Glyptothorax zeiladensis, Shangningam & Kosygin & Gurumayum, 2024

Glyptothorax zeiladensis sp. nov. ( Figures 1 View Figure 1 )

Material examined: Holotype: 81.0 mm SL, India, Manipur, Tamenglong District, Maruitistream, Zeilad Wildlife Sanctuary near Tongtao village (Barak-Surma-Meghna River drainage), 24°54 ʹ 20.9῞N, 93°22 ʹ 41.16῞E, 7-10-2018, coll. L Kosygin (ZSI FF 8929) . Paratypes: 8 specimens, 63.0–84.0 mm SL, same data as holotype . Two paratypes, 63–71 mm SL dissected for osteology (ZSI FF 8930).

Diagnosis: Glyptothorax zeiladensis sp. nov. is distinguished from its congeners in the Indian subcontinent by the combination of the following characteristics: densely tuberculate skin on the body; an elliptical thoracic adhesive apparatus, almost enclosed posteriorly with skin ridges present over the entire apparatus including the depressed region, not extending to the gular region; anterior nuchal plate saddle-like with W-shaped extensions; nasal barbel short, its length 15–21% HL, not reaching the anterior margin of the eye; body with two longitudinal pale-cream stripes, one each along mid-dorsal line and lateral line, ventral surface of the pectoral-fin spine with reticulated skin ridges Glyptothorax zeiladensis , a new sisorid catfish species (Teleostei: Sisoridae ) from Manipur, India and absence of plicae on the ventral surfaces of the first pelvic-fin ray.

Description: Morphometric data as in Table 1. Body elongated, Dorsal profile steeply rising from the tip of snout to dorsal-fin origin, then gently sloping ventrally from dorsal-fin origin to end of caudal peduncle. Ventral profile flat till pelvic-fin origin, then sloping dorsally towards caudal peduncle. Body, head and adipose fin covered with dense elongated tubercles. The lateral line is complete, running mid-lateral. Vertebrae 18+19=37 or 19+19=38.Head broad and depressed.The snout is slightly convex when viewed dorsally and rounded ventrally. Eyes large, ovoid, horizontal axis slightly longer than vertical axis, located dorsally midway of head length. Anterior and posterior nares are large and separated only by nasal barbel base. Gill openings are broad extending ventral from post temporal to isthmus. Gill on the first branchial arch with 2+7 or 2+8 or 3+7 rakers. Occipital process not in contact with anterior nuchal plate element. Anterior nuchal plate saddle-like with W-shaped extensions when viewed dorsally. Tip of neural spine visible between dorsal and adipose fins.

Mouth inferior with lips papillated, upper jaw longer than lower, premaxillary tooth band entirely exposed when the mouth is closed. Oral teeth are small and villiform. Teeth on upper jaw arranged on crescentic band in four rows with gap in between and in two rows in lower jaw interrupted at midline.

Barbels in four pairs. Maxillary barbel thick, continuing from upper lip, reaching pectoral-fin origin. The nasal barbel is short, originating from the internarial septum, extending to midway between its base and anterior orbital margin. Outer mandibular barbel longer than inner, not reaching pectoral-fin origin. Inner mandibular barbell short, originating anterolaterally to outer mandibular barbel.

Thoracic adhesive apparatus is elliptical, longer than broad, extending from the isthmus to the posterior end of the pectoral-fin base with poorly developed median depression, almost enclosed posteriorly by dermal ridges and skin ridges present over the entire apparatus, including depressed region ( Figure 2 View Figure 2 ). Anus and a urogenital opening located at vertical through posterior end pelvic-fin.

Dorsal fin with i, 6 (8) rays; fin margin convex, located halfway between snout tip and adiposefin origin. Dorsal-fin spine is strong, serrated with 5(3) or 7(2) or 8(3) serrae, longer than the depth of the body. Adipose fin short, anterior margin straight, posterior margin almost straight. Pectoral fin with i, 10(8) rays; posterior fin margin slightly pointed tip. The pectoral spine is broad, covered with thick skin, its posterior margin with 11(3) or 12(2) or 13(3) serrae. Ventral surface of pectoral-fin spine with reticulated skin ridges. Pelvic fin with i, 5(8) rays, its posterior margin slightly convex, surpasses the vent, tip not reaching anal-fin origin. Anal fin with iii, 8(2) or iv, 9(6) rays, almost straight posterior margin. Caudal fin with 7+8 branched rays, strongly forked, with lower lobe slightly longer than upper lobe.

Colouration: In 70% alcohol: dorsal and lateral surface of head and body greyish brown, ventral surface up to the origin of anal fin yellowish. Two yellowish thin stripes on the body: one mid-dorsal, extending behind the occipital process and another mid-lateral, originating at the level of origin of the pectoral fin, both stripes reaching the base of the caudal fin. Dorsal, pectoral pelvic and anal fins with dark-brown bases with yellowish margins. The adipose fin is brown, its base and distal margin yellowish. Caudal fin brown. Nasal, maxillary barbels brown. Mandibular barbels are yellowish.

Sexual dimorphism: No sexual dimorphism observed.

Distribution: The species is presently known only from the type locality, Maruiti stream, Zeilad Wildlife Sanctuary near Tongtao village, Tamenglong District, Manipur (Barak-Surma-Meghna River drainage), India.

Etymology: The species is named after its type locality, the Zeilad Wildlife Sanctuary.