Glyptothorax himalaicus, Vijayakrishnan & Shinde, 2025

Glyptothorax himalaicus , new species

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( Fig. 8 View FIGURE 8 & 9 View FIGURE 9 )

Type material. Holotype: ZSI/NRC F-10671 , 92.2 mm SL; India: Uttarakhand: Ganges River at Haridwar .

Diagnosis. Glyptothorax himalaicus can be distinguished from all Gangetic congeners except G. pectinopterus , G. brevipinnis , G. conirostris , G. bhurainu and G. dakpathari in the presence (vs. absence) of plicate ventral surface on pectoral-fin spine and first pelvic-fin ray ( Fig. 3c & d View FIGURE 3 ). It can be readily distinguished from all of the abovementioned species in having the dorso-lateral surface of body covered with irregular blotches (vs. plain body). It further differs from G. brevipinnis and G. pectinopterus in possessing serrated (vs. smooth) posterior margin of dorsal-fin spine and longer thoracic adhesive apparatus reaching (vs. not reaching) posterior limit of pectoral-fin base; from G. dakpathari in having thoracic adhesive apparatus open caudally (vs. completely encinctured by striae) ( Fig. 4b View FIGURE 4 ), and longer anterior nuchal plate element with rounded anterior margin and pale spots spread throughout (vs. shorter anterior nuchal plate element with pointed anterior margin and pale spots only at lateral tips) ( Fig. 5b View FIGURE 5 ); and from G. conirostris in having elliptical- (vs. ovoid-) shaped thoracic adhesive apparatus and in the absence (vs. presence) of anteromedial striae on the thoracic adhesive apparatus.

Glyptothorax himalaicus further differs from G. telchitta and G. botius in having longer pectoral-fin spine (18.3% SL vs. 12.3–17.0) and deeper caudal peduncle (7.9% SL vs. 3.1–5.9); from G. cavia in having elliptical- (vs. rhomboid-) shaped thoracic adhesive apparatus, absence (vs. presence) of anteromedial striae on the thoracic adhesive apparatus, and shorter head (23.1% SL vs. 29.5); from G. indicus in having unculiferous ridges of thoracic adhesive apparatus not extending (vs. extending) anteriorly onto gular region, and shorter adipose-fin base (11.2% SL vs. 13.6–15.3); from G. garhwali in the absence (vs. presence) of anteromedial striae on thoracic adhesive apparatus and serrated (vs. smooth) posterior margin of dorsal-fin spine; and from G. gracilis in having more slender head (head depth 10.6% SL vs. 11.9–13.9) and larger eye (14.5% HL vs. 9.4–10.8).

Description. Morphometric data in Table 2 View TABLE 2 . Head depressed; body subcylindrical. Dorsal profile rising evenly from tip of snout to origin of dorsal fin, then sloping gently ventral from origin of dorsal fin to end of caudal peduncle. Ventral profile straight till anal-fin base, sloping gently from anal-fin base to end of caudal peduncle. Anus and urogenital openings located almost vertical through middle of adpressed pelvic fin. Skin tuberculate. Lateral line complete and midlateral.

Head depressed and narrow, triangular when viewed laterally. Snout prominent. Anterior and posterior nares large and separated only by base of nasal barbel. Gill opening broad, extending from immediately ventral to post-temporal to isthmus. Bony elements of dorsal surface of head covered with thick, tuberculate skin. Eyes small and round, located on dorsal surface of head. Barbels in four pairs. Maxillary barbel long and slender, extending beyond pectoral-fin base. Nasal barbel slender, extending beyond anterior orbital margin. Inner mandibular barbel extending to pectoral-fin base and outer mandibular barbel extending to middle of pectoral-fin base. Mouth inferior, lips papillate, premaxillary tooth band partially almost wholly exposed when mouth is closed. Oral teeth small and villiform. Premaxillary teeth in a single broad semi-lunate band. Dentary teeth in two narrow crescent shaped bands separated at midline.

Thoracic adhesive apparatus consisting of striae in elliptical field ( Figure 4b View FIGURE 4 ) extending from isthmus to posterior limit of pectoral-fin base; anterolateral edges of adhesive apparatus gently convex. Striae uninterrupted, anteromedial striae absent. Medial pit present and posteromedial, extending for about half length of thoracic adhesive apparatus. Dorsal fin located above anterior third of body, with I,6* (1) rays; fin margin gently concave; spine short and gently curved, anterior margin smooth, posterior with 6 serrations. Adipose fin with anterior margin and posterior margins straight. Caudal fin strongly forked, with i,7,8,i* (1) principal rays. Procurrent rays symmetrical and extending slightly anterior to fin base. Anal-fin base ventral to adipose-fin origin. Anal fin with straight anterior margin and straight or slightly concave posterior margin; with ii,10* (1) rays. Pelvic-fin origin immediately posterior to vertical through posterior end of dorsal-fin base. Pelvic fin with slightly convex margin and i,6* (1) rays; tip of adpressed fin almost reaching anal-fin origin. Pectoral fin with I,9* (1); pectoral spine broad and covered with thick skin. Anterior spine margin smooth, posterior margin with 13 serrations. Ventral surface of pectoral-fin spine and first pelvic-fin ray with plicae ( Figure 3c & d View FIGURE 3 ).

Colouration. In 70% alcohol ( Fig 8 View FIGURE 8 ): dorsal and lateral surfaces of head grey, with irregular dark blotches, fading to yellowish-cream on ventral surfaces. Posterior half of supraoccipital process and both central portion and lateral tips of nuchal plate elements yellow. A thin, pale mid-dorsal stripe extending from base of last dorsal- fin ray to origin of adipose fin. Dorsal, pectoral, pelvic and anal fins yellow at base, black on anterior margins and rays, and hyaline distally. Adipose fin yellow with hyaline distal margin. Caudal fin with dark black patch at its base, rays yellow with irregular black spots, hyaline distally. Barbels grey dorsally and cream ventrally. Colouration in life similar, with darker body and fins ( Fig 9 View FIGURE 9 ).

Etymology. The specific name comes from the Latin ‘himalaicus’ meaning of, or pertaining to the Himalayas, in reference to the location of the type locality in Haridwar, at the foothills of the Garhwal Himalayas in Uttarakhand State, India.

Habitat. Glyptothorax himalaicus was collected from a shallow, fast-flowing stream with a predominantly sandy bottom with cobblestone and pebbles as substrates ( Fig. 6 View FIGURE 6 ). Co-occurring fishes include Glyptothorax bhurainu, Garra sp., Botia almorhae , Labeo sp. , and Tariqilabeo latius .

Distribution. Glyptothorax himalaicus is currently known only from the upper reaches of the Ganges basin in Haridwar district, Uttarakhand, northern India ( Fig. 7 View FIGURE 7 ). The Ganges at the type locality is formed by the confluence of the Alaknanda and Bhagirathi Rivers, approximately 100 kms upstream.