Badis britzi, Dahanukar, Neelesh, Kumkar, Pradeep, Katwate, Unmesh & Raghavan, Rajeev, 2015

Dahanukar, Neelesh, Kumkar, Pradeep, Katwate, Unmesh & Raghavan, Rajeev, 2015, Badis britzi, a new percomorph fish (Teleostei: Badidae) from the Western Ghats of India, Zootaxa 3941 (3), pp. 429-436 : 430-434

Badis britzi , new species

( Figs. 1–3 )

Holotype. BNHS FWF 125, 32.7 mm SL, male; India: Karnataka: Nagodi tributary of the west-flowing Sharavati River, near the town of Nittur (13º54’58” N, 74º53’21”E, 594 m ASL); P. Kumkar, U. Katwate, R. Raghavan and N. Dahanukar, 30 June 2014.

Paratypes. WILD-15-PIS-140, 24.7mm SL, same data as holotype; BNHS FWF 126, 29.8 mm SL, same data as holotype (cleared and stained); ZSI-WRC P/4243, 32.2 mm SL, same data as holotype; WILD-15-PIS-141, 22.1 mm SL, same data as holotype (used for genetic analysis).

Diagnosis. Badis britzi shows a colour pattern that differs from all other species in the genus. It can be distinguished from all members of the B. ruber group ( Kullander & Britz 2002, that includes B. ruber , B. khwae and B. siamensis ) by absence of cleithral and caudal-peduncular blotches, from all members of the B. assamensis group (that includes B. assamensis and B. blosyrus ) by absence of an opercular blotch and of two parallel rows of dark blotches and alternating dark and light stripes along the body, from all members of the B. corycaeus group (that includes B. corycaeus , B pyema and B. kyar ) by the absence of an ocellus on the caudal-fin base, from all members of the extended B. badis group (that includes B. badis , B. chittagongis , B. ferrarisi , B. dibruensis , B. tuivaiei and B. kanabos ) by the absence of a cleithral blotch, and from B. singenensis by the absence of a conspicuous black blotch posterodorsally on the opercle, three distinct dark blotches on dorsal fin base and another distinct black blotch on the base of anal fin. Further, the new species also has a slender body (body depth less than 30% SL), which distinguishes it from all other congeners except B. pyema and B. kyar . Its colour pattern, which consists of 11 dark, clearly-defined bars, most closely resembles that of B. kyar and B. juergenschmidti , from which it is distinguished by a greater head length (32.3–35.0% SL vs. 26.8–31.4% in B. kyar and 28.8–29.6% in B. juergenschmidti ), a longer snout (6.8–8.3% SL vs. 5.0–6.4% in B. kyar ) and shorter dorsal-fin base (54.6–56.6%SL vs. 62.3–63.7% in B. juergenschmidti ).

Description. General appearance as in Figs. 1 and 2 , morphometric data are provided in Table 1 .

Body elongate, its depth less than 30% SL, laterally compressed. Predorsal profile convex, sharply increasing from tip of snout to anterior border of dorsal fin, then gradually decreasing from first ray of dorsal fin to end of caudal peduncle. Ventral profile descending steeply until below posterior border of eye, then almost flat to origin of anal fin, ascending thereafter to base of caudal fin. Caudal peduncle only slightly attenuated posteriorly, its length slightly more than its depth (length to depth ratio 1.1–1.2).

Head slightly pointed with angle of snout slightly less than 90° in lateral view, snout length less than eye diameter. Eyes large, situated in anterior upper half of head. Interorbital distance less than eye diameter. Mouth terminal, lower jaw projecting beyond anterior margin of upper jaw. Angle of jaws situated at vertical through anterior third of eye. Opercular spine broadly triangular, with a single tip. Vomer, palatine and pharyngeal process of parasphenoid toothed. Basihyal teeth absent. Teeth on hypobranchial 3. Gill rakers simple. First gill arch with 7 outer and 8 inner rakers on ceratobranchial and 1 outer and 1 inner raker on epibranchial region; second gill arch with 7 outer and 6 inner rakers on ceratobranchial and 1 outer and 1 inner raker on epibranchial region; third gill arch with 7 outer and 4 inner gill rakers on ceratobranchial and 1 outer and no inner gill rakers on epibranchial region; fourth gill arch with 4 outer and 2 inner gill rakers on ceratobranchial and no rakers on the epibranchial region. Ceratobranchial 5 with numerous small teeth.

Scales ctenoid on sides, cycloid on dorsal surface of head. Predorsal scales 4 anterior to coronalis pore, 9 posteriorly, excluding the pored scale. Four rows of scales on cheek. Cephalic sensory-canal pores comprise dentary pores 4 (d1-d4), anguloarticular pores 2 (aa1-aa2), preopercular pores 6 (p1, p3-p7), nasal pores 2 (n1-n4), frontal pores 3 (f2-f4), coronalis opening (cor), infraorbital pores 4 (io1-io4), lachrymal pores 3 (l1-l3), posttemporal openings 2 (pt1-pt2), extrascapular openings 3 (ex1-ex3) and pterotic opening 1 (pt2-3). Lateral line distinct, incomplete, broken into upper anterior line and posterior lower lateral line. Upper, anterior line gradually sloping until below vertical from dorsal-fin origin, then parallel to dorsal profile almost up to end of dorsal-fin base, encompassing 21(2) or 22 (3) scales. Posterior, lower lateral line with 0 (1), 1 (2) and 2 (2) pored scales, posterior lateral-line pores, wherever present, separated from anterior pores by four rows of scales. Total lateralline scale counts 22/ 2 in holotype and 21/1, 22/1, 21/2 and 22/0 in paratypes. Scales in longitudinal series, including those on base of caudal fin, 26 (1), 27 (1) or 28 (3). Scales in transverse series ½2/1/7. Circumpeduncular scales 16.

Vertebrae 15+13 ( Fig. 3 ) in c&s specimen. Dorsal-fin rays XVII+9 (5). Anal-fin rays III+7 (5). Pectoral-fin rays 12 (1) or 13 (4). Pelvic-fin rays I+5 (5). Principal caudal-fin rays 7+7 (5). Procurrent caudal-fin rays 3+3 (5). Sheathing scales present along base of dorsal and anal fins.

Interradial membranes of spinous dorsal fin projecting as short fin lappets that do not extend much beyond tips of spines. Soft dorsal and anal fins with rounded tips, extending to base of caudal fin or slightly beyond. Pectoralfin origin on vertical through first dorsal-fin spine, adpressed pectoral-fin reaching posteriorly to vertical through base of 9th or 10th dorsal-fin spine. Pelvic-fin with its origin on vertical through third dorsal-fin spine, adpressed pelvic-fin reaching posteriorly to 13th or 14th dorsal-fin spine, stopping short of anal-fin base. Caudal fin subtruncate.

Coloration in life. General appearance as in Figure 2 . Background colour beige to light brown, darker on dorsal than on ventral side, with several reddish and dark-brownish to black marks. Preorbital stripe dark brown. Postorbital stripe dark brown, extending obliquely from upper posterior margin of eye towards nape. No cleithral spot. A series of 11 irregular dark bars on lateral surface of body and tail base, consisting of a mosaic of darkbrown and red pigments. Caudal blotch absent, but end of caudal peduncle with a vertical black bar followed by a red vertical bar towards base of caudal fin. Pectoral fin translucent. Pelvic-fin outer rays with black interradial membrane, inner rays with red pigmentation. Anal fin dusky at base, with intermittent black and red pigments. Dorsal-fin base with dense aggregations of melanophores forming blotches along its base, mostly continuing from bands on lateral side of body. Seven such blotches on base of dorsal fin. Base of each dorsal-fin spine dusky, distal ends white. Dorsal fin membrane dusky at the base, followed distally by a band of red chromatophores. Base of dorsal-fin soft rays with melanophores and brown chromatophores, distal area mainly translucent, with occasional red chromatophores. Caudal fin, translucent, without pigmentation except for a dark-brown and red band at its base.

Colour in preservative. Similar to coloration in life. Background body colour more uniform dark brown. Black bars more clearly visible posterior to anterior border of anal-fin base. Red melanophores less conspicuous. Coloration on caudal base less conspicuous.

Distribution. Badis britzi is currently known only from its type locality in the Nagodi tributary of the westflowing Sharavati River, near the town of Nittur, Karnataka, India ( Fig. 4 ).

Etymology. The species name honours Ralf Britz, Natural History Museum, London, for his contributions to the understanding of the systematics and evolution of badid fishes.

Habitat. The species was found in a slow-moving clear stream with riparian cover ( Fig. 5 ), with gravel and pebbles as the major substrate. The species was found associated with marginal vegetation and submerged roots. Co-occurring fishes included Barilius sp., Devario malabaricus , Danio rerio , Schistura nagodiensis , Haludaria fasciata , Dawkinsia arulius , Pethia sp., Channa gachua and Mastacembelus armatus .

Genetic distance. Badis britzi ( KP666031 ) has a significant genetic distance in COI gene (P distance = 16.7±1.6) from Badis badis ( KP666032 , collected from Mysore, Karnataka), the only other species within the genus that occurs in southern India.

Figures

FIGURE 1. Badis britzi, holotype (BNHS FWF 125, 32.7 mm SL).

FIGURE 2. Badis britzi, holotype in life, immediately after capture.

FIGURE 3. Cleared and stained specimen of Badis britzi, paratype (BNHS FWF 126, 29.8 mm SL).

FIGURE 4 Type locality of Badis britzi in the west-flowing Sharavati River, Karnataka, India.

FIGURE 5. Habitat at the type locality of Badis britzi: the Nagodi tributary of Sharavati River, Karnataka, India.

Tables

TABLE 1. Selected morphometric information of type series of Badis britzi (n = 5, holotype BNHS FWF 125 and paratypes WILD- 15 - PIS- 140, BNHS FWF 126, ZSI-WRC P / 4243 and WILD- 15 - PIS- 141).

Character	Holotype	Mean (sd) (n=5) Range (n=5)
Total length (mm) Standard length (SL, mm)	BNHS FWF 125 39.3 32.7	34.4 (5.4) 27.4–39.3 28.3 (4.7) 22.1–32.7
% SL Head length (HL) Snout length	33.9 6.8	33.6 (1.0) 32.3–35.0 7.3 (0.6) 6.8–8.3
Eye diameter Interorbital width Upper-jaw length	9.7 8.3 9.1	9.6 (0.7) 8.7–10.6 7.9 (0.4) 7.5–8.3 7.4 (1.1) 6.1–9.1
Lower-jaw length Body depth Pelvic fin-length	10.1 27.1 26.7	9.3 (0.6) 8.4–10.1 26.9 (1.0) 25.5–28.4 25.9 (0.7) 24.9–26.7
Pelvic to anal distance Dorsal-fin base length Anal-fin base length	27.6 56.1 17.5	30.6 (2.0) 27.6–32.8 55.9 (0.8) 54.6–56.6 17.9 (2.6) 16.2–22.5
Caudal-peduncle depth Caudal-peduncle length % HL	15.4 16.6	14.7 (0.5) 14.2–15.4 16.1 (0.7) 15.3–17.0
Snout length Eye diameter	20.1 28.5	21.8 (1.5) 20.1–23.8 28.5 (1.3) 27.1–30.4