A new sisorid catfish of the genus Myersglanis Hora & Silas 1951, from Manipur, India

6 Pages·1999·3 MB·

by  Waikhom Vishwanath

A NEW SISORID CATFISH OF THE GENUS MYERSGLANISHORA & SILAS
1951, FROM MANIPUR, INDIA1
WaikhomVishwanathandLaishramKosygin2
(With oneplate andone text-figure)
Key words: Catfish, Sisoridae, Myersglanisjayarami sp. nov., Manipur
A new freshwater sisorid catfish, Myersglanisjayarami is described here based on eight
specimens collected from Laniye river (Chindwin drainage) of Manipur, India. It is
characterised by a band oftransverse teeth in the upperjaw which is slightly indented in
themiddleanteriorly,andconicalandpointedteethinthejaws. Thespeciesisalsodistinct
inhaving 10branchedpectoralrays,5 branchedanalrays, 15-16branchedcaudalraysand
an adiposedorsalfinconfluentwithcaudal fin. Akeytothespeciesof genusMyersglanis
is also given.
Introduction Myersglanis during an investigation of hill
stream fishes in Ukhrul dist., Manipur, India.
Day (1869) described Exostoma blythi TheydifferfromM. blythiinmanyrespects. The
withoutmentioning itstype locality. Thespecies fish is described here as a new species.
was assigned to the genus Glyptosternum The specimens were fixed and preserved
McClellandbyHora(1923)andtoEuchiloglanis in 10% formalin. Measurements and counts
ReganbyNorman(1925).HoraandSilas(1951) followedJayaram(1981).Allmeasurementswere
proposed a new genus Myersglanis to made with a calliperto the nearest 0.1 mm. The
accommodate Day’s species as ithadcharacters type specimens of the new species have been
distinct from species of other glyptostemoid depositedintheManipurUniversityMuseumof
genera. Myersglanisis distinctinhaving conical Fishes (MUMF).
andpointed teeth onboth thejaws, a transverse Abbreviations: ASB, Asiatic Society of
band of teeth in the upper jaw which is not Bengal; ZSI, Zoological Survey of India,
producedbackwardsatthesides,andcontinuous Calcutta; SL, standard length; HL, head length;
lower labial fold. Other characters include a SD, standard deviation; M, mean.
dorso-ventrally flattened body with laterally
compressed caudal peduncle, gill openings Myersglanisjayarami sp. nov.
mm
restrictedtothedorsalsurface,weakdorsalspine, Material examined: Holotype 82.0
:
MUMF
lunate caudal fin, first ray of paired fins SL, Regn. No. 2138, Locality: Laniye
corrugatedventrallyinpinnatefoldsforadhesive river at Jessami, Manipur, India (94° 32' E, 25°
purpose and absence of thoracic adhesive 38' N), Coll. L. Kosygin, 15.viii.1994.
mm
apparatus. Thispeculiarmonotypicgenusoccurs Paratypes 7exs.,54.0-75.0 SL,Regn.
:
MUMF
only in Nepal (Misra, 1976; Jayaram, 1979; No. 2105, 2139-2144, collection data
TalwarandJhingran, 1991). Recently,oneof us same as holotype.
(L. Kosygin) collected eight specimens of Diagnosis: Myersglanisjayarami sp. nov.
is easily distinguished from its only congener
'AcceptedAugust1997 M. blythi in having less branched pectoral rays
departmentof LifeSciences, (10 against 16-17); more branched caudal rays
ManipurUniversity
Canchipur795003,Manipur. (15-16 against 13); anal fin origin equidistant
JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 96(2), AUG. 1999 291
NEWDESCRIPTIONS
Table1
MORPHOMETRICDATAOFMYERSGLANISJAYARAMI
SP.NOV.HOLOTYPE(MUMF2138)AND
7PARATYPES(MUMF2105,2139-2144)
Holotype Holotype&Paratypes
Range Mean SD
StandardLength(mm) 82.0 54.5-82.0 - -
%
In SL:
Headlength 20.1 20.1-23.8 22.1 1.2
Bodydepth 15.2 12.9-17.7 163 1.6
Headheightatocciput 11.6 11.2-14.7 13.1 1.2
Headheightatorbit 9.7 9.5-12.0 10.5 0.6
Headwidth 20.1 19.2-22.0 20.9 0.9
Snoutlength 9.7 9.7-11.1 10.4 0.3
Eyediameter 1.8 1.8-2.4 2.1 0.2
Inter-orbitalspace 5.5 5.2-73 6.2 0.7
Intemasalspace 4.3 4.3-53 4.8 0.4
Mouthwidth 7.9 7.9-9.0 8.5 0.4
Caudalpedunclelength 20.7 19.0-21.8 20.3 0.9
Caudalpeduncleheight 12.8 11.5-14.0 12.8 0.9
Dorsalfinheight 15.2 14.3-16.7 15.6 0.7
Adiposedorsalfin
C C' length 31.7 27.2-34.3 31.4 2.1
Adiposedorsalfin
Fig. 3:Natureofteethbandalongwithshapeoftooth: height 2.4 1.5-3.0 2.4 0.5
Myersglanisjayarami (A, A'), Pectoralfinlength 17.7 16.8-19.3 18.3 0.8
Exostoma vinciguerrae (B, B') Pelvicfinlength 15.8 15.3-16.7 16.0 0.6
Analfinheight 12.8 12.2-14.7 13.6 0.9
Euchiloglanis sinensis (C, C') UpperCaudalfinlobe
length 17.1 16.0-17.5 16.8 0.6
frompelvicfinoriginandcaudalfinbase(against LowerCaudalfinlobe
nearercaudalbase)andalsoinhavinganadipose length 18.3 17.2-19.3 18.1 0.8
dorsal fin which is confluent with caudal fin. Distancebetween
snouttip&:
Description Dorsalfininsertion 39.0 37.4-42.1 39.8 1.6
Pectoralfininsertion 15.2 14.5-17.2 15.7 0.9
The lateral view of the fish is shown in Pelvicfininsertion 44.5 44.5-47.4 46.4 1.0
Analfininsertion 73.2 73.2-75.2 74.0 0.7
Plate 1, Fig. 1. Morphometric data ofholotype Vent 67.1 67.1-69.5 68.2 0.9
and 7 paratypes are given in Table 1. Head and Posteriormarginof -
body depressed. Ventral surface flattened from lowerlabialfold 7.8 7.8-10.0 9.3 0.8
snout to vent, caudal peduncle laterally Inter-dorsalspace 19.3 18.4-25.3 20.9 2.3
compressed, its depth 59.4 - 69.2% its length Veonritgrianlsfintoanaltin 26.4 25.7-27.5 26.8 »0.9
(M= 63.1; SD=3.4). Head broad, width 88.9- Analfinorigintocaudal
100.0 % HL (M= 94.7; SD= 4.1), height at base 27.8 25.2-27.5 26.5 0.6
occiput48.1-68.3%HL (M=59.2; SD=4.9). Eye Maxillarybarbellength 16.5 16.3-19.3 17.6 1.1
Nasalbarbellength 8.5 8.4-10.5 9.1 0.7
verysmall,subcutaneous,notvisiblefromventral
Outermandibular
surface, almost in the middle of HL, diameter barbellength 6.7 6.1-8.8 7.2 0.8
8.4 - 10% HL (M=9.3; SD=0.5). Snout obtuse, Innermandibularbarbel
length 44.4-49.7 % HL (M= 47.3; SD= 1.9). length 2.4 23-3.5 2.8 0.4
292 JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 96(2) AUG. 1999
NEW DESCRIPTIONS
Vishwanath, Waikhom etal.: Myersglanisjayarami PLATE 1
Fig. 1: LateralviewofMyersglanisjayaramisp. nov.
mm
(Holotype, 82.0 Standardlength)
Fig. 2: VentralviewofMyersglanisjayarami
JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, 96(2), AUG. 1999 293

NEWDESCRIPTIONS
Mouthinferior,transverse, surroundedbyfleshy Distribution: Lainye river at Jessami,
lips, width 34-41% HL (M=38.5; SD= 2.0). Manipur (Chindwin drainage), India.
Lower labial fold continuous. Teeth conical, Etymology: The new species is named
pointedanddirectedbackwardsinbothjaws.The after Dr. K.C. Jayaram who encouraged us in
band ofteeth in the upperjaw slightly indented this work and provided relevant literature.
in the middle and not produced backwards at
the sides (a comparison of shape of teeth and Discussion
teeth bands ofMyersglanisjayarami and other
Glyptosternoid fishes is shown in Fig 3). Hora and Silas (1951) classified
However, the bands are not separated into two Glyptosternoidfishesbasedonthenatureofteeth
as in Exostoma Blyth. Teeth band in lowerjaw and form of teeth bands in the jaws. They
is divided in the centre andpointedtowards the consideredthenatureofthefoldoflowerlipalso
sides. Plate edentulous. Gill openings dorso- as a generic character apart from dentition. The
lateral, extending only to the opposite base of new species has all the characteristic features of
the pectoral spine. Barbels 4 pairs, maxillary the genus Myersglanis i.e., the presence of(i)
,
barbels with broad base and its ventral surface all conical andpointedteeth in bothjaws, (ii) a
provided with pinnate folds. It extends to one- continuous teethband inthe upperjaw, and(iii)
third of the length ofpectoral fin base. Nasal a continuous lower labial fold.
barbels exceed posterior margin oforbit, outer The species described here is similar to
mandibular barbels just reaching pectoral fin Euchiloglanis Regan, in the shape ofteeth and
origin.Innermandibularbarbelveryshort. Chest nature of teeth bands. However, it differs in
transversely striated on the sides, gradually having a continuous lower labial fold compared
becoming posteriorly directed skin folds on the to the widely interrupted fold ofthe latter. Hora
extremities (Plate 1, Fig. 2). and Silas (op. cit.) considered this a major
Rayed dorsal without strong spine. It has character in distinguishing the two genera. The
one simple and 6 branched rays. Its origin lies new species has a continuous lower labial fold
nearer to snouttip than to caudal base. Adipose as in Exostoma Blyth. But Exostoma is distinct
dorsal fin low, long and confluent with caudal in having oar-shaped teeth and two clearly
fin. Paired fins are broad, rounded, their inner separated upper teeth bands.
halfverticalandouterhalfhorizontalinposition. With this report, the genus Myersglanis
Thefirstrayofpairedfinsflattenedandventrally is no more monotypic and its range of
corrugatedinpinnatefolds.Pectoralfinwithone distribution extends up to Manipur, India
simpleand 10branchedrays.Pelvicfinwithone (Chindwin drainage).
simple and 5 branchedrays. Pectoral andpelvic Comparative materials: Myersglanis
finsareseparatedbyaconsiderabledistance.Anal blythi: ASB Cat. F 599 in ZSI, 2 ex., 55.0-57.5
mm
fin with one simple and 5 branched rays. Its SL, Pharping, Nepal, Coll. F. Day, no date.
originliesequidistantfrompelvicfinoriginand Euchiloglaniskamengensis:ZSIF2106/2, 2ex.,
caudal fin base. Caudal fin lunate, lower lobe Paratype Norgum river, Kalaktang Kameng
,
slightly longer than the upper with 15-16 Frontier Division, NEFA, Coll. K.C. Jayaram,
branchedrays. Laterallinedistinct. Skinsoftand 22.iii.1961. Exostomavinciguerraem-mZSI¥6661/
smooth. 1, ZSI F6671/1, 2 exs, 34.0-37.5 SL, Pazi,
Colour of live specimen: Yellowish grey Moughong, N. Shan States, Myanmar. Coll. J.
MUMF
to dingy olive brown with pale white ventral Coggin Brown, no date, 2356, 4 ex.,
mm
surface. Head, dorsal streak and lateral line 50.6-76.7 SL,Adaikistream,Manipur,Coll.
darker; caudal fin dusky. M.G. Sharma, no date; E. berdmorei, ASB cat
JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 96(2), AUG. 1999 295
NEWDESCRIPTIONS
mm
597, type, 64 SL., Tenasserim, Myanmar, Pectoral fin with 10 branched rays, Caudal fin with
Coll. Maj. Berdmore, no date. E. stuarti, 15-16 branched rays M.jayarami
mm
Holotype,44 SL,ZSIF9742/1 Putaoplains, :
, Acknowledgements
Tanja, Tibetan Frontier, Myanmar, Coll.
Dr. Murray Stuart, no date. We thank Mr. T.K.Sen, Head, Freshwater
FishSection,Dr.Karmarkar,ZoologicalAsst,and
Key to speciesof genus Miss Lina Sarkar, ProjectFellow, Z.S.I., Calcutta
Myersglanis Hora & Silas for their valuable help during thejunior author’s
study at the IndianMuseum, and the Ministry of
Pectoralfinwith 16-17branchedrays;Caudalfinwith Environment & Forests, New Delhi (ProjectNo.
13 branched rays Myersglanis blythi 1141/IFD/97) for financial assistance.
References
Day, F. (1869): Remarks on the fishes ofthe Calcutta India, No. 14: 1-62.
Museum.Proc.Zool. Soc.London., 511-527. Jayaram, K.C. (1981): The freshwater fishes ofIndia,
Hora, S.L. (1923): Notes on the fishes ofthe Indian Pakistan, Bangladesh, Burma and Sri Lanka - a
Museum5.-onthecompositegenusGlyptosternum handbook.ZoologicalSurveyofIndia,p.475.
McClelland.Rec. Ind. 25: 1-44. Misra,K.S.(1976):TheFaunaofIndiaandtheadjacent
Hora, S.L. & E.G. Silas (1951): Notes on the fishes of countries, Pisces 3. Zoological Survey ofIndia,
IndianMuseum,47.RevisionoftheGlyptostemoid p. 367.
fishesofthefamilySisoridae,withdescriptionof Norman,J.R.(1925):TwonewfishesfromTonkin.Ann.
newgenusandspecies.Rec. Ind. 49:5-29. Mag. Nat. Hist. 15(9): 570.
Jayaram,K.C.(1979):Aidtotheidentificationofthesisorid Talwar,P.K.&Jhingran,A.G.(1991):FreshwaterFishes
fishes ofIndia, Burma, Sri Lanka, Pakistan and ofIndiaandadjacentcountries,2.Oxford&IBH,
Bangladesh, 3, Sisoridae. Occ. Pap. Zool. Surv. NewDelhipp.543-1158.
296 JOURNAL, BOMBAYNATURAL HISTORYSOCIETY, 96(2) AUG. 1999