising gradually from tip of snout to origin of dorsal fin, then gradually sloping ventrally to end of caudal peduncle. Body gradually compressed behind origin of adipose fin. Surface of abdomen flattened. Oral region and anterior part of abdomen with dense papillae, gradually decreasing posteriorly.

Dorsal fin located at point through anterior third of body. Distance of dorsal-fin origin to tip of snout longer than distance from dorsal-fin origin to adipose-fin origin. Dorsal fin without spine, distal margin truncate. Tip of last dorsal-fin ray extending posteriorly beyond vertical through pelvic-fin insertion when depressed. Adipose-fin not connected with caudal-fin base, posterior end concave and free. Origin of adipose fin anterior or posterior to vertical through tip of pelvic-fin rays. Adipose-fin base shorter than predorsal length. Distance from origin of anal fin to base of caudal fin longer than distance from anal-fin origin to pelvic-fin origin. Pectoral fin usually extending to pelvic-fin origin. Distance from pelvic-fin origin to anal-fin origin about equal to or longer than distance from pelvic-fin origin to pectoral-fin origin. Pelvic fin reaching posteriorly beyond anus. Anus located midway between pelvic-fin insertion and anal-fin origin. Caudal fin truncate. Lateral line complete, mid-lateral and distinct.

Coloration in fresh specimens. According to collecting records, green-yellow on dorsal surface, milk-white on abdomen. Dorsal fin green-yellow with a lighter medial band, becoming narrow with growth. Pectoral and pelvic fins gray-black with lighter colour around distal edge. Caudal fin gray-black with a small yellow patch in the middle.

Distribution. Known from the Dadu-He and Qingyi-Jiang (branches of the Min-Jiang, Yangtze basin, China) ( Fig. 4 ).

Habitat and ecology. Euchiloglanis davidi has been collected from medium sized rivers with stony or rock substrate. Euchiloglanis davidi is found in rapid flow and creeps along the substrate. Dissecting their intestine indicates that they feed mainly on aquatic insects and their larvae. According to villagers, adults spawn in apertures of the river bottom in May to June and the eggs are viscous.

E. davidi E. kishinouyei

Locality Sichuan: Baoxing: Sichuan: Dujiangyan: Yingxiu Yanjing & Muping

Number specimens 44 Neotype 7

Dorsal-fin rays i, 5 i, 5 i, 5-6

Pectoral-fin rays i, 12–13 i, 12 i, 11–13

Pelvic-fin rays i, 5 i, 5 i, 5

Chimarrhiththys davidi: Regan, 1905 (in part): 183 (Eastern Tibet).

Exostoma davidi: Günther in Pratt, 1892: 245 (Min River [=Min-Jiang], Sze Chuen [=Sichuan]) [Min-Jiang drainage]. Euchiloglanis davidi: Norman, 1925 (in part): 574 (Eastern Tibet); Hora & Silas, 1952 (in part): 17 (Eastern Tibet, Yunnan and Szechwan [Sichuan]); Ding, 1994 (in part): 484–486 (Guanxian [=Dujiangyan], Sichuan) [Min-Jiang drainage]; Guo et al., 2004a (in part): 261 (Guanxian [=Dujiangyan], Wenchuan, Maoxian, Heishui, and Lixian, Sichuan) [Min-Jiang drainage]; Peng et al., 2004: 981 (Dujiangyan [=Dujiangyan], Sichuan) [Min-Jiang drainage]; Guo et al., 2007 (in part): 58 (Maoxian and Wenchuan, Sichuan) [Min-Jiang drainage].

Euchiloglanis kishinouyei: Kimura, 1934: 178 –180 (Kwan-hsien [Guanxian], Szechwan [Sichuan] Prov., China) [Min-Jiang drainage]; Ding, 1994 (in part): 487–489 (Guanxian [=Dujiangyan], Sichuan) [Min-Jiang drainage]; Chu & Mo, 1999 (in part): 162–163 (Guanxian, Sichuan) [Min-Jiang drainage]; Guo et al., 2004a (in part): 261 (Guanxian [=Dujiangyan], Wenchuan, Maoxian, Heishui, and Lixian, Sichuan) [Min-Jiang drainage]; Peng et al., 2004 (in part): 981 (Wenchuan, Sichuan) [Min-Jiang drainage]; Guo et al., 2007 (in part): 58 (Wenchuan, Sichuan) [Min-Jiang drainage].

Glyptosternum davidi: Hora, 1923 (in part): 37 (Eastern Tibet and adjoining parts of China).

Coraglanis kishinouyei: Hora & Silas, 1952: 12 (Chengtu or Kiating, Szechwan [Sichuan], China) [Min-Jiang drainage]; Chu, 1979 (in part): 77 (Sichuan)[upper Min-Jiang only].

Material examined. All from Min-Jiang: Neotype: SWFC 200505068, 135.3 mm SL, Yingxiu, 31°06’54.86’’ N, 103°28’59.19’’ E, Dujiangyan City (formerly Kwan-hsien or Guanxian Co.), Sichuan Prov., China; UF 177381, 2 ex., 121.8–123.6 mm SL, SWFC 200505065-67, SWFC 200505069-70, 5 ex., 120.4–134.6 mm SL, all same data as neotype.

Diagnosis. Euchiloglanis kishinouyei differs from E. longibarbatus by having a pointed maxillary barbel, not elongated as a thread, with the tip reaching only to the gill opening ( Fig. 2 B) (vs. maxillary barbel elongated as a thread, with tip reaching posteriorly beyond gill opening, Fig. 2 C). Euchiloglanis kishinouyei differs from E. davidi , E. longibarbatus n. sp. and E. longus n. sp. by lacking indentations in premaxillary tooth band ( Fig. 3 B) (vs. with indentations, Fig. 3 A, C, D). It differs from E. davidi by having the length of the pectoral fin being equal to 75.5–89.6% (vs. 90.5–117.1%) of distance between insertions of pectoral and pelvic fins and further differs from E. davidi and E. longus by having the distance between insertion of pelvic-fin and origin of anus being equal to 81.5–97.5% (vs. 100.0–125.0 and 108.9–140.6% respectively) of distance between insertions of pectoral and pelvic fins. Euchiloglanis kishinouyei differs from E. dorsoarcus and E. phongthoensis by having the anus located midway between the pelvic-fin insertion and the anal-fin origin (vs. the distance from the anus to pelvic-fin insertion equal to about 50% of the distance from the anus to the anal-fin origin).

Description. Morphometric and meristic data are in Table 1. Head compressed and snout broadly rounded when viewed dorsally. Eyes small and embedded in skin, located on dorsal surface of head; distance from pupil to tip of snout longer than to dorsal corner of gill opening. Barbels flattened, in four pairs. Nasal barbel with small flap of thin skin fringing posterior margin, not reaching or reaching to anterior margin of orbital. Maxillary barbel with small flap of thin skin, not elongated as a thread ( Fig. 4 B), reaching to gill opening. Origin of inner mandibular barbel close to ventromedial line. Outer mandibular barbel almost reaching pectoral-fin origin.

Mouth inferior and transverse. Anterior margin of premaxillary tooth band exposed when mouth closed. Oral teeth conical and pointed, arranged irregularly and embedded in skin. Premaxillary tooth band crescent-shaped without any indentations. Lateral edges of premaxillary tooth band extend posteriorly ( Fig. 5 B). Gill opening extends from posttemporal region to base of first pectoral fin element. Post-labial groove interrupted, ending at base of inner mandibular barbel. Lower lip connected to base of maxillary barbel by skin flap, without sulcus between them.

Dorsal profile rising gradually from tip of snout to origin of dorsal fin, then gradually sloping ventrally to end of caudal peduncle. Body gradually compressed behind origin of adipose fin. Surface of abdomen flattened. Oral region and anterior part of abdomen with dense papillae, gradually decreasing posteriorly.

Dorsal fin located at point through anterior third of body. Distance of dorsal-fin origin to tip of snout longer than distance from dorsal-fin origin to adipose-fin origin. Dorsal fin without spine, distal margin truncate. Tip of last dorsal-fin ray extending to or extending posteriorly beyond vertical through pelvic-fin insertion when depressed. Adipose-fin not connected with caudal-fin base, posterior end concave and free. Origin of adipose fin anterior or posterior to vertical through tip of pelvic-fin rays. Adipose-fin base shorter than predorsal length. Distance from origin of anal fin to base of caudal fin longer than distance from anal-fin origin to pelvic-fin origin. Pectoral fin not extending to pelvic-fin origin. Distance from pelvic-fin origin to anal-fin origin shorter than distance from pelvic-fin origin to pectoral-fin origin. Pelvic fin reaching posteriorly beyond anus. Anus located midway between pelvic-fin insertion and anal-fin origin. Caudal fin truncate. Lateral line complete, mid-lateral and distinct.

Coloration in fresh specimens. According to collecting records, green-yellow on dorsal surface, milk-white on abdomen. Dorsal fin green-yellow with a lighter medial band, becoming narrow with growth. Pectoral and pelvic fins gray-black with lighter color around distal edge. Caudal fin gray-black with a small yellow patch in the middle.

Distribution. Known only from the upper Min-Jiang (Yangtze River basin, China) ( Fig. 4 ).

Habitat and ecology. The reaches where specimens were collected are floodplain, about 30 m width with sand and rock substrate. Because rainfall concentrates in May to August in the area of Dujiangyan City, the floodwater falls back rapidly and frequently. In the rainy season the current is turbid and rapid. Euchiloglanis kishinouyei feeds mainly on aquatic insects and their larvae. According to villagers, adults spawn in apertures of the river bottom in May to June and the eggs are viscous.

Figures

FIGURE 1. Euchiloglanis davidi, A, KIZ 795586, 153.8 mm SL; Yanjing, Baoxing Co., Sichuan Prov.; lateral view. B, SWFC 200204112, 155.0 mm SL; Muping, Baoxing Co., Sichuan Prov., China; dorsal, lateral and ventral views. Scale bar = 10 mm.

FIGURE 2. Ventral view of maxillary barbel. A, B & D, maxillary barbel pointed, not elongated as a thread [A, Euchiloglanis davidi, topotype, SWFC 200204018, 111.0 mm SL, Muping, Baoxing Co., Sichuan Prov., China; B, E. kishinouyei, topotype, SWFC 200505071, 124.4 mm SL, Guankou, Dujiangyan City (formerly Kwan-hsien or Guanxian Co.), Sichuan Prov., China; D, E. longus, SWFC 200311007, holotype, 135.2 mm SL, Mola, Jingdong Co., Yunnan Prov., China]; C, maxillary barbel slen- der, pointed, elongated as a thread (E. longibarbatus, SWFC 200505059, paratype, 175.2 mm SL, Sigongli, Yajiang Co., Sichuan Prov., China).

FIGURE 3. Ventral view of premaxillary tooth band. A & D, premaxillary band with a median indentation (A, Euchiloglanis davidi, SWFC 200204018, 111.0 mm SL, Muping, Baoxing Co., Sichuan Prov., China; D, E. longus, SWFC 200311001, paratypes, 221.9 mm SL, Mola, Jingdong Co., Yunnan Prov., China); B, premaxillary band without indentation (E. kishinouyei, SWFC 200505071, topotype, 124.4 mm SL, Guankou, Dujiangyan City [formerly Kwan-hsien or Guanxian Co.], Sichuan Prov., China); C, premaxillary band with three indentations (E. longibarbatus, SWFC 200505059, paratype, 175.2 mm SL, Sigongli, Yajiang Co., Sichuan Prov., China).

FIGURE 4. Collecting localities of examined specimens of Euchiloglanis. A symbol may represent several adjacent localities. 1, Min-Jiang, upper tributary of Yangtze River; 2, Qingyi-Jiang, branch of Dadu-He; 3, Dadu-He, branch of Min-Jiang; 4, Yalong-Jiang, upper tributary of Yangtze River; 5, Jinsha-Jiang, upper Yangtze River; 6, Jaling-Jiang, branch of Yangtze River; 7, Wu-Jang, branch of Yangtze River; 8, Yuan-Jiang, the upper Red River; 9, Lixian-Jiang, branch of Red River; 10, Mekong River; 11, Salween River.

FIGURE 5. Euchiloglanis kishinouyei, SWFC 200505068, neotype, 135.3 mm SL; Yingxiu, Dujiangyan City (formally called Kwan-hsien or Guanxian Co.), Sichuan Prov., China. Dorsal, lateral and ventral views. Scale bar = 10 mm.