Microphysogobio wulonghensis, Xing, Ying-Chun, Zhao, Ya-Hui, Tang, Wen-Qiao & Zhang, Chun-Guang, 2011

Xing, Ying-Chun, Zhao, Ya-Hui, Tang, Wen-Qiao & Zhang, Chun-Guang, 2011, A new species, Microphysogobio wulonghensis (Teleostei: Cypriniformes: Cyprinidae), from Shandong Province, China, Zootaxa 2901, pp. 59-68 : 60-66

Microphysogobio wulonghensis sp. nov.

( Fig. 2 ; Table 1 )

Holotype. ASIZB 176476, 41.2 mm standard length ( SL), Wulonghe River (36o 43’ N, 120o 44’ E), Laiyang County, Shandong Province, China; 3 May 1929.

Paratypes. ASIZB 43503, 41.6 mm SL; ASIZB 176473-75 (3 specimens), 39.8–46.8 mm SL; ASIZB 176477- 86 (10), 30.8–43.1 mm SL. Other data including locality as for holotype.

Diagnosis. The new species is distinguished from all congeners by the following combination of characteristics: two-thirds of area between pectoral-fin origin and pelvic-fin origin scaleless ( Fig. 2 a); upper lip with one row of well-developed and compressed triangular papillae; two lateral pads on lower lip well-developed, contacting each other behind medial pad ( Fig. 2 b1, 2b2).

The new species is most similar to Microphysogobio amurensis , M. anudarini , M. chinssuensis , M. hsinglungshanensis , M. linghensis , M. rapidus and M. yaluensis in having incompletely scaled regions on the thoracic and abdominal areas. Additionally, the distributions of these eight species are all north of the Yangtze River ( Fig. 3 ). However, the new species differs in having upper lip with well-developed papillae (vs. simple upper lip without papillae in M. linghensis ), upper lip with compressed triangular papillae, lateral pads contacting each other behind medial pad (vs. upper lip with umbonate papillae, lateral pads separated each other behind medial pad in M. amurensis , M. chinssuensis , M. hsinglungshanensis , M. rapidus and M. yaluensis ), two-thirds of area between pectoralfin origin and pelvic-fin origin scaleless (vs. scaleless region restricted to area before pelvic-fin base in M. anudarini ).

Description. General body features are shown in Fig. 2 . Morphometric and metristic characteristics are listed in Table 1 . Body small, slim and elongated. Thoracic and abdominal regions flat, caudal region compressed. Dorsal profile rising gently from snout tip to dorsal-fin origin, then almost horizontal, or sloping slightly to end of caudal peduncle. Ventral profile horizontal to anal-fin base, then rising gently to caudal fin. Caudal peduncle short and moderately compressed. Greatest body depth exactly at dorsal-fin origin; least depth of caudal peduncle closer to caudal-fin base than to dorsal-fin base. Anus and urogenital opening at one third of area from pelvic-fin origin to anal-fin origin. Air bladder smaller than eye diameter, with slim vessel connecting to intestine, divided into two chambers, anterior chamber oblate, enclosed by thick fibrous capsule; posterior chamber much smaller than anterior one.

continued.

Microphysogobio rapidus Microphysogobio yaluensis Dorsal fin iii, 7 iii, 7

Anal fin ii, 6 ii, 6

Pectoral fin i, 12 – 13 i, 9 – 13

Pelvic fin i, 7 i,7

Total vertebrae 38 – 41 33 – 41

Gill rakers 22 – 25 10 – 26

Lateral-line scales 36 – 38 34 – 39

Scales above lateral-line 4 4

Scales below lateral-line 2 2

Pre-dorsal scales 10 10

Circumpeduncular scales 12 12

Max Min Mean SD Max Min Mean SD Standard length 59.5 54.9 57.2 2.1 60.6 30.7 43.7 6.6 In % of standard length

Body depth 19.7 17.1 18.3 1.4 22.2 15.6 19.0 1.5 Pre-dorsal length 46.6 45.8 46.2 0.3 49.4 42.9 45.9 1.5 Head edge to dorsal 23.6 22.3 23.2 0.6 28.4 21.9 24.9 1.8 Dorsal-fin base length 15.6 13.7 14.7 0.8 22.7 12.0 15.3 1.7 Dorsal-fin length 23.7 21.8 22.6 0.8 28.4 19.5 25.4 1.5 Pre-anal length 77.1 73.9 75.1 1.4 84.9 74.1 78.2 2.2 Anal-fin base length 10.9 8.5 9.8 1.0 13.7 6.7 9.8 1.8 Anal-fin length 15.7 14.1 15.0 0.7 19.6 12.5 15.9 1.4 Pre-pectoral length 26.0 24.5 25.4 0.7 27.9 16.8 24.8 1.7 Pectoral-fin base length 6.9 5.5 6.2 0.7 7.9 4.2 5.6 0.8 Pectoral-fin length 20.7 19.5 19.9 0.6 27.5 18.8 23.4 2.1 Pre-pelvic length 53.4 51.7 52.5 0.9 75.4 19.7 51.0 5.6 Pelvic-fin base length 5.7 4.8 5.4 0.4 6.8 3.7 5.2 0.7 Pelvic-fin length 16.1 14.1 15.2 0.8 21.1 13.6 17.7 1.6 Caudal-peduncle length 16.6 12.8 15.4 1.8 19.7 9.2 14.3 2.5 Caudal-peduncle depth 8.0 7.6 7.9 0.2 10.9 7.9 9.1 0.6 Head length 24.0 22.7 23.1 0.6 24.4 20.0 22.5 1.2 In % of head length

Head depth 768.5 60.8 65.1 3.2 73.3 56.6 63.6 3.9 Head width 766.3 16.6 51.8 24.0 74.9 55.4 66.4 3.8 Snout length 446.0 40.1 43.7 2.6 46.0 29.1 36.5 3.4 Eye diameter 333.4 31.8 32.9 0.7 39.5 24.7 30.7 2.9 Interorbital width 320.3 17.9 18.7 1.1 36.0 18.1 26.8 3.1 Mouth width 339.9 19.6 28.3 8.7 40.9 23.3 30.8 4.2 Rictal barbel length 217.0 11.2 13.4 2.6 26.4 12.0 16.6 3.1 Head triangular from side view. Snout short, rounded, smaller than eye diameter, depressed in front of nostrils. Anterior nostril tubular, short, next to posterior nostril. Mouth inferior, curved; corners opposite to posterior nostrils. Upper lip thick, covering upper jaw; upper jaw invisible when mouth closed; upper lip with one row of welldeveloped and compressed triangular papillae, two or more rows of papillae on corner of mouth. Lower lip divided into three pads, middle one heart-shaped; fleshy protuberances without vertical gap in the center; two lateral pads well-developed and connected to upper lip at corners of mouth, with many papillae, contacting each other behind medial pad. Pair of short rictal barbels, shorter than half of eye diameter. Eyes large and rounded. Interorbital profile slightly concave. Gill openings large, extending downward beyond pectoral-fin base. Gill rakers well-developed. Pharyngeal teeth in one row, 5-5.

Dorsal-fin origin anterior to pelvic-fin origin, nearer to snout tip than to caudal-fin base; distance between snout tip and dorsal-fin origin nearly equal to distance from posterior end of dorsal-fin base to caudal-fin origin. Dorsal fin short, end of dorsal-fin base opposite to posterior end of pelvic-fin base; last unbranched ray soft. Pectoral fin short, ending two scales away from pelvic-fin origin when adpressed; insertion at vertical through posterior margin of operculum, end extending opposite to dorsal-fin origin. Pelvic-fin insertion midway between pectoral-fin origin and anal-fin base, opposite to second or third branched ray of dorsal fin. Anal fin short, insertion nearly midway between pelvic-fin origin and caudal-fin base. Caudal fin bifurcate, upper lobe slightly shorter than lower one.

Lateral line complete, almost straight. Body covered by moderately sized cycloid scales. Lateral-line scales 31(1 specimen), 32 (4), 33 (2), 34 (1), 35 (3), 36 (3) or 37 (1). Scales above lateral line 4, below lateral line 2 (12) or 3 (3). Pre-dorsal scales 10, regularly arranged. Circumpeduncular scales 8 (1) or 10 (14). Two-thirds of area between pectoral-fin origin and pelvic-fin origin scaleless.

Coloration in alcohol. The specimens were fixed and preserved in formalin in 1929, and transferred to alcohol in 2005. Body brownish, back darker and belly lighter. 8-9 large dark brown spots along mid-side from gill opening to caudal-fin base. Each lateral-line scale has a dark spot. All fins light grayish.

Distribution. From the collection record, the new species is only found in the Wulonghe River, a costal river in the Shandong Peninsula ( Fig. 3 ). The locality is near Laiyang County, Shandong Province, China.

Etymology. The name, wulonghensis , is derived from the name of the collection locality, Wulonghe River (“he” means river in Chinese). The names of most species in this genus are based on the collection locality.

Figures

FIGURE 2. Lateral and ventral views of Microphysogobio wulonghensis sp. nov. Holotype, ASIZB 176476, 41.2 mm SL: a, lateral and ventral views; b 1, photograph of upper and lower lips; b 2, illustration of upper and lower lips.

FIGURE 3. Distribution of Microphysogobio wulonghensis sp. nov. and similar species. Hollow cross, M. hsinglungshanensis; solid square M. anudarini; solid circle, M. chinssuensis; solid star, M. wulonghensis sp. nov.; solid triangle, M. linghensis; hollow square, M. rapidus; hollow circle, M. yaluensis; asterisk M. amurensis.

Tables

TABLE 1. Meristics and morphometrics of Microphysogobio wulonghensis sp. nov. and other species in the “ incompletely scaled ” group.

Dorsal fin	Microphysogobio wulonghensis sp.nov. (n=15) iii, 7	Microphysogobio linghensis (n=6) iii, 7
Anal fin Pectoral fin Pelvic fin Total vertebrae	ii, 6 i, 9 – 11 i, 7 35 – 38	ii, 6 i, 9 – 12 i, 7 35 – 36
Gill rakers Lateral-line scales Scales above lateral-line Scales below lateral-line Pre-dorsal scales Circumpeduncular scales	16 – 18 31 – 37 3 – 4 2 – 3 10 8 – 10	9 – 13 34 – 37 4 2 9 – 10 12