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Electronic Journal of Ichthyology November, 2007 2: 35-45 THE IDENTITY OF TACHYSURUS SINENSIS LA CEPÈDE, 1803, WITH THE DES- IGNATION OF A NEOTYPE (TELEOSTEI: BAGRIDAE) AND NOTES ON THE IDENTITY OF T. FULVIDRACO (RICHARDSON, 1845) Heok Hee Ng1, Maurice Kottelat2 1 Raffles Museum of Biodiversity Research, Department of Biological Sciences, 6 Science Drive 2 #03-01, National University of Singapore, Singapore 117546. Email: [email protected] 2Case Postale 57, Cornol, CH-2952, Switzerland. Email: [email protected] Submitted: September, 3 2007 Accepted October, 21 2007 Abstract: The identity of Tachysurus sinensis, a species previously thought to be an East Asian ariid, but now believed to be a bagrid, is fixed with the designation of a neotype. The neotype designation is necessary because of previous misapplications of the name and the ambiguity surrounding the identity of the species, the description of which was based on a Chinese painting. The neotype designation results in Tachysurus being a subjective senior synonym of Pseudobagrus. The evidence that what is currently recognized as T. fulvidraco consists of at least two species is briefly discussed, with the name T. sinensis restricted to the species found in northern China and T. fulvidraco for the species found in southern China. Keywords: Catfish - Ostariophysi - Siluriformes - East Asia Introduction sinensis to fix the identity of the species and The generic name Tachysurus La Cepède, the genus, as well as redescribe the species. 1803 (type species Tachysurus sinensis La The neotype for T. sinensis is a specimen Cepède, 1803, by monotypy), has been used from northern China previously identified as intermittently over the last 100 years for Pseudobagrus fulvidraco (Richardson, ariid catfishes (e.g. Eigenmann & Eigen- 1845), a species described from southern mann, 1890; Fowler, 1932; Jayaram & China. We present and discuss evidence Dhanze, 1978); in fact it was more com- herein that the northern and southern Chi- monly used than Arius until 1981 (Wheeler nese populations of material previously & Baddokwaya, 1981). In many of these identified as P. fulvidraco represent distinct works, Tachysurus is considered a senior species. synonym of Arius Valenciennes in Cuvier & Valenciennes, 1840. The identity of Tachy- Materials and Methods surus sinensis has not been established with Measurements were made point to point certainty, but Wheeler & Baddokwaya with dial calipers and data recorded to tenths (1981) discuss evidence that it is not an of a millimeter. Counts and measurements ariid. Since then, Tachysurus sinensis has were made on the left side of specimens remained incerta sedis (Ferraris, 2007), al- whenever possible. Subunits of the head are though it has been provisionally assigned to presented as proportions of head length the Bagridae in recent literature (Kailola, (HL). Head length and measurements of 2004). body parts are given as proportions of stan- We provide evidence here that Tachysu- dard length (SL). Measurements follow rus sinensis is a species of Pseudobagrus those of Ng & Dodson (1999), except for Bleeker, 1859, designate a neotype for T. vertebral counts, where counts are given as 35 Ng HH. Kottelat M., 2007 Identity of Tachysurus sinensis abdominal (open hemal arches) + caudal tutional abbreviations follow Eschmeyer (closed hemal arches). Asterisks after meris- (1998). tic counts indicate values for neotype. Insti- Figure 1. Tachysurus sinensis, neotype, USNM 336888, 114.4 mm SL. Dorsal, lateral and ventral views. 36 Ng HH. Kottelat M., 2007 Identity of Tachysurus sinensis Tachysurus sinensis La Cepède, 1803: 305 (type Diagnosis. Tachysurus sinensis is distin- locality: China) guished from all congeners (except T. (?) Silurus calvarius Basilewsky, 1855: 241, Pl. 9 Figure 1 (type locality: running and stagnant wa- fulvidraco) in having a combination of brown ters of Gulf of Tschili [=Bohai Sea], China) elongate rectangular blotches on a light brown (?) Pseudobagrus wittenburgii Popta, 1911: 335 body, a moderately forked caudal fin, serra- (type locality: Amur River at Blagoveshchensk tions on the anterior and posterior edges of the [=Blagovescensk], Russia) pectoral spines. It differs from T. fulvidraco in Neotype. USNM 336888, 114.4 mm SL; having a slenderer caudal peduncle (7.3–9.6% China: Beijing, Huairou County, Huairou SL vs. 9.5–10.9), shorter snout (29.8–32.2% Reservoir, approximately 2 km NE of ob- HL vs. 32.2–37.5) and steeper predorsal pro- servatory, 40°19'00"N 116°37'31"E; L. R. file that is slightly convex (vs. gentler-sloping Parenti & C-G Zhang, 24 March 1995. profile that is slightly concave). Other material examined. USNM Description. Morphometric data as in Ta- 390434 (8), 35.8–185.0 mm SL; data as for ble 1. Head moderately compressed; dorsal neotype. profile slightly convex and ventral. Table 1. Morphometric data for Tachysurus sinensis (n=9). Neotype Range Mean ±SD Standard length (mm) 114.4 35.8–185.0 %SL Predorsal length 40.4 39.3–41.0 40.2±0.76 Preanal length 64.2 63.4–67.7 64.7±1.75 Prepelvic length 52.2 51.3–54.1 52.9±1.16 Prepectoral length 24.0 24.0–27.4 25.6±1.46 Length of dorsal-fin base 12.6 11.3–15.0 12.8±1.36 Dorsal-spine length 18.9 16.9–22.4 20.1±2.22 Anal-fin length 23.3 20.5–23.8 22.7±1.29 Pelvic-fin length 14.8 13.8–17.3 15.6±1.41 Pectoral-fin length 22.4 20.9–23.8 22.1±1.28 Pectoral-spine length 18.9 18.5–21.8 19.9±1.61 Caudal-fin length 24.3 13.6–24.8 21.8±4.68 Length of adipose-fin base 19.8 15.4–19.9 17.8±2.04 Dorsal to adipose distance 15.9 12.8–17.2 15.4±1.63 Post-adipose distance 16.6 16.4–18.3 17.2±0.77 Caudal peduncle length 15.3 14.4–16.2 15.5±0.72 Caudal peduncle depth 8.8 7.3–9.6 8.6±0.69 Body depth at anus 19.7 17.4–20.4 19.0±1.30 Head length 29.9 29.5–30.9 30.4±0.64 Head width 21.1 20.8–24.4 22.4±1.29 Head depth 19.2 18.1–20.2 19.5±0.88 %HL Snout length 30.1 29.8–32.2 30.9±0.73 Interorbital distance 39.2 36.8–41.6 38.4±2.52 Eye diameter 17.3 16.1–19.5 17.8±1.27 Nasal barbel length 45.9 33.2–57.5 46.9±9.63 Maxillary barbel length 90.4 90.4–99.7 94.9±4.27 Inner mandibular barbel length 46.2 39.6–56.5 46.6±6.54 Outer mandibular barbel length 64.0 61.9–83.8 72.3±9.15 37 Ng HH. Kottelat M., 2007 Identity of Tachysurus sinensis profile almost straight; snout broadly Dorsal fin with spinelet, spine, and 7 (9) rounded when viewed dorsally. Bony ele- rays. Origin of dorsal fin anterior to mid-body, ments of dorsal surface of head covered about two-fifths of body. Dorsal fin margin with thin skin. Supraoccipital process slightly convex. Dorsal fin spine short, moderately thick, with parallel sides and straight and slender, posterior edge without notched tip; in contact with anterior nuchal serrations. Nuchal plates in form of triangle plate. Eye ovoid, horizontal axis longest, with slightly rounded sides, with pointed tip located entirely in dorsal half of head. Gill anteriorly. openings wide, extending from posttempo- Pectoral fin with stout spine, sharply ral to isthmus. pointed at tip, and 6,i (9) rays. Anterior spine Mouth subterminal. Oral teeth small and margin with 10–31 small serrations; posterior viliform, in irregular rows on all tooth- spine margin with 6–18 large serrations along bearing surfaces. Premaxillary tooth band entire length. Pectoral fin margin straight an- rounded, of equal width throughout. Den- teriorly, convex posteriorly. Cleithral process tary tooth band much narrower than pre- narrow, extending for three quarters or more maxillary tooth band at symphysis, taper- of pectoral-spine length. ing laterally. Vomerine tooth band un- Pelvic fin origin at vertical through mid- paired, continuous across midline; point of distance between base of posterior- smoothly arched along anterior margin, most dorsal-fin ray and origin of adipose-fin tapering laterally to point extending poste- base, with i,5 (9) rays and slightly convex riorly past level of premaxillary band; band margin; tip of adpressed fin not reaching anal width narrower than premaxillary band at fin origin. Anus and urogenital openings lo- midline, widening laterally and then taper- cated at vertical through middle of adpressed ing to a sharp point posterolaterally. pelvic fin. Males with a conical genital papilla Barbels in four pairs. Nasal barbel slen- just reaching base of first anal-fin ray. der, extending beyond vertical through Adipose fin with convex margin for entire posterior orbital margin. Maxillary barbel length, with deeply-incised posterior portion broad, extending to beyond base of last and origin approximately at vertical through pectoral fin-ray. Inner mandibular-barbel base of first anal-fin ray; fin-base short, span- origin close to midline; barbel thicker and ning slightly less than one-third of postdorsal longer than nasal barbel and extending for distance. Anal fin base at vertical through ori- three-quarters distance between its base gin of adipose fin, with v,14 (1), vi,14 (1), and base of pectoral spine. Outer mandibu- v,15 (2), iv,16* (4) or v,16 (1) rays and con- lar barbel originating posterolateral of in- vex posterior margin. ner mandibular barbel, extending to middle Caudal peduncle moderately deep.