Badis dibruensis, a new species (Teleostei: Badidae) from northeastern India

Kh. Geetakumari1 & W. Vishwanath2

1,2Department of Life Sciences, Manipur University, Canchipur,Imphal, Manipur 795003, India

Email: 1 geetameme@gmail.com, 2 wvnath@gmail.com (corresponding author)

Date of publication (online): 26 January 2010

Date of publication (print): 26 January 2010

ISSN 0974-7907 (online) | 0974-7893 (print)

Editor: Rema Devi

Manuscript details:

Ms # o2156

Received 10 March 2009

Final received 14 August 2009

Finally accepted 05December 2009

Citation: Geetakumari, Kh. & W.Vishwanath (2010). Badis dibruensis, a new species (Teleostei:Badidae) from northeastern India. Journal of Threatened Taxa 2(1): 644-647.

Copyright: © Kh. Geetakumari & W. Vishwanath 2010. Creative Commons Attribution 3.0 UnportedLicense. JoTT allows unrestricted use of this article in any medium for non-profit purposes, reproduction and distribution by providing adequate credit to the authors and the source of publication.

Author Details: Kh. Geetakumari is a research scholar in the Department of Life Sciences, Manipur University. She is pursuing research in Phylogeneticstudies of fishes belonging to the order Perciformesfound in northeastern India under the supervision of W. Vishwanath.

W. Vishwanathis a professor in the Department of Life Sciences, Manipur University. His field of specialization is Fish and Fisheries. He is at present engaged in taxonomy and systematics of freshwater fishes of northeastern India

Author Contribution:The study: Kh.G Undergoing research in the Perciformes fishes of northeastern India. WV Supervision of taxonomy and phylogeny of freshwater fishes of northeastern India. Current paper: As a part of the research work, all the badid fishes of the region have been studied and the species is found to be new. Supervised the work and helped in identifying the species.

Acknowledgements:The first author is grateful to Manipur University for award of UGC research scholarship and the second, to Ministry of Environment and Forests, Govt. of India for financial assistance (Project No. 14/11/2006-ERS/RE). We thank Mr. Santosh for the collections.

Abstract:A new species of the genus BadisHamilton is described from Dibru River, Dibrugarh, Brahmaputra basin in Assam, India. The species has the following combination of characters: a conspicuous black blotch covering the superficial part of the cleithrum above pectoral fin base, a small oval-shaped black blotch on the middle of caudal fin, two predorsalbones, interorbital width 9.9-15.0, upper jaw length 6.1-6.9, lower jaw length 7.1-8.3 and orbital diameter 7.6-9.4 % SL. The species differs from its nearest congeners, B. badis, B. kanabos and B. tuivaiei by the absence of dark black or brown vertical bars on sides. A key to species of Badis of India is provided.

Keywords: Assam, Brahmaputra basin, new fish, Perciformes

For Figure, Images and Tables

Introduction

Hamilton (1822) described Labrus badisand L. dario from Gangetic provinces. Bleeker(1854) established genus Badis for L. badis under family Nandidae. Barlow et al. (1963) erected a new family, Badidae, in which Badishas been incorporated based on osteologicalcharacters. The genus is separated from the nandid genus Nandusin having a smooth (versus serrated) preopercularmargin and edentulous (versus toothed) tongue. As per Kullander & Britz(2002) the genus is characterized by a combination of the following features: opercle with a single sharp spine at its posterodorsal corner; spinous and soft dorsal fins contiguous, the base of the soft part longer than that of the spinous part; anal fin with three spines; lateral line pores tubed and interrupted; jaws, vomer and palatines with villiformteeth; scales both ctenoid and cycloid; 2-4 dentary foramina; hypobranchial 3-toothed; males with short pelvic fin, not reaching the first dorsal spine; short dorsal fin lappets; rounded caudal fin.

Ahl (1937) described Badis badis assamensis from Assam, while Talwar & Jhingran (1991) did not recognize any subspecies of B. badis. Kullander & Britz (2002) treated B. assamensisas a valid species and designated a neotype. They also described B. blosyrusand B. kanabos from Brahmaputra basin, Assam and B. ferrarisi from Myanmar. Vishwanath & Shanta (2004) described B. tuivaieifrom Tuivai River in Brahmaputra basin. Vishwanath et al. (2007) also recorded B. ferrarisi from Chindwin basin in Manipur. Thus, six species of Badis are currently recognized from northeast India.

During field surveys in northeast India in 2006 and 2007, specimens of an undescribed Badis were collected from Dibru River, Dibrugarh, Brahmaputra basin, Assam. The species is herein described as Badis dibruensis sp. nov.

Materials and Methods

Measurements were made point to point with dial calipers to the nearest 0.1mm and expressed as percentages of standard length (SL). Counts and measurements were made on the left side of specimens under a PC-based binocular stereo zoom microscope (Olympus SZ40) with transmitted light. Counts and measurements followed Kullander & Britz(2002). The method of clearing and staining of specimens for osteology follows Hollister (1934). Identification and nomenclature of bones and vertebral counts follows Greenwood (1976). For branchial toothplate count, the first gill arch on the left side of the specimens was taken, and plates starting from hypobranchialto epibranchial of the outer side were counted. Type specimens are deposited in the Manipur University Museum of fishes (MUMF).

Badis dibruensis sp. nov.

(Images 1 & 2)

Type material

Holotype: 37.3mm SL, 16.iii.2006, 27°32’09.98”N & 94°58’02.31”E, Dibru, Brahmaputra drainage, Dibru River, Dibrugarh, Assam, India; coll. Santosh, MUMF-Per 95.

Paratypes: MUMF-Per 96-110, 15, 23.0-40.8mm SL, data as for holotype; MUMF Per-108-110, 3, dissected, cleared and stained for osteology.

Diagnosis

Badis dibruensis sp. nov. is distinguished from its nearest congener, B.badis in having two (vs. three) predorsal bones; small oval (vs. large rectangular) black blotch in the mid-base of caudal fin; more interorbitalwidth (9.9-15.0 vs. 6.5-8.3% SL); shorter upper jaw (6.1-6.9 vs.8.2-10.2% SL) and lower jaw (7.1-8.3 vs. 11.3-14.5% SL). It is distinguished from B. kanabos in having smaller eye diameter (7.6-9.4 vs. 9.5-12.7% SL). It is also distinguished from B. tuivaiei in having vertebrae 27 (vs. 31); more interorbital width (9.9-15.0 vs. 5.6-7.2% SL); shorter upper jaw (6.1-6.9 vs. 8.5-10.4% SL). B.dibruensis differs from all three mentioned species by the absence (vs. presence) of dark black or brown vertical bars on sides.

Description

Morphometric data and counts are in Tables 1 & 2, respectively. Frequency distributions of meristic characters are provided in Table 3 and comparison with related species in Table 4. Body elongate, moderately compressed laterally. Predorsal profile in small specimens straight, sloping at some angle as of prepelvic profile in larger specimens and more strongly as the size increases. Orbit situated in anterior half of head, at about mid-lateral axis of body. Jaws almost equal anteriorly, lower jaw slightly projecting, maxilla reaching to 1/3 of orbit. Opercular spine slender, with a sharp tip. Palatine, vomer andparasphenoid toothed.

Pores: dental 3,anguloarticular 2, preopercular6, nasal 6, supraorbital 3, extrascapular5, supracleithral 2, posttemporal2, coronalis 1, lachrymal 3, infraorbitalpores 3-4. A row of free neuromasts extending across gap between lachrymal and anteriormost infraorbital.

Scales strongly ctenoid on sides, cycloid on top of head. Predorsal scales anterior to coronalis pore 4-5, posteriorly 8-9. Scales on cheek 3, mostly ctenoid, a few scales anterior to cheek cycloid. Circumpeduncular scale rows 10 above, 10 below lateral line, totaling 22. Scales in vertical row 1½ above, 7 below lateral lines. Vertebra 27 (15/12).

Soft dorsal and anal fins with rounded tips reaching to almost about 1/3 or 1/4 of caudal fin. Caudal fin rounded. Pectoral fin rounded, extending about 2/3 distance to anal-fin origin. Pelvic fin pointed, inner branch of second soft ray longest, not reaching up to vent. Orbital diameter, interorbital width and upper jaw length respectively (7.69.4), (9.9-15.0) and (7.1-8.3) % SL.

Colouration

In 10% formaline, overall dark brownish to yellowish. Preorbitalstripe dark grey, continued across chin; postorbital stripe blackish, formed by a single blotch close to orbit; dark pigment also on one scale posterior to that blotch. No supraorbital stripe. A conspicuous black blotch covering the superficial part of the cleithrum above pectoral-fin base. Dorsal fin dusky. Dorsal lappets white along distal margin, bordered by blackish submarginal stripe in male. Caudal fin with a small oval black blotch at middle of base, also covering last lateral scale on body. Anal fin dusky basally, soft part hyaline throughout in large specimens. Pelvic fin dusky in small specimens, dark brown in large specimens. Vertical dark black or brown bars are completely absent across the side and caudal peduncle.

Sexual dimorphism

Males have uniform dark brown fins with white dorsal fin lappets along distal margin, bordered by blackish submarginal stripe. Extension of the posteriormost tip of the dorsal fin extends upto 1/2 of the caudal fin.

In females, body pale yellow with dark grey spots, fins with uniform light brown coloration. Extension of the posterior-most tip of dorsal fin extends upto 1/3 of the caudal fin.

Etymology

Named after the Dibru River, the type locality.

Distribution

Presently known from Dibru River at Dibrugarh, Assam, Brahmaputra drainage (Fig. 1)

Discussion

Badis dibruensis is similar to B. badis, B. kanabos and B. tuivaieiin having a conspicuous dark blotch covering the superficial part of cleithrum above pectoral-fin base. However, the species differs from them in morphometric characters as in diagnosis above. B. dibruensis is distinct from B. assamensis and B. blosyrus, other two congeners of Brahmaputra basin in absence (vs. presence) of blotch on opercle.

Five species of Badis, viz., B. corycaeus, B. ferrarisi, B. kyar, B. pyema and B. ruberare known from Irrawaddy drainage (Kullander & Britz 2002). The new species differs from B. kyar, B. corycaeus B. pyema in the presence (vs. absence) of cleithral blotch; from B.ruber in absence (vs. presence) of a dark black blotch on dorsolateral aspect of caudal peduncle. It also differs from B. ferrarisi in absence (vs. presence) of the vertical bars across side and caudal peduncle.

Badis dibruensis also differs from B. siamensis and B. khwaerespectively of Takaupa River basin and Mae Nam Khwae Noi drainage, Thailand in absence (vs. presence) of a dark blotch on dorso-lateral aspect of caudal peduncle; from B. chittagongis ofMatamohuri River drainage, Bangladesh, in absence (vs. presence) of the vertical bars across side and caudal peduncle.

Kullander & Britz (2002) classified the species of Badisinto five groups viz., B. rubergroup, B. assamensis group, B. corycaeus group, B. kyargroup and B. badis group. The species of B. badisgroup share a cleithral blotch. They expected more number of species in B.badis group from the view i.e. the limited material from India, variable characters and scattered locality record of the species. The present species under diagnosis belongs to B. badis group.

Out of the known 13 valid species of Badis, six is reported from northeast India. In addition to this the present species under study is also from the Brahmaputra basin. General inventory and phylogenetic study of the diverse species of Badis in northeast India and adjoining areas would be of great interest.

Comparative materials

Badis assamensis: MUMF Per-51-54, 4, 41.6-55.8 mm SL, Dibru River, Dibrugarh, Assam, India; B. badis: MUMF Per-55-65, 11, 23.5-28.7 mm SL, Barak River, Manipur, India; B. blosyrus: MUMF Per-66-68, 3, 36.8-38.9 mm SL, Teju River, Teju District, Arunachal Pradesh, India; B. ferrarisi: MUMF Per- 69-75, 7, 32.0-44.0 mm SL, Lokchao River, Manipur, India; B. kanabos: MUMF Per-76-81, 6, 48.7-54.9 mm SL, Barak River; Manipur, India; B. tuivaiei: MUMF 5125-5132, 8, 53.5-59.4 mm SL, Tuivai and Irang River, Manipur, India.

References

Ahl, E. (1937). Neue susswasserfische aus dem Indischen und Malaiischen Gebiet. Zoologischer Anzeiger 117: 113-119.

Barlow, G.W., K.F. Leim & W. Wickler(1968). Badidae, a new fish family- behavioural, osteological, and development evidence. Journal of Zoology 156: 415-447.

Bleeker, P. (1854). Nalezingen op de ichthyologischefauna van Bengalen en Hindostan.Verhandeligen van het Bataviaasch Genootschap van Kunsten en Wettenschappen 25(8): 1-166.

Greenwood, P.H. (1976). A review of the family centropomidae(Pisces, Perciformes). Bulletin of the British Museum (Natural History) 29(1): 1-81.

Hamilton, F. (1822). An Account of the Fishes found in the River Ganges and Its Branches.Archibald Constable and Company, London, 405pp + 39pls.

Hollister, G. (1934). Clearing and dyeing fish for bone study. Zoologica 12: 89-101.

Kullander, S.O. & R. Britz (2002). Revision of the family Badidae (Teleostei: Perciformes), with description of a new genus and ten new species. Ichthyological Exploration of Freshwaters13(4): 295-372.

Talwar, P.K. & A.G. Jhingran (1991). Inland Fishes of India and Adjacent Countries. Oxford and IBH Publishing Co. Pvt. Ltd., New Delhi, 2 volumes, xix + 1158pp.

Vishwanath, W. & K. Shanta (2004). A new fish species of the Indo-Burmese genus Badis Bleeker (Teleostei: Perciformes) from Manipur, India. Zoos’ Print Journal19(9):1619-1621.

Vishwanath, W., W.S. Lakra & U.K. Sarkar(2007). Fishes of North East India. National Bureau of Fish Genetic Resources, Lucknow, UP, India, 264pp.