— 2011.TheJournalofArachnology39:337-344 Cytogenetical characterization ofsix orb-weaver species and review ofcytogenetical data for Araneidae DouglasAraujo',VivianeF.Mattos^AndreMarsolaGiroti’^MarciaG.Kraeski-,LeonardoS.Carvalho^andAntonioD. Brescovit^: 'Universidade Estadualde Mato Grosso do Sul-UEMS, Unidade Universitariade Ivinhema, Mato Grossodo Sul, Brazil. E-mail: [email protected]; -Universidade Estadual de Mato Grossodo Sul-UEMS, Unidade Universitariade Mundo Novo, Mato Grosso do Sul, Brazil; ^Universidade Estadual Paulista-UNESP, Institute de Biociencias,DepartamentodeBiologia,RioClaro,SaoPaulo,Brazil;‘‘UniversidadeFederaldoPiaui,CampusAmilcar FerreiraSobral, Piaui, Brazil; ^LaboratoriodeArtropodes, Institute Butantan, Sao Paulo, Brazil Abstract. ThefamilyAraneidaeisthethirdlargestamongspidersandthethirdmoststudiedfromacytogeneticalpointof view.Inspiteofthis,only2%ofallaraneidshavebeenkaryotyped.Themajorityofaraneidsanalyzedpossess2n = 24 chromosomesinmales;however,thestudyofadditionalspeciescouldrevealunusualkaryotypecharacteristics.Thus,the aimofthisworkistoanalyzechromosomally,forthefirsttime,sixspeciesbelongingtothreearaneidgenerafromBrazil. The specimensofAlpaida leucogramnui (White 1841), Alpaida tnmeata(Keyserling 1865), Alpaida veniliae (Keyserling 1865),Parawixiakochi(Taezanowski 1873),ParawLxkivelutina(Taezanowski 1878)and Wagnerianasp.werecollectedin Barque Nacional de IlhaGrande and in the municipality ofRio Claro. The gonads were treated with colchicine and hypotonicsolutionbeforefixationwithCarnoyIsolution.Theresultswere2nS=24(IIII+XiXt)inA.leucogramnuiand P. velutina,and2nS = 22(10n+XiX2)inA. truncata,A. veniliae,P. kochiand Wagnerianasp.Whenthechromosomal morphologieswereestablished, weobserved telocentricchromosomes in allspecimens saveone femalespecimen ofP. velutina.Theunivalentsexchromosomeswereeasilyrecognizedondiplotenes.Theunpairedmetacentricelementfoundin onefemalespecimenofP.velutinawith2n=25probablyarisesbycentricfusion/fission.Araneidaeisamegadiversefamily composedof—3000speciesdistributedmainlyinthetropics;thustheanalysisofmorespeciesmayprovidenewinsights aboutorb-weaverchromosomeevolution. Keywords: Sexchromosomesystem,meiosis,mitosis,chromosome,spider Despite the fact that the spider family Araneidae Clerck 2011).Thegenus Wagnerianacomprises41 speciesdistributed 1757isthethirdlargest,comprising3006speciesin 168genera mainly in Central and South America (Levi 1991; Platnick (Platnick2011),only65speciesfrom20generahaveeverbeen 2011). cytogenetically characterized (approximately 2% ofthe total Cytogeneticalstudiesofspidersarescarce,thushypotheses diversity). Although relatively few araneid species have been regardingchromosomalevolutionaredifficulttoformulateor studied,theyrepresentthethirdmoststudiedfamilyfromthe test.Theaimofthisstudyistocharacterizeforthefirsttime cytogenetical point ofview. However, there are many gaps thespeciesA. leucogramma,A. truncata,A. veniliae,P. kochi, remainingin ourknowledge ofthisdiverse group. Ofthe65 P. velutina, and Wagneriana sp. in relation to the diploid speciesstudied,atleast50showadiploidcomplementof2nS number,chromosomalmorphology, andtypeofsexchromo- = 24, with 22 autosomal elements and an X1X2 sex some system. Our study represents the first cytogenetical chromosome system. The remaining species’ diploid number characterizationofNeotropical araneidspecies. vsaerxiecshfrroommo2s«oc?me=s1y3sttoem2niSs =th4e9.mMoosrteocvoerm,mowhnilewitthheinX1tXhe2 METHODS family,thetypeXoccurredwithasmallerfrequency,andthe Spiders were collected in the Parque Nacional de Ilha X1X2X3andXYtypeswereeachobservedinonlyonespecies. Grande,Parana,Brazil,andinthemunicipalityofRioClaro, Thechromosomalmorphologyformostspeciesisclassifiedas SaoPaulo,Brazil(Table2),between2008and2009.Afterthe acro/telocentric(summarizedinTable 1). gonads were dissected, the specimens were deposited in the The araneid genera Alpaida O. Pickard-Cambridge 1889, arachnological collection of the Instituto Butantan (IBSP, Parawixia F.O. Pickard-Cambridge 1904, and Wagneriana curator1. Knysak)in thestateofSao Paulo, Brazil. F.O. Pickard-Cambridge 1904, represent genera that have Chromosomal preparations and standard staining were never been cytogenetically evaluated. The genus Alpaida is performedaccordingtoAraujoetal. (2008). Themitoticand limited to Central and South America and comprises 140 meiotic cells were photographed using a digital-imaging species (Platnick 2011). Alpaida leucogramma (White 1841) capture system coupled to a light microscope, and the and Alpaida veniliae (Keyserling 1865) are distributed from chromosomal morphology wasclassified according to Levan Panama to Argentina (Platnick 2011). Alpaida truncata etal. (1964). (Keyserling 1865) is found from Mexico to Argentina (Levi RESULTS 1988;Platnick2011).ThegenusParawixiaincludes31 species, whichoccuralmostexclusivelyinCentralandSouthAmerica. Alpaida. Theanalysesofspermatogonial metaphasesand Parawixiakochi(Taezanowski 1873) is found fromTrinidad spermatocytes I of A. leucogramma showed 2n^ = 24 = rtoecoBrrdaezdilfraonmdCPoalroamwbiixaiatoveAlrugtiennatin(aTa(eLzeavniow1s9k9i2; 1P8l7a8t)niciks 2le2n-1g-tXh1X(2Fitge.lolcAe)ntraicndch1r1omaoustoomseosmatlhabtivdaelcernetasseplgursadtuawlolyseixn 337 THEJOURNALOFARACHNOLOGY s:§ ° Onon orOoonoONoOoOOon II 2 oS, Si Si Si •HOC..’38o: oGO"N £o3Cs:S£§SoC£oSs a -ao^o^^ .QScN^ OS__ ^_•SOSCNXoGCsc•G^—a«^•OcaN^HSQ^N^^oao<<aUs QQU ^mO'c33"iic;5dQ3^j^DS^QS^SS e c c _____ c c c 'Da.'aD.'Sa. £C£C -noS^"O §- 'I "&3H"eGu"fIe ^ 3 c s c << << <H o_o XX XX XX o"o XX X X XX <H XX'^ ot)Nr-i 0. p XX>X< XxXxXxXxXxXxXxXxXx XXXXXXXX XXXXXXXXXXXXXX XX XXXX XXXXXXXXXXXXXX g § §S -o c jj > 1 . a -23 ?s s?^I^s:^| '"'gGd33.-.2t^gys. ^I§g^3j"^§!^"I^I3 .I§L2.^^-IXSS.#.2i13 II X•S^2'X-5S2bX-SS2i' 1) (U ^oor- ^ia3IoSSn X•GS^^:-X2OSP3^ 3-XISS'-^XiS''233cG3ss5ua-"ur^^XGS-'u^rXaS- aSSbsooso COGi.s02goo02«"^G2s^^KSa^g3^.r.SK=-a8a8=j• X-8^?CSX-28I^CS;X-I82-OSQ.D-&S, S -s"S|-5••CRaI£'S®-Si)J'S^.SOa§aa®|-"=nc-2a?aSo3l X.IS5au§XX•2aI§XX-2aII X—'SSaGS''o.C"®2aa-auf\^UMC'ioag®/S5.oj^^t-Q§2Oj_^jaj-a^UJ-^O^"QN2sJ-2jUS^OC^^aN>lU^aas(soo^cD ARAUJOETAL.—CYTOGENETICCHARACTERIZATIONOFORB-WEAVERS 339 340 THEJOURNALOFARACHNOLOGY 1895 Simon Araneidae : ARAUJOETAL.—CYTOGENETICCHARACTERIZATIONOFORB-WEAVERS 341 — Table 2. Listofspeciescytogeneticallyanalyzedinthepresentstudy,withthenumberofspecimens(malesandfemales)studied,numberof cellsanalyzed(Cells),collectinglocationanddepositnumberofthespecimensinthearachnologicalcollectionoftheInstitutoButantan(IBSP). ThenumberofspecimenofP. velutinawith2n = 25isinboldletters. Species d $ Cells Collectionsite IBSP Alpaidaleucogramma 1 30 CampusUNESP(22°23'33.97"S, 53028 47°32'37.39"W),RioClaro,SaoPaulo, Brazil Alpaidatruncata 2 - 107 SaoFranciscoIsland(24°00'32.40"S, 153928, 151186 54°09'52.18"W),Parana,Brazil Alpaidaveniliae 1 1 27 Xambrelakemargins(23°52'48.64"S, 145318, 145319 54°0T2.25''W),Altonia,Parana,Brazil Parawixiakochi 1 - 62 SaoFranciscoIsland(24°00'32.40"S, 123695 54°09'52.18"W),Parana,Brazil Parawixiavelutina 3 3 348(224-2/7=24 SaoFranciscoIsland(24°00'32.40''S, 123717, 154838, 154847, and26; 124-2n=25) 54°09'52.!8"W),Parana,Brazil 154844, 154842, 151176 Wagnerianasp. I 287 SaoFranciscoIsland(24°00'32.40"S, 152927 54°09'52.18"W),Parana,Brazil univalents (llII+XiXo) (Fig. 2A). The sex chromosomes Xj bivalents, respectively (Fig.2D, E). Both species have two and X2 are the smallest ofthe complement (Figs. lA, 2A). sexualunivalentsthatalwaysappearsidebysideandcorrespond Diplotenes ofA. truncata (Fig. 2B) andA. veniliae(Fig. 2C) to the Xi and X2 chromosomes (Fig. 2D, E). Therefore, the asnhdowetdwomeisoetxiucalfournmiuvlaaleentcsomp(rIiOsIiIn+gX11X02)auftoorsobmoatlhbisvpaelceinetss, dmiepilootiidcnfuomrbmeulraofof2«Pc.?=ko2c2h.iIinsPI.OvIeIl+utXi1nXa2t,hecomrerieostpiocnfdoirnmgultaoias XainiudtioacsanotdimneXgs2aansdedixptlhuoeniidXva1nlXeun2mtbsseexralcwhoafryos2mnoaSspop=meeas2r.2,tIoncobAme.ptosrisudenedc-abyto-afsti2hd0ee co1oo1g1mo1p+nlieXaml1eXnm2te,tiawnpadhisacascteoisnngfoiafrmdteiwpdolobifydemctaohlemepsplroeefmseePnn.ctevoeflouf2tni2nd/at?=(F=2i4g..2T6IhBi)is.n (Fig. 2B). In ail Alpaida studied, the sex chromosomes are Mitotic metaphases of one female specimen of P. velutina positive heteropycnotic in a number of diplotene nuclei showedanastonishingcharacteristic;thediploidnumberis2«9 (Fig.2A-C). The majority of autosomal bivalents showed =25,withalargeunpairedmetacentricchromosome(Fig. 1C), only one terminal chiasm, but bivalents with an interstitial contrastingwith the telocentric elements ofthe karyotype. In chiasmalsooccurred(Fig. 2A-C).Afemalepachytenecellof both analyzed Parawixia species, the autosomal bivalents A. veniliae revealed 12 chromosomal bivalents (Fig. 3A), showed only one interstitial or terminal chiasm. Differential indicating the occurrence of 2«9 = 24, comprising 20 pycnosis was not observed in any chromosome of the cauhtroosmoomseosmaalndmotrhpehXojloXg1yX2wXas2 sneoxtceshtraobmliosshoedmeinsAy.stetmr.uncTahtea cmeotmapplheamseentIIinnuclPeaursawwiaxsiafosupnedcieisn P(.Fikgo.ch2iD,,shEo)w.inOgnl«y=on1e0 andA. venilia—e,duetothelackofmitoticormetaphaseIIcells. autosomesand—nosexchromosomes(Fig. 3B). Pamwixia. The observation ofspermatogonial diplotenes Wagnenana. The analyses of male diplotene cells in of P. kochi and P. velutina showed 10 and 11 autosomal Wagneriana sp. revealed 10 autosomal bivalents and two it; "a "f 1 1% l! A 1 2 3 4 5 6 '7 8 9 10 11 12 j 1 ' r11 M W if !I If II 11 B 2 3 4 5 6 7 8 9 10 11 12 13 i M m m M II SI ii ii Bi c 1 2 3 4 5 6 7 8 9 10 11 12 13 Figures lA-C.—Karyotypes ofaraneid species. A. Alpaida leucogramma, with 2nd = 24 =22+XiX2 telocentric elements; B. Parawixia tveelluotciennat,ri2chs9a=nd26on=e2u2np+aXir1Xed1Xme2Xta2cetneltorciecntcrhicrocmhorsoommoes,omperso;baCb.lyParreaswuiltxioafvaelcuetnitnrai,chfeutseiroonz.ygSoctaelesp=ec1i0mepnm,.2n9=25=2I+X1X1X2X2,with24 342 THEJOURNALOFARACHNOLOGY / ~ : V n ^30 A Lc 1 V i W ^ D BW,aFgCin.geurArileapsnaai2dAsa-p.Ft,.niI—nOcIMaIat+alXea1Xndid2p.lAAolrtperanoiewdssaofivenandriialcinaaeteie,dirsnetpseeprcesitceitsti.ivaeAll.yc,AhlilpaOasIimIda+aXalineXduic.aorgDrr.oawmPmhaaer,aadw1si1xiainaudtikocoasctloeimia,tlerIbmOiiIvnIaa+lleXnc1tXhsi2pa.lsuEms.a.tPwSaocmawsleiexx=cihar1vo0epmlmou.tsionam,esII(1III+IXI+1XX12X.2F).; sneuxmubalerunoifva2lnednt=s (2I2.OITIh+eX1aXu2t)os(Foimga.l2Fb)i,valseungtgsesptriensgenateddipolnoliyd a(2nnd A=. 2l2e)ucaongdraPm.mave{l2unti=na24{)2,na=s we2l4l)acsoubledtwbeeenusP.efuklochais one terminal or interstitial chiasma. The sex chromosomes a cytotaxonomical character, which, together with genital werepositiveheteropycnoticinrelationtotheautosomesand characteristics, can be used to identify these closely related, always appeared closely associated (Fig. 2F). It was not sympatricspecies. possibleto identifythechromosomal morphologydue to the The 2n^ = 22 diploid number has now been observedfor lackofmitoticmetaphasesormetaphase II. the first time in Araneidae (see Table 1) for the species A. DISCUSSION truncata, A. veniliae, P. kochi and Wagneriana sp. It is interesting to note that Levi (1992), in a taxonomic review, Theacquisitionandanalysisofcytogeneticdatamayshow indicatedthatthegeneraParawixia,Alpaida,and Wagneriana more difficulties than the acquisition of morphological or shared (together with Acanthepeira Marx 1883, Wixia O. molecular data; i.e., the specimens must be kept alive until Pickard-Cambridge 1882, Eriophora Simon 1864, Verrucosa dissection and must present cells in division (Araujo et al. McCook 1888 and others) some external morphological 2005). However, molecular sequencing, despite becoming putative synapomorphies (see Levi 1992 for details). The moreaccessible, is notavailable formany researchers out of presence ofspecies with 2n = 22 exclusively in these genera the majorresearch centers. Thus, chromosomal data can be amongaraneidscould beconsidered furtherevidenceoftheir used 1)asacomplementtomolecular/morphologicaldata,2) close relationship. Unfortunately, there is no cytogenetical when molecular data are not available, or 3) when data on other closely related genera such as Acanthepeira, morphologicalcharacteristicsarenoteffectiveforidentifying Wixia, Eriophora, Verrucosa and Edricus O. Pickard-Cam- species (i.e., cryptic species). Moreover, the chromosome bridge 1890. numberhasalreadybeenusedintaxonomicaldescriptionsof Ofthethreearaneidgenerastudiedhere, onlyAlpaidawas spider species (see Maddison 1996). The differences in male included in the phylogenetic hypothesis of Scharff & diploid number between A. truncata, A. veniliae {2n = 22), Coddington (1997), whose results do not corroborate the hypothesis of Levi (1992), since the genera Acanthepeira, Eriophora and Verrucosa appeared far from Alpaida, that 1 * j a1r8i8s4e,swEintahcinrocsloadmea63M,elwlhoi-cLheiatlasooi1n9c3l2u,desEuBsetratlraanSaiKmeoynser1l8i9n5,g WixiaandAcacesiaSimon 1895(Scharff&Coddington1997). » Of these genera, the only one that has a description of * Jt cytogenetical data is Eustala, which possesses the most common chromosome number in araneids, 2nS = 24 (see A B Table 1). Thus, a more extensive cytogenetical study of Araneidaerepresentativesisnecessaryinordertounderstand A.FAilgpuariedsa3vAen-iBl.iae-Efaermallyeapnadchlyatteenmeewiiotthic12stbaigveasleinntsa,rianndeiicdatsipnigde2r«s.9 cthhercohmroosmoomseomnaulmbeevorlu{t2inon=p2r2o)ceisnsPtahratawriexsiulateadndinAtlhpeaisdmaa.ller = 24. B. ParawixiakocliimalemetaphaseII,/! = 10chromosomes. Araneids, in general, have exclusively acro/telocentric Scale = 10pm. chromosomes (Table 1). Exceptions are 1) two Argiope ARAUJOETAL.—CYTOGENETICCHARACTERIZATIONOFORB-WEAVERS 343 ji Audouin 1826 specieswith 2nS = 24biarmed orholocentric alsoveryfrequentintheTheridiidaeSundeval 1833b,another i chromosomes(Amalin1988;Amalinetal. 1992;Carandang& araneoidfamily(Araujoetal. 2010). Wealsoshowthateven Barrion 1994a) and 2) one Larinioides Caporiacco 1934 and withinagenus(i.e.,ParawixiaandAlpaida),somespeciesare three Neoscona Simon 1864 species that have karyotypes 2nS = 24, while others are 2nS = 22, suggesting that the 1;( composed of 2nS == 14 chromosomes, with 10 metacentric rearrangements involved in the conversion from 24 to 22 !> elements(Hackman 1948; Suzuki 1951b;Amalinetal. 1993). chromosomes or vice versa are relatively common among AccordingtoSuzuki(1951b),thesecondcaseprobablywasa araneoidspiders. '^ skuafrfyeorteydpceenwtirtihc2funsSio=ns2t4oafcoror/mtealokcaenrtyroitcypcehrwoimtohsIonmSes=th1a4t, orbT-hwuesa,vethrisssftorudythperefsiresnttsticmyet.ogTenheeticraelsuldtastaweorfeNesoltirghotpliycailn with 10 metacentrics originated by the fusions of 20 aero/ disagreementwiththoserecordedforOldWorldspecies,and I telocentricelementsand4non-fusionedacro/telocentrics. furtherstudiesarerequiredtoevaluatewhethertheobserved In the Parawixia velutina specimen with 2/j? = 25, the patternpersistsforotherNeotropical species. Thecytogenet- I metacentricelement probably arose through a Robertsonian ical characterization ofrepresentatives ofthe genera closely fusion (centric fusion), wherethecentromeric regions oftwo related to those analyzed in the present study {Parawixia, acro/telocentric chromosomes fuse to form a single meta/ Alpaidaand Wagneriana), especially Araneines sensu Scharff submetacentric chromosome, generating a heterozygosis & Coddington (1997), and Acanthepeira, Wixia, Eriophora, condition. Frequently, chromosomal changes produce repro- VerrucosaandEdricus,assuggestedbyLevi(1992),isstrongly ductivebarriers when theycause problems duringmeiosis in recommendedastheyseemto beessential forunderstanding heterozygotes, leading to reduced fertility, owing to the chromosomeevolutioninaraneids. formation of a trivalent during meiosis and unbalanced ACKNOWLEDGMENTS segregation.However,duringmeiosissegregationbothunbal- ancedandbalancedgametescouldbeformed(Sumner2003). The authors wish to thank Cristina Anne Rheims for her InthecaseoftheheterozygotespecimenofP. velutina2«9= Englishreviewofthemanuscript.Thisresearchwassupported 25, the meiosis can proceed in two ways: 1) generate by Conselho Nacional de Desenvolvimento Cientifico e unbalancedgametesthatareeliminatedduringgametogenesis, Tecnologico (CNPq-471821/2008-0- DA; 302148/2007-8 - do not fertilize or produce unviable embryos; or 2) the ADB). Collecting permits were granted by the Instituto fusioned metacentric pairs with their two homologous Brasileiro do Meio Ambiente e dos Recursos Naturais telocentricstoformatrivalentandproperlygeneratebalanced Renovaveis - IBAMA and the Instituto Chico Mendes de gametes,somecontainingthemetacentricandotherscontain- Conservagaoda Biodiversidade(ICMBio)(#15157-1). ingthetwotelocentrics. Unfortunately,becausetheheterozy- LITERATURECITED gote individual was a female, it was not possible to observe meioticpairing. Amalin, D.M. 1988. Morphology,lifehistoryandcytologyofthree hasCebneternicrefpusoirotnedisinamvoesrtygcroomupmsonofeovroglauntiisonmasry(Wchhiatnege197a3n)d. toLhraebg-uwnPeahai,lviitpnhpeginPsehpsii.ldieprPpshiin(leAis.prpainneease:UAnrivaenresiidtaye,) cLaoussinBganaorsa,neiCdoilslmegei,n TshpiescimteynpeofofP.revealrurtainngaewmietnht,2n9a-s=pre25s,enwtlaysvoebrsiefrievdedininotnhee Amaclyitno,loDgy.Mo.f,AAr.gAi.opBearcrciitoennu&latLa.M(D.olReusecdhaal.l)19(9A2r.anMeoarep:hAroalnoegiydaaen)d. heterozygous condition in one male specimen ofthe salticid AsiaLifeSciences 1:35-44. Evarchahoyi(Peckham&Peckham 1883)thatpresents2nS= Amalin, D.M., A.A. Barrion & M. Jayoma. 1993. Comparative 25 (with one unpaired metacentric autosome), contrasting karyomorphology oftwo Neoscona species (Araneae:Araneidae). withthe2nS = 26(withoutmetacentricautosome)verifiedin PhilippineEntomologist9:1-6. otherspecimensinthesamestudy(Maddison 1982). Inmany Araujo, D., A.D. Brescovit, C.A. Rheims & D.M. Celia. 2005. cases, however, the homozygous condition rapidly reached Chromosomaldataoftwopholcids(Araneae,Haplogynae):anew fixation,withtheoriginaltelo/acrocentricelementsdisappear- diploid number and the first cytogenetical record for the New if2on«rg=tfhreo1m4prtedhveeisocpurosiplbuyeldcaitbtiyeodnHLa(arWcihkniimtoaeind1e9s(713a9)n4,8d)a,NsesSoeusezcmuoskniato(s1pb9ee5ci1tebhs)ewcaiantsdhe ArasWEupxojitrodr,leerdmDgec.el,ndauedeCgs.r.SeAJce.oyuotrfoRndhcaeehlsirmo(osfAm,roAasrnAaoe.camDehe.,nnoHluBarompegblsyeocorg3vy3vin:ata5rei9a&,1b-iS5lc9Diy6t.t.yModi.nidsCapeeel)ci.iae.Jsoou2fr0n0ta8h.le Amalinetal. (1993). ofZoologicalSystematicsandEvolutionaryResearch46:89-95. Ontheotherhand, GasteracanthahasseliiC.L. Koch 1837 Araujo, D., U.M. Maia & A.D. Brescovit. 2010. The first and Gasteracantha kuhli C.L. Koch 1837 possess 2« = 16 characterizationofthepoisonousblackwidowspiderLatrodectiis exclusivelyacro/telocentricchromosomes(Datta&Chatterjee, gr. curacaviensis from Brazil, with chromosomal review of the 1983, 1988).AccordingtoDatta&Chatterjee(1988),tandem/ familyTheridiidae(Arachnida,Araneae). Micron41:165-168. centric fusion followed by pericentric inversion from a Berry,E.H. 1906.The“accessorychromosome”inEpeira.Biological iknavroylovteydpeinwittheh o2r«icg?in=of24theacrkoa/rtyeoltocyepnetrwiicthch2rnom=os1o6m;easndi,s BolBeul-lGeotwinda1,1:B1.9N3.-210915.8.Astudyofthechromosomesduringmeiosis owing to the pericentric inversions, there are no metacentric in twenty-two species of Indian spiders. Proceedings of the cchhrroommoossoommeesnuinmbtehrerkeadruycotitoynp.e with 2n = 16, despite the CarcZaohnordloaomgnoigcs,aolmRe.SsoBc.ioef&tyArAogf.iAoB.peengBlaaurlzroi1no1an:.6(9W-a11l90c98k4..a).,Kaanryoortby-pweeavoifngthsepiedgegr In this study we found four species with 2nS = 22, (Araneae,Araneidae). PhilippineEntomologist9:443^47. suggesting that this diploid number could be more common Carandang, R.B. & A.A. Barrion. 1994b. Karyotype of egg in araneids than previously thought. This diploid number is chromosomesofanorbweavingspiderArgiopeshillongensisSinha 344 THEJOURNALOFARACHNOLOGY (Araneae:Argiopidae).Pp.32-33.InIntegratedPestManagement: Patau, K. 1948. X-segregation and heterochromasy in the spider Learning from Experience. Pest Management Council of the Araneareaumiiri.Heredity2:77-100. DatPthai,liSpp.iNn.es&,IKn.c.,ChCaotltleergjee,e.La1g9u8n3a.,CthhreoPmhoilsioppmienesn.umber and sex- PlaAtnmiecrki,caNn.I.Mu2s0e11u.mTohfeNaWtourrladl HSipsitdoerry,CaNtealwogY.orVke.rsOinolnin1e1.5a.t determiningsysteminfifty-twospeciesofspidersfromNorth-East http://research.amnh.org/entomology/spiders/catalog/index.html DatItnad,iaS..NC.hr&oKm.osChoamteterIjnefeo.rm1a98t4i.onThSeercvihcreom35o:s6o-8m.ebehaviourinthe Qinogbtsaeor,vaZt.i,onH.ofHonthge,sYp.idBeirngc,hLr.omFoesnogmxeisangby&sCi.nglJeiane.mb1r9y9o8-.ceAlnl spermatogenesis of two species of Indian araneid spiders. squashtechnique.ActaArachnologicaSinica7:39-41. DatPtear,spSe.cNt.iv&esKin.CCyhtaottleorgjyeea.nd19G8e8.neCtihcrso4m:o4s3o3-m4e3s6.andsexdetermi- Qinkgatrayoo,tyZ.p,eYp.olBiynmgo,rpHh.isHmongin,LCa.riJniiaonde&sLc.orFneuntag.-XAicatnga.Zo19o9l9o.giOcna nation in 13 araneid spiders of North-Eastern India. Genetica Sinica45:238-240. Dia7z6,:91M-.9O9.. & F.A. Saez. 1966. Karyotypes of South-American Schoarrfbf-,weNa.vi&ngJ.As.piCdoedrdinfgamtiolny. 1A9r9a7n.eAidapehylo(gAernaecthincidaan,alyAsirsanoefaet)h.e DoaAXnrXa,neRsi.edxNa..de&MteeLrm.mVoi.rniiPaanlsgiudlsioyss.Itn2es0mt0i9it.nutMetihceBruootrmaban-ntwiaepnauv3li3a:nt1gi5o3sn-p1ir5de4ev.realNseoasncXoOn-a ShaZfrormooalmo,gOiNrci.asls&a.JoBPu.rrBan.nailPkaoerfeidt8ah:.e711L-9i78n67.n.eaSntuSdoycioeftych1r2o0:m3o5s5o-m43e4s.inspiders GHoarcaslrtkoaumv/daj,icenwsI,c.aoP.Wn,(.WSOail.b1cYe9k.4re8iUn.a.aneCGrshop)ri.rdolemHoreosvr.saeodHm&ieetrnaeDsds.itVt1u.a4ds6iL:e1o1n82g02u-:an12no81v21A..-r2a210n9.9e5e.nCmyittogbeenseotni-c Shamsrtaumldaei,esmeGio.oPns.i,tsheKin.IKHn.edrisTainalinasdposinadevri&sgnyViM..LScu.hcraGosrme(owHseaorlsm.ieli1ic9d6oa0em.)p,lCeLyamtreoinlnotigaiacsnapdl. derer beriicksichtigungdergeschlechtschromosomen. Acta Zool- (Argiopidae), Tetragmitha sp. (Tetragnathidae), Oxyopes ryvesii ogicaFennica54:1-101. Pocock,andOxyopessp.(Oxyopidae).ResearchBulletin(N.S.)of Levan, A., K. 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