Devario deruptotalea, Ramananda, Yumnam & Vishwanath, Waikhom, 2014

Ramananda, Yumnam & Vishwanath, Waikhom, 2014, Devario deruptotalea, a new species of cyprinid fish from Manipur, India (Teleostei: Cyprinidae), Zootaxa 3827 (1) : -

Devario deruptotalea , new species

( Fig. 1 )

Holotype. MUMF 16001, 63.4 mm SL: India: Manipur state, Chandel District, Dutah Stream, a tributary of Yu River (Chindwin drainage); 24°15′03ʺ N 94°14′ 59ʺ E, 283 m asl, Y. Ramananda & party, 19 Mar 2013.

Paratypes. ZSIFF 5153, 2, 58.4−60.9 mm SL; MUMF 16002, 60.8 mm SL; MUMF 16005 −16014, 11, 52.5–62.4 mm SL; same data as holotype. Two paratypes ( MUMF 16013 & 16014, 56.7–59.2 mm SL) were dissected for osteology.

Diagnosis. A medium-sized Devario species reaching 63.4 mm SL, distinguished from its congeners in the Chindwin drainage in having the following combination of characters: complete lateral line with 32–34 pored scales; unique colour pattern consisting of 4–6 dark brown irregularly shaped and arranged bars, each of which is partly confluent with adjacent bar at different levels on anterior one-third of side of body, followed by three distinct dark brown stripes posteriorly; darker P stripe, about twice as broad as other stripes and extending onto median caudal-fin rays; blackish stripe on dorsal fin; series of 3–6 yellowish patches formed along path of I-1 by joining P and P-1 stripes.

Description. Morphometric data are in Table 1 . Body compressed and moderately elongated. Dorsal profile of head straight or slightly convex, that of body smoothly curved, slightly convex from rear of head to origin of dorsal fin, becoming straight and slightly slanted posteriorly from dorsal-fin base to caudal peduncle. Ventral profile of body convex from tip of lower jaw to anal-fin base; straight from posterior end of anal-fin insertion to caudal penduncle. Snout moderately acute in lateral view. Mouth terminal, obliquely directed upward, its articulation with upper jaw reaches slightly above middle of orbit along median axis. Head depth slightly greater than width. Maxilla and premaxillary ascending process extends much beyond horizontal axis through supraorbital margin of orbit. Presence of danionin notch on lower jaw; cleithral spot behind opercle. Infraorbital process present but incipient. Skin grooves on supraorbital shelves present. Two pairs of barbels; rostral barbel shorter than eye diameter, maxillary barbel rudimentary.

Lateral line complete with 32 (4), 33 (9) or 34 (1) pored scales. Median predorsal scales 14 (4), 15 (7), 16 (3). Lateral scale rows passing between dorsal fin and pelvic fin 8 (14). Scales along anal-fin base 11 (4), 12 (6), 13 (4). Circumpeduncular scales 12 (14).

Dorsal fin with 2 simple rays and 9 (10)–10 (4) branched rays. Anal fin with 2 simple rays and 12 (12)–13 (2) branched rays. Pectoral fin with 1 simple ray and 9 (10)–10 (4) branched rays. Pelvic fin with 1 simple ray and 7 (14) branched rays. Dorsal fin inserted at highest point midway between head and caudal-fin base. Pectoral fin inserted slightly anterior to posterior margin of opercle. Pectoral fin with moderately developed axillary lobe, pelvic-fin axillary scale longer. Caudal fin forked with lobes equal in length. Principal caudal-fin rays 10+9; procurrent caudal-fin rays: dorsally 4 (14), ventrally 3 (14).

Females with deeper body than males (29.2–31.3% SL vs. 25.2–27.25% SL). In mature female, tubercles arranged in single row on lower jaw up to origin of rostral barbel, further arranged anteriorly in random fashion ( Fig. 2 a). In mature male, tubercles are arranged in two widely separated rows on lower jaw. Outer row consists of two sub-rows ( Fig. 2 b).

Vertebrae 17+18 (2). Pharyngeal bone ( Fig. 3 ) with tooth formula 2, 3, 5, in three rows. Teeth with prominent terminal hooks, but with very narrow grinding surfaces.

Coloration. In 10% formalin, ground colour of body bright golden yellowish. Stripes and other marks on body dark brown to pale brown. Head dorsally greyish, light on side with sparse brownish dots except irregular dark brown patches at posterior region of opercle. Side of body from level of dorsal-fin origin or slightly ahead of it to caudal-fin base with three stripes: P, P+1 and P-1 ( Fig. 4 ). The stripes expand at irregular intervals anteriorly and are joined together at some points, resulting in the interruption of the I+1 and I-1 interspaces in varying degrees, organizing themselves into a series of 4–6 closely associated irregular dark bars. A series of 2–6 light yellow spots along the path of I-1 and I+1 interspaces expand or become less interrupted, resulting in thin vertical lines of light interspaces arranged alternately among the bars, which ultimately separate the bars from one another. As arranged in an irregular fashion along the anterior half of the trunk, the series of dark bars and light lines form a somewhat reticulate pattern of light and dark patches. Bars may be partly confluent with one another at different levels. In some specimens, the I+1 interspace is interrupted far ahead of the dorsal-fin origin. Stripes posterior to the dorsalfin origin become relatively uniform in arrangement with two light yellow interspaces, viz. I+1and I-1. The P stripe pigmentation increases posteriorly, extending up to the tip of the median caudal-fin rays with uniform width (about twice the width of other stripes); in its whole length, it is broader and more pigmented than P+1and P-1 stripes, extending to the end of the median caudal-fin rays (D1, D2, V1and V2); P+1 is paler, narrower posteriorly, and ceases at about the middle of the caudal peduncle. P-1 appears as a row of dark spots, narrower posteriorly, diffuse at ventral margin of P stripe at caudal fin base. I-1 interspace more distinct than I+1interspace. I-2 interspace indistinct and interrupted at intervals by the anterior expansion of P-1 stripe.

Dorsal fin has a blackish stripe from the middle of the first ray obliquely across to tips of two or three posterior rays. Scales on dorsum above the level of P+1 stripe are marked with brownish chromatophores along the exposed part of the posterior edge, forming a weak brownish crescent mark. Scales below the level of the P-1 stripe are sparsely spotted with dark brown pigments. Interradial membranes of the caudal fin are pale orange with whitish margins. The median caudal-fin branched rays (D1, D2, and V1, V2) are dark brown due to extension of the P stripe; other branched rays are sparsely scattered with brownish pigments. The anal fin is weakly pigmented basally up to the middle of the fin, ending at the last branched ray.

Distribution. Devario deruptotalea is known only from Dutah Stream (Chindwin drainage), a tributary of the Yu River, Manipur, India ( Fig. 5 ).

Habitat. The type locality has clear, shallow water measuring about 0.05 m to 1.5 m deep (during the month of March). The water is fast running with the bottom consisting of cobbles, sand and a meagre amount of mud with rich algal growth ( Fig. 6 ). Species collected with D. deruptotalea include: Barilius ngawa, Channa gachua, Garra paralissorhynchus , Garra sp., Glyptothorax ventrolineatus, Mastacembelus armatus, Neolissochilus stracheyi , Poropuntius burtoni and Schistura reticulata .

Etymology. The specific epithet is derived from Latin deruptus, meaning broken and talea, signifying bars, referring to the presence of broken colour bars on the sides of the body. A noun in apposition.

Figures

FIGURE 1. Devario deruptotalea, holotype MUMF 16001, 63.4 mm SL; India: Manipur state, Chandel District, Dutah Stream, a tributary of Yu River (Chindwin drainage).

FIGURE 2. Ventral views of head of Devario deruptotalea: a. MUMF 16008, mature female, 55.66 mm SL, showing tubercles in a single row, b. MUMF 16007, mature male, 52.87 mm SL, showing tubercles in two rows.

FIGURE 3. Devario deruptotalea, MUMF 16013, 56.7 mm SL, left side of lower pharyngeal bone in ventromedial view.

FIGURE 4. Lateral views of Devario deruptotalea showing variation in stripes: a. MUMF 16007, b. MUMF 16005, c. MUMF 16004, d. MUMF 16003, e. MUMF 16002.

FIGURE 5. Type locality of Devario deruptotalea.

FIGURE 6. Dutah Stream, type locality and habitat of Devario deruptotalea.

Tables

TABLE 1. Biometric data of holotype and paratypes of Devario deruptotalea (n = 14).

	Holotype MUMF 16001	Paratypes MUMF 16002, 16005-16014; ZSIFF 5153
Standard length (mm) % of SL	63.4	range mean SD 52.5‒63.4 57.7
Body depth Head length Head depth	29.8 23.4 18.0	25.4‒31.5 28.7 1.7 22.4‒24.3 23.0 0.8 17.2‒19.7 18.4 0.8
Head width Snout length Upper jaw length	13.0 7.2 9.2	11.6‒13.9 12.7 0.7 6.2‒7.7 6.9 0.4 8.3‒10.2 9.0 0.4
Lower jaw length Eye diameter Interorbital width	11.1 7.1 10.5	11.4‒12.0 11.5 0.4 6.5‒7.6 7.0 0.3 9.1‒11.6 9.9 0.6
Caudal-peduncle length Caudal-peduncle depth Length of dorsal-fin base	21.3 12.4 17.3	17.6‒21.4 19.5 1.1 10.8‒12.6 11.5 0.7 15.2‒19.6 16.0 1.0
Length of anal-fin base Predorsal length Preanal length	17.6 58.1 66.6	16.6‒20.3 18.3 0.8 55.6‒60.4 58.7 0.9 60.3‒67.6 65.4 0.9
Prepelvic length Prepectoral length Pectoral-fin length	46.8 23.1 19.5	43.2‒49.9 47.9 2.7 21.6‒25.0 24.2 1.6 17.7‒21.9 18.5 2.3
Pelvic-fin length	14.6	12.8‒17.2 14.8 0.6