Badis pallidus, Kullander & Norén & Rahman & Mollah, 2019

Kullander, Sven, Norén, Michael, Rahman, Md. Mizanur & Mollah, Abdur Rob, 2019, Chameleonfishes in Bangladesh: hipshot taxonomy, sibling species, elusive species, and limits of species delimitation (Teleostei: Badidae), Zootaxa 4586 (2), pp. 301-337 : 319-322

Badis pallidus , new species

( Fig. 9 )

Holotype. DU 9038 , male, 38.7 mm SL. Bangladesh: Chittagong Division: Bandarban District: Sangu River drainage: Shailopropat Waterfall and downstream pools. 22°9′6″N, 92°12′59″E; M.M. Rahman et al., 14 May 2015 (SRL-2015-029).

Paratypes. All from Bangladesh, Chittagong Division: Karnafuli River drainage: DU 6189 , 2 , 25.7 – 28.8 mm SL; Khagrachori District , Chengi River in Khagrachori , 23°6′8"N, 91°58′45"E; M.M. Rahman, 24 Apr 2015.— DU 6243 , 1 ; Khagrachori District , Taichala stream, 23°6′14"N, 91°58′1"E; M.M. Rahman, 26 Apr 2015.— NRM 67718, 2 , 14.9 – 16.2 mm SL; Rangamati District : Kamila stream, tributary to Karnafuli River , 22 km south of Rangamati , 22°31′41″N, 92°11′55″E; M.M. Rahman et al., 28 Nov 2014 (SRL-2014-006).— NRM 67780, 1 ; NRM 67781, 1 ; NRM 68029, 1 , 13.5 mm SL; Bandarban District : Udalbania: small stream left bank tributary to Karnafuli River , flowing through tobacco plantation, 22°19′28″N 92°8′20″E; M.M. Rahman, 12 May 2015 (SRL- 2015-019).— Halda River drainage: NRM 66773, 1 ; Chittagong District: roadside ditch in Sultanpur, 22°32′32″N, 91°53′59″E. 29; M.M. Rahman et al., Nov 2014 (SRL-2014-010).— NRM 66816, 1 ; Chittagong District: hillstream at northwestern margin of Chittagong University campus, in and below rapids, 22°28′26″N, 91°46′59″E; M.M. Rahman et al., 29 Nov 2014 (SRL-2014-011).— NRM 66789 1, 26.0 mm SL; NRM 66790, 1 , 26.8 mm SL; NRM 66791, 1 , 30.2 mm SL: NRM 66792, 1 , 10.6 mm SL; NRM 67748, 13 , 17.4 – 39.2 mm SL; Chittagong District: stream at southeastern margin of Chittagong University campus, tributary to Halda River ; 22°27′37″N 91°47′48″E; M.M. Rahman, 29 Nov 2014 (SRL-2014-012).— Sangu River drainage: DU 6005 , 3 , 28.2 – 33.3 mm SL; Bandarban District , Sangu River : Shaila Propat Waterfall, 22°9′6″N, 92°12′59″E; M.M. Rahman, 5 May 2015.— NRM 69436, 1 , 36.9 mm SL; NRM 69437, 1 ; NRM 69438, 1 ; Bandarban District : Shailopropat hillstream, 22°9′6″N, 92°12′59″E; M.M. Rahman, 13 Feb 2016 (MMR- 2016-FEB13).— NRM 67308, 1 , 33.4 mm SL; NRM 67309, 1 , 32.4 mm SL; NRM 68217, 10 , 27.2 – 32.7 mm SL; NRM 68096, 12 , 26.3 –39.0 mm SL; Bandarban District : optopat Waterfall and downstream pools, 22°9′6″N, 92°12′59″E; M.M. Rahman et al., 14 May 2015 (SRL-2015-029).— NRM 67251, 1 23.8 mm SL; Bandarban District : Dopachari Stream in Dudpukuria Dopachari Wildlife Sanctuary , 22°13′40″N 92°7′32″E; M.M. Rahman et al., 13 May 2015 (SRL-2015-023).— NRM 67273, 1 , 22.8 mm SL; NRM 67274, 1 ; NRM 67275, 1 ; NRM 67276,1 ; NRM 67277, 1 ; NRM 67278, 1 ; Bandarban District : Myani Stream in Dudpukuria Dopachari Wildlife Sanctuary , 22°14′42″N, 92°6′57″E; M.M Rahman et al., 13 May 2015 (SRL-2015- 024).— NRM 68180, 1 , 34.8 mm SL; Bandarban District : Sangu River at Dhopachari, 22°12′22″N 92°8′2″E; M.M. Rahman et al., 3 May 2015 (SRL-2015-025).— NRM 67670, 1 , 23.5 mm SL; NRM 67671, 1 , 25.1 mm SL; NRM 68104, 2 , 25.2 -26.0 mm SL; Bandarban District : Ruma : small stream tributary to Sangu River , under bridge near Munlai Para village , east of Ruma , 22°1′58″N, 92°25′3″E; M.M. Rahman et al., 14 May 2015 (SRL-2015-028).— NRM 67949, 1 ; 67950, 1, 24.0 mm SL; NRM 68183, 3 , 21.1 – 24.1 mm SL; Bandarban District : Ruma : Mrong Bazar, small stream tributary to Sangu River , below bridge. 22°3′27″N, 92°18′56″E; M.M. Rahman et al., 14 May 2015 (SRL-2015-026).— NRM 68169, 1 , 24.0 mm SL; Bandarban District : Kokhiyon Jhiri stream, 11 km W of Ruma, 22°3′29″N 92°20′31″E; M.M. Rahman et al., 14 May 2015 (SRL-2015-027) .

Diagnosis. Similar to B. badis , B. chittagongis , B. ferrarisi Kullander & Britz, 2002 , B. kanabos , B. khwae Kullander & Britz, 2002 , B. pallidus , B. ruber Schreitmüller, 1923 , B. siamensis Klausewitz, 1957 , B. soraya Valdesalici & van de Voort, 2015 , B. tuivaiei Vishwanath & Shanta, 2004 , and different from all other species of Badis in the presence of a dark blotch on exposed cleithrum. Distinguished from B. khwae , B. ruber , and B. siamensis , by the absence of a dark blotch dorsolaterally on the caudal peduncle. Distinguished from B. ferrarisi by the absence of short black bars along the middle of the side, and the absence of a dark blotch on the gill cover. Distinguished from B. tuivaiei in the absence of a black blotch anteriorly on dorsal fin, and lower meristic values (28–29 vertebrae vs. 30–31, lateral scale row 27–29 vs. 26–32, modally 30; dorsal-fin rays XVI.8½ (1), XVI.9 (9), XVII.8½ (4), XVII.9 (2) vs. XVI.9–10, XVII.8, XVIII.8 and modally XVIII.9); from B. kanabos by the absence of a black spot anteriorly on the dorsal fin; from B. badis by narrower interorbital space (4.6–6.3% SL vs. 6.5–8.3%, not corrected for allometry); from B. soraya and B. rhabdotus by the absence of intense black narrow vertical bars on the sides in males, vs. presence; from B. chittagongis in paler colour, 6 vs. 7 scales between the anal fin and upper lateral line, and 15–17 vs. 16–20 circumpeduncular scale rows.

Description. Proportional measurements are given in Table 4 ; selected meristics in Tables 6–7. Moderately elongate, strongly compressed laterally. Predorsal contour straight or slightly curved, sloping at same angle as slightly curved prepelvic contour. Orbit situated in anterior half of head and level of midaxis of body. Jaws about equal anteriorly, lower jaw only slightly projecting before upper; maxilla reaching slightly posterior of vertical through anterior margin of orbit. Lower jaw articulation below middle of orbit. Some females distinguished by bulging abdomen, and then also generally fainter fin pigmentation and shorter pelvic and soft dorsal and anal fins.

Dentary pores 3, anguloarticular pores 2, preopercular pores 7, nasal pores 2, supraorbital pores 3, extrascapular pores 2, supracleithral pores 2, posttemporal pores 2, coronalis pore 1, lachrymal pores 3 extending across gap between lachrymal and anteriormost infraorbital, 3-4 infraorbital pores. Scale rows on cheek 4, on opercle 4, on preopercle 1, on interopercle 1.

Scales in lateral row 26 (4), 27 (7), 28 (3). Lateral-line scales 17/2 (1), 20/0 (1), 20/1 (2), 20/6 (1), 21/3 (1), 22/ 2 (2), 22/3 (4), 22/4 (1), 23/0 (1), 23/1 (1), 23/4 (1). Circumpeduncular scale rows 16 (17). Predorsal scales 10 (1), 11 (5), 12 (7), 13 (3). Scales between first dorsal fin-spine and upper lateral line 3, posteriorly 1½ scales between dorsal-fin base and upper lateral line. Full-size scales between first anal-fin spine and upper lateral line 6 (17). From about fifth dorsal-fin spine, dense layer of small elongate scales, 2–3 on each interradial space, covering spinous dorsal-fin base up to at most middle of fin height; on base of soft dorsal fin, scales smaller and rounded. Anal fin from behind second spine to anterior soft rays with narrow layer of small, slightly elongated or rounded scales, 1–3 in each interradial space. Caudal fin with narrow basal cover of about 3–4 larger scales, beyond that narrow layer of smaller interradial scales, about 4–5 on each membrane.

Dorsal-fin rays XVI.8½ (1), XVI.9 (9), XVII.8½ (4), XVII.9 (2). Soft anal-fin rays 6½ (4), 7½ (9), 8½ (3). Soft dorsal and anal fins with rounded or subacuminate tip, reaching to one-third of caudal fin or slightly shorter, or only little beyond caudal-fin base, respectively. Caudal fin rounded. Pectoral-fin rays 11 (4), 12 (8), 13 (4). Pectoral fin rounded, not reaching posteriorly to tip of pelvic fin. Pelvic fin with point formed by second soft ray, not reaching halfway to second anal-fin spine.

Ceratobranchial gill rakers 6 (3), 7 (4), 8 (7), 9 (1), 10 (1). Supraneurals 3 (9), vertebrae 14+13=27 (2), 14+14=28 (6), 15+13=28 (1), 15+14=29 (1).

Colouration in preservative. Ground colour pale beige. Postorbital stripe composed of black spots covering two or three scales in oblique row posterodorsally from orbit at about 1400h position. Dark grey or black suborbital and preorbital stripes. Tip of maxilla white. Top of head medially dark brown. Black spot with narrow white lining covering exposed part of cleithrum. Young specimens and females with indistinct oblique stripe from base of first dorsal-fin spine, across gill cover; on sides five pairs of dark brown vertical bars, each formed by dark spots on scales; bars in each pair well-spaced, rarely interspace pigmented to form a broad vertical bar with darker anterior and posterior margins. Posterior two bar-pairs, on caudal peduncle and above anal fin reaching dorsal and ventral margins of body, anterior pairs not continued onto abdominal sides. Large males with vertical bars indistinct or absent; sides uniformly grey with dark scale bases and light scale margins. Dorsal-fin lappets with narrow white distal margin and narrow black submargin, rest of interradial membrane grey; soft fin pale greyish, semitransparent. Row of grey spots along middle of spinous dorsal fin, immediately distal to basal scale cover, frequently present. Caudal fin with median round or slightly horizontally extended dark brown blotch, in some specimens a wide dark band across caudal peduncle sides, obscuring caudal blotch, or dark blotches present at middle and at upper and lower margin of caudal-fin base.

Etymology. Named pallidus , a Latin adjective meaning pallid, pale, in reference to the uniform light grey body colour of males of this species.

Geographical distribution and habitats. Badis pallidus , which has a wide distribution in the Karnafuli and Sangu Rivers, was collected in small hillstreams ( Figs 3 , 10 ). At Shailopropat Falls, specimens were collected downstream of the falls where the slope lessened, and not at the foot of the falls.

Figures

FIGURE 3. Collecting sites of species of Badis and Dario in Bangladesh.

FIGURE 9. Badis pallidus. A, holotype, adult male, DU 9038, 38.7 mm SL], Sangu River: Shailopropat Falls; B, paratype adult female, NRM 68217, 32.7 mm SL, Sangu River: Shailopropat Falls; C. paratype, NRM 67748, adult male, 36.3 mm SL, Bangladesh: Halda River tributary stream, Chittagong University Campus.

FIGURE 10. Shailopropat Falls in the dry season, looking down from above the middle of the falls. Badis pallidus was collected from the small stream at the bottom of the ravine.