Altigena lippa ( Fowler 1936 )

Ciccotto, Patrick J., Lin, Feng & Chen, Xiao-Yong, 2021, Taxonomic revisions of Altigena laticeps and A. lippa (Cyprinidae: Labeoninae) from the Mekong River Basin, Zootaxa 4941 (2), pp. 271-280 : 275

Altigena lippa ( Fowler 1936)

Figure 4

Labeo lippus Fowler 1936

Bangana lippus — Kottelat 1998

Sinilabeo longirostris— Nguyen, in Nguyen & Ngo 2001

Sinilabeo brevirostris— Nguyen, in Nguyen & Ngo 2001

Bangana lippa —Zheng & Chen 2006

Diagnosis. A member of Altigena based on characters listed by Kottelat (2017). Altigena lippa can be distinguished from all species in the genus by the following combination of characters: 9–12 predorsal scales; 34–39 lateral-line scales; and 16 circumpeduncular scales.

Description. Morphometrics of type and non-type material presented in Table 1. Mouth inferior, strongly arched. Rostral cap thick, pendulous; crenulated medially, smooth laterally in smaller specimens, uniformly smooth in larger specimens, separated from upper lip by deep groove, covering all but edge of upper lip. Upper lip entirely enclosing upper jaw, edge smooth, continuous with labial fold at corners of mouth. Labial fold thin and papillose, separate from lower jaw by deep grove, margined posteriorly by plical groove. Pair of gular grooves present, connected with plical groove. Maxillary barbels, if present small, absent from larger specimens. Three rows of tubercles on tip of snout, sublachrymal grooves on sides of rostral cap partially divide anteriormost row from posterior rows. Shallow ethmoidal furrow present, separating 3 rows of tubercles on snout from row or patch of small tubercles between nares.

Dorsal profile slightly arched, deepest at dorsal-fin insertion. Ventral profile flat to slightly concave. Head short, longer than wide; snout conical, rounded or triangular when viewed from dorsal side; eyes dorsolateral. Dorsal-fin origin anterior of pelvic-fin origin. Pectoral fins positioned ventrally, reaching approximately 2/3 from origin to pelvic-fin origin. Pelvic fins reaching ¾ to anal fin. Anal fin just reaching insertion of caudal-fin when adpressed. Dorsal and anal fins concave to falcate; pectoral and pelvic fins triangular. Caudal fin forked. Axillary pelvic lobes well-developed.

Dorsal fin with 3 simple and 9½–10½ branched rays; anal fin with 3 simple and 5½ branched rays; pelvic fin with 1 simple 8–9 branched rays; pectoral fin with 1 simple and 13–15 branched rays; caudal fin with 10+9 principal rays, 9+8 branched. Body entirely scaled except for predorsal midline; scales on chest smaller and more embedded than remainder of body. Lateral-line scales and pored scales on caudal fin 34–39; predorsal scales 9–12; scale rows between dorsal-fin insertion and lateral line 5–5½; scale rows between anal-fin insertion and lateral line 4½–5½; scale rows between pelvic-fin origin and lateral line 3½–5½; 16 circumpeduncular scales.

In preservative ( Fig. 4 ), smaller specimens (less than 180 mm SL) brown to cream, generally lighter on venter; dark brown vertically elongate blotch present at base of caudal peduncle. Fins clear except for tiny melanophores on interradial membranes of dorsal and caudal fin. Larger specimens (greater than 180 mm SL) darker brown, without brown blotch at base of caudal peduncle.

Distribution. Altigena lippa is distributed in the Lower Mekong River basin in Lao PDR, Myanmar, and Thailand ( Fig. 3 ), as well as Vietnam ( Nguyen & Ngo 2001). Its currently known distribution extends as far south as the Nam Ngiep basin, the first major tributary of the Mekong upstream of the Nam Kading River, in Lao PDR ( Kottelat 2015).

Material Examined. Lao PDR: UMMZ 240701 , 7 , 131.4 –178.0 mm SL, Louang Nam Tha Province, Louang Nam Tha morning market, 20.98333N, 101.1E ; UMMZ 240723 , 1, 116.9 mm SL, Oudom Xai Province, Muang Xai market, 20.7N, 101.9667E ; UMMZ 240977 , 1, 101.4 mm SL, Phongsali Province, Nam Long, just upstream from confluence with Nam Ou , 21.76667N, 102.2E ; UMMZ 241536 , 1, 267.5 mm SL, Luang Namtha Province, Luang Namtha morning market, 20.96667N, 101.4E ; UMMZ 241767 , 1, 125.1 mm SL, Pak Beng market, from mouth of Nam Beng. Myanmar : ANSP 64159 , 1 (holotype), 225.2 mm SL, Shan States, Meng Pek, Mong Lin , 20.724306N , 100/14693E. Thailand: CAS 92518, 2 , 102.4 – 120.8 mm SL, Huay Mae, about 4–5km north of Chieng Kang on road to Chieng San , 20.298492N, 100.388585E .

Figures

FIGURE 3. Distributions of georeferenced specimens examined of Altigena laticeps and A. lippa. Map by D. Boyd (FLMNH).

FIGURE 4. CAS 92518, Altigena lippa, 120.8 mm SL. Photograph by Z. Randall (FLMNH).