A new report of Horabagrus brachysoma Jayaram, family Bagridae in Uttara Kannada District, Karnataka

3 Pages·2001·1.8 MB·

by  Anuradha Bhat

MISCELLANEOUS NOTES
24. ANEW REPORTOFHORABAGRUSBRACHYSOMA JAYARAM,
FAMILYBAGRIDAEINUTTARAKANNADADISTRICT,KARNATAKA
(With one text-figure)
The catfish Horabcigrus brachysomci rayed fin with 5-7 rays, possesses a hard spine
Jayaram, Family Bagridae, has been reported in and is separated from the softer smaller adipose
the Kerala Western Ghats. Itwas firstdescribed dorsal fin. It also has four pairs ofbarbels: one
as Pseudobagrus brachysomci by Gunther in nasal, two mandibular and one maxillary.
1864,andbyDayin 1865 (Proc.zool. Soc. Lond. (Jayaram 1981)
p. 290, Malabar, ii, p. 185, pi. xiii, fig. 2), from This species has, till date, been reported
Cochin as Pseudobagrus chryseus. In later from Neyyatinkara backwaters (near
publications,Day(1889)referstoitasMacrones Trivandrum), its southernmost limit, to regions
chiyseus. ThespeciesofthegenusMacronesare near the Karnataka border, the northernmost
identical to the Indian species of Mystus. They limit.
are characterised by the presence of 15 or less Field surveys were conducted in the river
anal finrays, eyes placed much above the angle systems of Uttara Kannada district, located in
ofthemouth(invisiblefromtheventralsurface), northern Karnataka. Uttara Kannada (13° 52' to
barbels longerthanhead, the pelvic fin far from 15°30'Nand74°5'E), formspartofthenorthern
the anal fin, and a moderately long adipose fin. extentoftheWesternGhats(Fig. 1). Thisregion
On the other hand, M. clvyseus is characterised has many perennial and temporary streams and
by the presence ofan anal fin with 26-28 rays, rivers. The fish diversity ofthe four main west
the eyes being placed in line with the angle of flowing rivers, Sharavati, Aghanashini, Bedti
the mouth so that it is visible from the ventral and Kali, were studied. Collections were made
surface, the barbels not extending beyond the using gill nets, cast nets and drag nets. Samples
head and the pelvic fin reaching the anal fin. werecollectedfromsixsitesineachofthesefour
Because ofthese anomalies, M. chiyseus rivers from January 1997 to January 1999.
was separated from the Mystus group and for During a recent survey, fresh samples of
some time, it was placed in the genus Horabagrus brachysoma have been collected at
PseudobagrusasP. brachysoma(Jayaram 1952). the rivers Kali and Aghanashini near the
P. brachysoma is the only species ofthe genus downstreamreaches ofthese river systems. The
from the Indian subcontinent, while the other species (H. brachysoma) in the River Kali was
species ofthe genus are Chinese. A comparison first recorded at Kadra (74° 20’ E, 14° 53' N,
m
of specimens of P. brachysoma with other about 100 above msl). The habitat at this site
specimensofPseudobagrusshowedthattheyare consists of smooth flowing runs, the riparian
not congeneric, so P. brachysoma was given a vegetationhereismostlycomposedoflongstands
new generic rank and named as Horabagrus ofbambooandspeciesofTerminalia.The siteat
(Jayaram 1955). Kadra is very close to the Kaiga Dam Project
The species Horabagrus brachysoma has and forms part ofthe reservoir. As a result, the
amoderatelyelongated,compressedbodywitha water here is regulated. Local villagers revealed
large head and a wide subterminal mouth. The that the species is found in this region, but is
eyes are large, inferior and visible from the rarer than other Bagrids. The first collections
ventral side. The dorsal fin, consisting of the were made in March 1998. In April 1998, we
294 JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 98(2), AUG. 2001
.
MISCELLANEOUS NOTES
Horabagrus listed as endangered, has
,
beenrecordedearlieronly in Kerala. This report
on the presence of Horabagrus brachysoma in
Uttara Kannada is important since itextends the
known geographical range from Kerala to
regions much further northwards along the
Western Ghats. Though it has not yet been
reported from southern Karnataka, our findings
suggestthepossibleoccurrenceofthespeciesall
along the hill streams ofthe Western Ghats.
Table
1
MORPHOMETRICDETAILSOF
THESPECIMENS(INCM)
Parameter Specimen Specimen Specimen
measured fromKadra from fromKadi's
Kirtigadde
Totallength 14.4 19.9 21.2
Standardlength 11.8 16.2 17.4
Headlength 3.2 4.2 4.8
Bodydepth 3.1 4.5 5.2
Lengthofsnout 1.2 1.9 2.1
Eyediameter 0.65 0.9 1.0
Interorbitaldistance 1.8 2.6 3.0
Lengthofbarbel:
nasalbarbel 1.6 2.1 2.3
maxillarybarbel 2.1 2.8 2.4
outer
mandibularbarbel 2.2 25 2.6
Uttara Kannada District, Karnataka innermandibular
barbel 1.2 1.7 1.8
collected one more specimen from the Predorsaldistance 4.2 6.4 6.5
downstream reaches ofthe riverAghanashini at Postdorsaldistance 7.8 9.5 11.2
Distancefrom
Hulidevarakodlu (74° 40' E, 14° 24' N, about
m pectoralfinbase
500 above msl). The River Aghanashini is topelvicfinbase 3.9 4.2 4.5
subjected to much less human disturbance than Distancefrom
the River Kali. The study area near pelvicfinbase
toanaltinbase 1.0 1.4 11.4
Hulidevarakodluispristine,withthickevergreen Lengthof
forests of Terminalia Eugenia hyneana caudalpeduncle 1.6 2.3 2.2
, ,
Callophyllum spp., Mangifera indica, and Heightof
caudalpeduncle 1.3 1.9 2.0
Pongamia forming the riparian vegetation.
Heightof
Two more specimens were collected in dorsaltin 1.8 3.6 3.7
January 1999, one at the same site on the River Lengthof
Kali (at Kadra) and one at Kirtigadde (74° 36.5' pectoraltin 2.5 3.1 3.6
E, 14°26'N,about500mabovemsl), 1 kmdown- pLeelnvgitchtionf 1.5 2.1 2.2
stream of Hulidevarakodlu. The morphometric Lengthof
details ofthe specimens are giveninTable 1 analtin 2.8 4.1 4.6
JOURNAL. BOMBAYNATURAL HISTORYSOCIETY. 98(2),AUG. 2001 295
MISCELLANEOUS NOTES
Acknowledgements K. Harikantha and Sridhar B. Harikantha. The
fieldwork was done with Prakash Pandit of the
IthankDr.K.C. Jayaramforconfirmingthe Dr. A.V. Baliga College for Science and Arts;
identification, and Prof. Madhav Gadgil for help special thanks are due to him for his active
and encouragement. I thank the Karnataka Forest participation.
Departmentandthe MinistryofEnvironmentand
ANURADHABHAT
Forests, Govt, ofIndia for financial assistance to April, 1999
facilitate the fieldwork. Centrefor Ecological Sciences,
This work would not have been possible Indian Institute ofScience,
without the assistance ofSridharPatgar, Vamana Bangalore 560012, Karnataka, India
References
Day, F. (1889): The Fauna of British India, Jayaram,K.C.(1955):ThePalearcticelementinthefish
including Ceylon and Burma. Fishes 1: xiii+548 faunaofpeninsularIndia.Bull.Natl. Inst.Sci. India
pp. 7:260-265.
Jayaram, K.C. (1952): Taxonomic notes on the fish Jayaram,K.C.(1981):FreshwaterfishesofIndia,Pakistan,
PseudobagruschryseusDay, 1865.Ann.Mag.Nat. Bangladesh,Burma,andSri Lanka. HandBookof
Hist. 12(5):980-983. ZSI,Calcutta.No.2,XI 1 +475pp.
25. RANGE EXTENSION OF MYSTUSBLEEKERI(DAY) TO THE FRESH WATERS OF
TAMIL NADU ANDNOTES ON ITS CONGENERS IN TAMIL NADU AND SRI LANKA
Day(1875-78)namedthespecimensfrom gill-rakers on the lower arm, 9-11 vs. 22-27
RiverHooghly,CalcuttaMacronesbleekeri(now (Sharma and Dutt 1983).
Mystus bleekeri) which Bleeker in 1853 had The distribution ofbleekeri is stated to be
identified as belonging to the species keletius north India, with Mahanadi as its southern limit
(Valenciennes, 1839: type locality - (Menon 1999;Jayaram 1999).However, Sharma
Pondicherry). Though both the species bear and Dutt (op. cit.), reported it from peninsular
lateralstripes onthebody, they differin several India (Andhra Pradesh: Guntur). Recently, the
characters. In bleekeri the occipital process is species was reported from Neyyar river in
,
twiceaslongasbroadandreachesthebasalbone Thiruvananthapuram district, Kerala by Raju et
of dorsal; adipose dorsal base is long, al. (1999), andPonmudi, alsointhesamedistrict
commencingjustbehind lastdorsalray, itsbase (Cherian et al., in press).
being 2.4 times the rayed dorsal; maxillary This report is based on collections made
barbels are long, reaching the anal fin, whereas duringpaddyfieldecosystemstudiesbythethird
in the latter, the occipital process is narrow, author. Ten specimens ranging in length from
being 3 times as long as broad at the base and 59 to 122 mm SL were collected during May-
does notreachthebasalbone ofdorsal; adipose October 1999, from Singapemmal Koil paddy
dorsalbase is shorter being 1.1 times the rayed field in Chengleput district. This extends its
dorsal base, with wide interdorsal space; distributional range to Tamil Nadu.
maxillary barbels are shorter, reaching only the Jayaram (op. cit.) listed 19 species of
middle ofpelvic fin(Day, op. cit. Misra 1976). Mystus from the Indian subcontinent, ofwhich,
;
M. bleekeri (Fig. 1) also differs fromthe widely with the recent inclusion of microphthalmus
distributed striped catfish vittatus (Bloch 1797) (Day) from Manipur, 14 species are represented
by its longer adipose dorsal and less number of in Indian territory. With the exception of this
296 JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 98(2), AUG. 2001