Garra waensis Lothongkham, Arbsuwan & Musikasinthorn, 2014, new species

Garra waensis, new species

(Figs 1–5, Tables 1, 2)

Material examined. Holotype: THNHM-F 0 1511, 90.9 mm SL; the Mang River (a tributary of the Wa River, the Nan River basin, the Chao Phraya River system) at Ban Phuyuen Pathana, Bo Kluea District, Nan Province, Thailand (19°17′43″N, 101°17′42″E), A. Lothongkham, 23 August 2008.

Paratypes: RMUTLN-P 0 0 1, 4 specimens, 54.1–83.4 mm SL, the Mang River at Ko Kuang Village, Bo Kluea District, Nan Province, Thailand (19°18′17″N, 101°13′16″E), A. Lothongkham, 24 August 2008; CAS 233492, 6 specimens (dissected, 1 of 6), 41.5–57.5 mm SL, data as for RMUTLN-P 001; RLIKU 1877, 1 specimen (dissected), 64.2 mm SL, data as for RMUTLN-P 001; RLIKU 1875, 4 specimens, 52.4–64.4 mm SL, the La River (a tributary of the Mang River) at Pha Cup Village, Bo Kluea District, Nan Province, Thailand (19°12′61″N, 101°15′01″E), A. Lothongkham, 11 January 2009; RLIKU 1876, 3 specimens (dissected, 3 of 3), 79.5–82.3 mm SL, data as for RLIKU 1875; CAS 233491, 8 specimens, 47.5–55.4 mm SL, data as for RLIKU 1875; NSMT-P 106508, 2 specimens (dissected, 1 of 2), 63.6–67.0 mm SL, data as for holotype.

Diagnosis. A species of Garra distinguishable from all other congeners by the combination of the following characters: barbels absent; 7 branched dorsal-fin rays; 31–37+2 lateral-line scales; 10–12 circumpeduncular scales; elongated body (body length 73.9–77.3% SL; body depth 16.4–21.1% SL); small and broad head (head length 22.7–26.1% SL; head depth 56.1–64.9% HL, 12.9–16.2% SL; head width 74.0–85.0% HL, 17.1–20.5% SL); a poorly developed proboscis in front of nostrils; the presence of reddish orange spots (white or dull yellowish white in preserved specimens) on body side; a dark mid-lateral stripe running from upper edge of gill opening to caudal peduncle and expanding into a large anteriorly-pointed triangular blotch on caudal peduncle (in preserved condition); and red to pale red color in all fins (in live and fresh condition).

Description. Meristic and morphometric characters are shown in Tables 1 and 2 respectively. Body elongate, slender (body length 73.9–77.3% SL, depth 16.4–21.1% SL, width 15.4–18.9% SL), widest just behind gill cover, deepest at dorsal-fin origin, slightly depressed anteriorly, compressed posteriorly. Predorsal profile of body slightly convex in lateral view. Ventral surface of abdomen flattened. Lateral line complete, running slightly downward on ⅓ of anterior half of body and then along middle of side of body and through caudal peduncle. Chest and belly scaled, scales embedded under skin. Origin of dorsal fin slightly anterior to pelvic-fin insertion. Distal margin of dorsal fin concave. Last unbranched dorsal-fin ray not ossified. First branched dorsal-fin ray longest, tip of adpressed last ray not reaching anal-fin origin. Anterior margins of pectoral and pelvic fins arched. Pectoral and pelvic fins inserted horizontally to somewhat descending posteriorly at ventral margin of body, not reaching pelvic and anal-fin origins, respectively (Figs. 1, 2). Only anterior-most fin ray unbranched in pectoral fin. Pelvic fin inserted at vertical through base of last simple or first branched dorsal-fin rays (Figs. 1, 2). Pelvic fin reaching beyond anus but not reaching anal-fin origin (Fig. 2). Distal margin of anal fin slightly concave. Caudal fin forked.

Head relatively short (length 22.7–26.1% SL), broad (width 17.1–20.5% SL, 74.0–85.0% HL), depressed (depth 12.9–16.2% SL, 56.1–64.9% HL). Interorbital region slightly convex (Fig. 3 A, B). Eye small (orbit diameter 4.0–5.9% SL, 17.4–23.9% HL), placed dorsolaterally in around middle of head. Anterior narial tube with oblique terminal opening, its posterior portion expanded as a semicircular, outward-turned flap bearing numerous minute buds on anterior surface (Figs. 3 A, B, 4A). Posterior naris hole-like, attaching to the anterior nostril (Fig. 4 A). Snout rounded in dorsal and ventral views and somewhat pointed in lateral view with ca. 10–50 variously sized, pointed tubercles scattered mainly around the tip (Fig. 3). Numerous smaller minute tubercles scattered on dorsal, lateral and ventral sides of head (Fig. 3). A poorly developed proboscis in front of nostril (Fig. 3 A, B). Barbels absent (Figs. 3, 5). Mouth strongly inferior, its opening arched anteriorly (Fig. 3 C). Rostral cap welldeveloped, entirely covering upper lip, connected with lower lip around corners of mouth (Fig. 3 C). Ventral margin of rostral cap crenulated, densely papillated with numerous finger-like projections at margin (Fig. 3 C). Upper-lip greatly reduced or vestigial, with many tiny papillae arranged in a longitudinal row on upper jaw (Fig. 3 C). Anteromedial fold of lower lip transverse, densely papillated with numerous minute finger-like projections at posterior margin (Fig. 5). Suctorial disc of lower lip well-developed, wider than long (width 54.2–64.6% HL, length 33.7–42.1% HL) (Fig. 3 C). Anterolateral lobe of lower lip moderately developed, squarish, fully covered by papillae (Fig. 3 C). Front surface of lateroposterior flap of lower lip entirely covered by numerous tiny buds or papillae (Fig. 3 C). Pharyngeal teeth biserial, tooth pattern 3,5–5,3, each tooth pointed at top, recurved mesially (Fig. 4 B). Intestine running straight from esophagus toward the posterior end of abdominal cavity, then curving up in S-shaped loop toward origin, curving back toward posterior end of abdominal cavity 5 times, then running to posterior end of abdominal cavity, connecting to anus (pattern G5b of Kafuku [1997]) (Fig. 4 C).

Morphology of vomero-palatine organ (Fig. 5). Vomero-palatine organ (VPO) relatively simplified, composed of numerous fleshy, multi-directional ridges connected to each other, forming reticulated patterns and occupying mainly the anterior half of mouth roof with some wrinkles and papillae at bottom (complexity of the pattern increases with size of specimens). Anterior portion of VPO partly covered under maxillary valve and rostral cap, extending to posterior half of a fleshy surface of each of right and left preethmoid and the region in between. As a part of the reticulated patterns, a longitudinal row composed of three anteriorly-pointed heart or arrow-like shaped patterns (pockets) present from the anterior portion to center of mouth roof. Anterior portion of anteriormost one covered by maxillary valve. Posteriormost one at center of mouth roof always larger, more distinct than more anterior patterns. Indistinct patterns of shallower fleshy ridges at a portion covered by rostral cap and posterior half of mouth roof, extending to anterior portion of pharynx. Numerous small papillae of various shapes at anterior portion of pharynx. Some of those papillae minutely papillated on their surfaces.

Coloration. When fresh (Fig. 1): Dorsal and lateral sides of body including head dark brown. Ventral side of body and head from rostral cap to caudal peduncle, white. Scales each possessing a reddish-orange spot (pale, dull or dull yellowish white in some scales) at center (occupying about half to entire area of each scale) scattered laterally on body. In larger specimens (Fig. 1), each scale with an orange spot restricted to two rows of scales above and below a lateral-line scale row including lateral-line scale row itself. In some specimens, scales each with an orange spot below and on lateral-line scales possessing golden anterior margins. A large irregular-shaped black blotch at center of lateral sides of posterior portion of caudal peduncle. All fin rays brackish with pale-red to red on branched rays, brighter red on unbranched rays. All fin membranes semi-hyaline pale red.

In alcohol (Fig. 2): Dorsal and lateral side of body including head dark brown. Ventral side of body and head yellowish brown. A dark mid-lateral stripe (its width somewhat narrower than width of scales on flank) running from upper edge of gill opening to caudal peduncle and expanding into a large anteriorly pointed triangular (sometimes irregular) shaped blotch at end of body. Mid-lateral stripe obscure on anterior half of body in some specimens. A dark mid-dorsal stripe running from occiput to anterior portion of caudal peduncle. All fins possessing rays with blackish-brown pigments, membranes pale white. All formerly orange, gold and red areas white or dull yellowish white.

Distribution and habitat. Garra waensis is presently known only from the Wa River (locally called as “Nam Wa”), a tributary of the Upper Nan River in Bo Kluea District, Nan Province, northern Thailand (Fig. 6). The type locality, the Mang River, a tributary of the Wa River at Phuyuen Pathana Village, is a moderate-sized, swift, clear mountain stream (width 6–7 m, depth 0.4–0.6 m) (Fig. 6). The bottom substrate composed of gravel and rock with attached filamentous algae. Other fish species collected at this locality were Poropuntius sp., Scaphiodonichthys acanthopterus, Balitoropsis leonardi, Sectoria atriceps, Schistura menanensis and Glyptothorax laosensis.

Etymology. The name waensis refers to the Wa River which is the only known basin occupied by the species.

FIGURE 6. Collection localities of Garra waensis. Left, map showing the type locality (▲) and localities of paratypes (●). Broken lines indicate national boundaries between Thailand and Laos. Drawn by Amornchai Lothongkham. Right, the type locality, the Mang River, a tributary of the Wa River, the Nan River basin of the Chao Phraya River system at Ban Phuyuen Pathana, Bo Kluea District, Nan Province, northern Thailand (19°17'43"N, 101°17'42"E), looking downstream, 23 August 2008. Photo by Amornchai Lothongkham.