Euchiloglanis longibarbatus, Zhou, Wei, Li, Xu & Thomson, Alfred W., 2011

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 : 9-12

Euchiloglanis longibarbatus , n. sp.

( Fig. 2 C, Fig. 3 C, Fig. 6 )

Euchiloglanis davidi: Ding, 1994 (in part): 486 (Jinsha-Jiang and Yalong-Jiang) [Jinsha-Jiang and Yalong-Jiang drainages]; Guo et al., 2004a (in part): 261 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Guo et al., 2004b (in part): 1588 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Peng et al., 2006: 569 (Amo, Yunnan) [near Zhongdian, (28.15483°N, 99.40704°E), Jinsha-Jiang drainage]; Guo et al., 2007 (in part): 58 (Yajiang, Sichuan) [Yalong-Jiang drainage].

Euchiloglanis kishinouyei: Chu et al., 1990: 223 (Judian, Lijiang, Yunnan) [Jinsha-Jiang drainage]; Ding, 1994 (in part): 487– 489 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Chu & Mo, 1999: 162 (Tongtianhe, Qinghai; Judian, Lijiang, Yunnan; Jiangda, Tibet) [Jinsha-Jiang drainage]; Guo et al., 2004a (in part): 261 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Guo et al. 2004b (in part): 1588 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Peng et al., 2004 (in part): 981 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Guo et al., 2005: 348 (Yajiang, Sichuan) [Yalong-Jiang drainage]; Guo et al., 2007 (in part): 58 (Yajiang, Sichuan) [Yalong-Jiang drainage].

Coraglanis kishinouyei: Chu, 1979 (in part): 77 (Yunnan, Tibet, Qinhai) [Jinsha-Jiang drainage]; Wu & Chen, 1979 (in part): 293 (Tongtian-He in Yushu, Qinhai) [upper Jinsha-Jiang drainage].

Holotype. SWFC 200505058, 199.6 mm TL, 179.2 mm SL; Sigongli, 30°01’56.50’’ N, 101°00’55.52’’ E, Yalong- Jiang (a tributary of Jinsha-Jiang), Yajiang Co., Ganzi, Sichuan Prov.; X Li, 10 May 2005.

Paratypes. SWFC 200505059, 200505061-62, 3 ex., 174.5–198.4 mm TL, 155.6–175.2 mm SL; data as for holotype. UF 177382, 2 ex. 123.0–133.0 mm TL, 105.6–117.2 mm SL and SWFC 200108240-41, 2 ex., 137.0– 150.0 mm TL, 121.2–130.0 mm SL; Wujing, 27°41’55.26’’ N, 99°27’39.35’’ E, Jinsha-Jiang, Zhongdian Co., Yunnan Prov.; Q Zhang and YW Zhou, 18 Aug. 2001. SWFC 200004044, 1 ex., 191.0 mm TL, 169.0 mm SL; Benzilan, 28°14’28.40’’ N, 99°18’21.60’’ E, Jinsha-Jiang, Deqin Co., Yunnan Prov.; YW Zhou and XF Pan, 23 April 2000. SWFC 200108210, 1 ex., 147.0 mm TL, 126.0 mm SL; Dongwang, 28°34’20.73’’ N, 99°41’13.57’’ E, Jinsha-Jiang, Zhongdian Co., Yunnan Prov.; XF Pan and F Wu, 18 Aug. 2001. SWFC 200505001-02, 200505006, 200505009, 200505010-11, 200505013, 7 ex., 112.6–142.4 mm TL, 96.7–127.8 mm SL; Xianshui, 30°58’40.32’’ N, 101°07’30.85’’ E, Yalong-Jiang, Daofu Co., Ganzi, Sichuan Prov.; Y Yang, 7 May 2005. SWFC 200505042-43, 2 ex., 139.7–157.5 mm TL, 125.5–141.5 mm SL; Xinduqiao, 30°00’57.55’’ N, 101°32’02.57’’ E, Yalong-Jiang, Kangding Co., Ganzi, Sichuan Prov.; Y Yang, 10 May 2005. SWFC 200505044-47, 200505049-51, 7 ex., 132.1– 158.8 mm TL, 119.2–142.4 mm SL; Wenjiaping, 28°32’05.09’’ N, 101°45’04.32’’ E, Yalong-Jiang, Jiulong Co., Ganzi, Sichuan Prov.; X Li, 10 May 2005. SWFC 200505088-89, 2 ex., 172.7–200.3 mm TL, 152.4–178.2 mm SL; Bamei, 30°24’15.20’’ N, 101°45’26.86’’ E, Yalong-Jiang, Daofu Co., Ganzi, Sichuan Prov.; Y Yang, 9 May 2005.

Diagnosis. Euchiloglanis longibarbatus differs from E. davidi , E. kishinouyei , and E. longus n. sp. by having a pointed maxillary barbel, elongated as a thread, with the tip reaching posteriorly beyond the gill opening ( Fig. 2 C) (vs. the maxillary barbel not elongated as a thread, with the tip only reaching to the gill opening, Fig. 2 A, B, D). Euchiloglanis longibarbatus differs from E. kishinouyei , E. davidi and E. longus n. sp. by having three indentations in the premaxillary tooth band, one in the middle and two on the sides ( Fig. 3 C) (vs. E. kishinouyei without indentations, Fig. 3 B; E. davidi and E. longus n. sp. with a median indentation, Fig. 3 A, D). It differs from E. davidi by having the length of the pectoral fin equal to 71.2–89.9% (vs. 90.5–117.1%) of the distance between the insertions of the pectoral and pelvic fins ( Table 1), and from E. davidi and E. longus n. sp. by having the distance between the insertion of the pelvic fin and the anus equal to 75.5–92.2% (vs. 100.0–125.0 and 108.9–130.0% respectively) of the distance between the insertions of the pectoral and pelvic fins ( Tables 1 and 2 ). Euchiloglanis longibarbatus differs from E. dorsoarcus by having the anal-fin origin closer to the caudal-fin base than to the pelvic-fin origin (vs. the anal-fin origin closer to the pelvic-fin origin than to the caudal-fin base), and 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). Euchiloglanis longibarbatus further differs from E. longus n. sp. by having the depth of the caudal peduncle equal to 26.8–44.5% (vs. 14.1–27.0%) of the caudal-peduncle length.

Description. Morphometric and meristic data are in Table 2 . 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, elongated as a thread with pointed tip ( Fig. 2 C), reaching posteriorly beyond 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 three indentations, one in middle and two laterally. Depth of indentation increases slightly with growth. Lateral edges of premaxillary tooth band extend posteriorly ( Fig. 3 C). 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 opposite 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 pelvicfin origin. Distance from pelvic-fin origin to anal-fin origin shorter than distance from pelvic-fin origin to pectoralfin 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, gray-yellow on dorsal surface with scattered small black spots. Abdomen milk-white. Pectoral and pelvic fins gray-yellow with lighter color around distal edges. Tip of caudal fin gray-black with irregular light yellow patch medially.

Distribution. Known from the Jinsha-Jiang drainage (upper Yangtze River basin, China), including the upper Jinsha-Jiang and the Yalong-Jiang ( Fig. 4 ).

Habitat and ecology. The reaches where the types were collected are steep with dangerous shoals. The river bed is about 20 m width with cobblestones and rock substrate. The current is rapid and water is clear. According to villagers, Euchiloglanis longibarbatus n. sp. preys on other small fishes. They also feed on aquatic insects and small snails. Remains of small fishes were found in the intestines of dissected Euchiloglanis longibarbatus n. sp. specimens. When collecting specimens, we fished them by angleworms and aquatic insects. Adults spawn in apertures of the river bottom in May to June and the eggs are viscous.

Etymology. From the Latin long, meaning long; barbatus, meaning barbel, in reference to the long maxillary barbel. A noun in apposition.

Figures

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 6. Euchiloglanis longibarbatus, SWFC 200505058, holotype, 179.2 mm SL; Sigongli, Yajiang Co., Sichuan Prov., China. Dorsal, lateral and ventral views. Scale bar = 10 mm.

Tables

TABLE 2. Counts and measurements of E. longibarbatus n. sp.

Locality Number specimens Dorsal-fin rays Pectoral-fin rays Pelvic-fin rays	Holotype Sichuan: Yajiang i, 5 i, 12 i, 5	Paratypes Sichuan: Yajiang, Daofu, Kangding Jiulong Yunnan: Deqin, Zhongdian 27 i, 5-6 i, 12–14 i, 5
Anal-fin rays Branched caudal-fin rays in % of standard length Predorsal length	i, 5 7+8 38.8	i, 4–5 7+8 mean range SD 36.3 32.2–41.9 2.31
Dorsal-fin base length Body depth	11.3 15.1	11.0 8.9–15.4 1.63 13.3 10.0–18.1 1.94
Head length Maximum head width Caudal peduncle length Caudal peduncle depth	26.3 25.2 21.0 7.0	24.0 17.7–29.1 2.83 22.3 19.0–26.7 2.01 22.8 19.0–25.4 1.60 7.5 6.2–8.7 0.68
Dorsal-fin insertion to adipose-fin origin Snout to adipose-fin origin	18.7 66.6	18.8 10.0–25.0 4.00 64.8 59.0–69.1 2.80
Dorsal-fin length Pectoral-fin length Pelvic-fin length Anal-fin length	18.8 23.7 17.4 13.5	18.9 16.1–20.3 1.06 24.7 21.3–27.3 1.16 17.9 15.4–20.3 1.03 14.9 12.4–19.1 1.21
Anal-fin base length Caudal-fin length	6.1 16.7	6.9 5.1–9.2 0.97 17.3 11.8–20.0 1.86
Adipose-fin base length in % of head length Snout length Eye diameter Interorbital width in % of Pt-Pl length	25.9 59.9 4.7 30.4	27.9 22.6–34.2 3.08 58.8 47.2–82.6 8.63 6.1 3.8–9.1 1.54 30.6 22.1–45.7 5.98
Pectoral-fin length Pl-A length in % of Pl-A length Pelvic-fin length	76.4 81.3 69.0	83.6 71.2–92.8 5.28 87.6 75.5–104.9 8.27 69.5 60.7–82.0 5.39
in % of length of caudal peduncle Caudal peduncle depth	33.5	33.0 26.8–44.5 4.55