Isopterina, a New Subtribe of the Tribe Celeuthetini, with Notes on the Related Taxa (Coleoptera, Curculionidae)

19 Pages·2001·20.4 MB·English

by  Morimoto, K

Elytra,「okyo,29(2):265-283,Novemberl5,2001
Isopterina,aNewSubtribeoftheTribeCeleuthetini,with
NotesontheRelatedTaxa(Coleoptera,Curculionidae)
Katsura MORIMOT0
c/oEntomologicalLaboratory,FacultyofAgriculture,KyushuUniversity,
Fukuoka,812-8581Japan
and
Hiroaki KoJIMA
TheKyushuUniversityMuseum,KyushuUniversity,
Fukuoka,812-8581Japan
Abstract WeevilgeneraArrhaphogaster,Bo,・odinophihls, lsopterus, Kotoshozo,
NleasphalmusandPseudottlsti,,ahavebeenvariouslyclassifiedinthetribesPolydrusini,
Celeuthetini,PachyrhynchiniorOtiorhynchini,butarenewlycombinedtogether intothe
newsubtribeIsopterinaofthetribeCeleuthetiniinthispaper.MainfeaturesofIsopterina
aretheabsence of thetransversesulcusat thebaseof rostrum, lackof thespiculum
ventraleofthe8thsterniteinfemale,andsubdivided9thsterniteinmaleinCeleuthetini.
Newsynonymiesofgeneraandnewcombinationsofspeciesproposedinthispaperare
asfollows: IsopterusFAUST,1895 (=Kotoshozo KON0,1942,syn nov), Neasphalmtts
NAKANE, 1963 (=Borodinophihls Voss, l971,syn nov), Isopte,us kotoensis (KON0,
1942,comb nov fromKotoshozo),andNeasphalmusthai Voss,1971,comb nov from
Bo,-odinophilus).Keystothetribesandsubtribesinquestion,tothegeneraof Isopterina
andtothespeciesofNeasphalmusare given.Morphological featuresadoptedaredis-
cussedwithmany加ustrations.
WeevilgeneraArrhaphogaster,Borodinophilus,.fsopterus,Kotoshozo, Neaspha1,-
musandPseudottistlrahavebeenvariouslyclassifiedinthetribesPolydrusini,Celeu-
thetini,PachyrhynchiniorOtiorhynchiniasnotedinthefollowingcheck list,orsome
areplacedinthe“generaincertaesedis”(LoNA,1936,38;ALoNso-ZARAzAGA&LYAL,
1999). Theseconfusionmustbecausedby thedifferentvaluationofsuch featuresas
theantennalscrobes,exposedmaxillae,andshortlypedunculatepostmentum,andby
oversightofthemandibularscars.Thus,morphologicalcharactersarepreciselyexam-
inedbydissectionat first, and then important onesareselected for the taxonomyof
thesetaxa.
ThesegeneraarenewlycombinedtogetherintothenewsubtribeIsopterinainthe
Celeuthetinibased on thethreemain features:absenceofthetransversesulcus at the
baseofrostrum, lackofthespiculumventraleon the8thstemitein female,andsubdi-
266 KatsuraMoRIMoToandHiroakiKoJIMA
vided9thsterniteinmale.
TothelateDr.YoshihikoKUROSAWA,thispaperisdedicatedintokenofrespectto
thememoryofhisgreatcontributionstotheColeoptero1ogy.Heisknownasthespe_
CialistofBuprestidae,buthasinterestinawiderangeofinsectsincludingCeleuthetini
andPachyrhynchiniofCurculionidae.Thus,Celeuthetiniareselected forthjsmemor_
ia1issueasanappropriatetaxontodedicatetohim.
MorphologicalNotesontheCharactersAdopted
1. Antennalscrobes
Positionoftheantennalscrobeshavebeenadoptedasoneofthemostimportant
features for separating subfamilies in the ade1ognathous Curculionidae. Namely,
Brachyderinaeweredefinedbythecharactersthatthescrobes formingsubljnear fur_
「oWandcurvingdownwardsinfrontoftheeyes,andlateral inposition,whereasjn
Otiorhynchinaetheyaresubdorsalinpositionanddirectedtowardstheeyes,andthe
rostrumoftenhasthepterygiaexpandingoutwardsfromtheantennalsockets.
ThetribeCeleuthetinihavebeenclassifiedinthesubfamilyOtiorhynchinae,but
theantennalscrobesaredorso-1atera1tolateralinpositionandcharacteristicjnhavjng
9ene「allyopenposteriorly,triangularorbifurcate.Thepterygiaareoftenjndefjnjte
FO「example,Platyspatuslatlscapus(Fig 23)hasthescrobesbroadlyopenposteriorly
andbarebetweendorsalandventraledges;thedorsalpartisshallowlyfurrowedfrom
theantennalsockettothebaseofrostrumalongdorsolateraledge,buttheventralmar_
9inSi wavedandrunningdownwardsinfrontoftheeye,andthesubtriangularareabe_
tweenthemisbareandweaklyconvex.InPhi11c〔)ptusspp.(Figs 24,25),thescrobejs
appa「entlyく一shapedandthedorsal furrowissharpandrathershort.Inphraotesnodj_
for (Fig 26), the dorsal furrow is very short and the ventral furrow runs down
obliquelyinfrontoftheeyetotheventrolateraledgelikeBrachyderjnaeauct
Amon9thegeneraof Isopterusanditsrelatives, theantennalscrobesaremore
late「alinpositionthanthoseofmostCeleuthetiniowingtohavingbroaderinterscroba1
a「ea,buta「esimilartothoseofCoptorhynchusauct andalliesingeneralstructuresas
Wasal「eadynoticedbyGuNTHER(1943)andVoss(1971).ThetribeCeleuthetjnjhave
beenClassifiedinthesubfamilyOtiorhynchinae,buttheantennalscrobesareregarded
astheintermediatepositionbetweenthoseoftheOtiorhynchinaeandBrachyderinae
auct andthepterygiaareoftennotmarked.
2. Mouth-parts
Themouth-PartsoftheCurculionidaearegenerallydividedintotwotypesasjn
the fo11oWin9S(MORIMOT0&KOJIMA,1994).1)Phanerognathoustype:Mandibles
Withoutdeciduousprocess,oftenthinner,ventralcuttingedgelyingonorclosetothe
exteriormargin; innersurfaceoblique, almost flatorshallowly
concave; maxj11ae
Ia「9elyo「enti「elyexposed;mentumcomparativelysmallernarrowjnrelatjontothe
buccalCavity;postmentumpedunculate 2)Ade1ognathoustype:Mandjbleswjthdo_
NewSubtribeoftheCeleuthetini 267
ciduousprocessingeneral,robust,with innersurface faced totheopposite,deeply
concave,soastoreceivemaxillarypalpiandmalabetweenthem,theirventralcutting
edgelying far interiortotheoutercontour inventral aspect;mentumcomparatively
largeandcoveringornearlycoveringthebuccalcavity,soastoconcealmoreorless
completelythemaxillaeandtheirpalpi;postmentumnotoratmostshortlypeduncu-
late.
Among the tribes treate themouth-partsareof theade1ognathoustypeinthe
Celeuthetini,ElytruriniandOttistirini,whereasintheSitoninithemandiblesarepartly
ofthephanerognathoustypeinhavingtheventralcuttingedgeclosetoexteriormar9in
andalmost flat innersurface, but hasadeciduousprocess at theapex of the left
mandjble.AmongthegenerainthesubtribeIsopterina,thepostmentumisshortlype-
dunculate,andthemaxillaearepartlyexposed(Fig 7).
3. Procoxa1andmesocoxa1cavities
Thecoxaeareusuallytermedas“connateordistant”.Thesecavitiesare,however,
apparentlyinthreecharacterstatesundercloseexaminationbytakingoffthelegs:1)
thecoxaeareconnateexternallyandthecoxalcavitiesarealsoconnateinternally,2)
thecoxaeareseparatedexternally,but thecoxalcavitiesareconnateinternally,3)the
coxaeandcoxalcavitiesareentirelyseparatedbothexternallyandinternally.Among
theweevilsinquestion,theOttistiriniaretheonlytribehavingthecoxaeofthetype3,
whereasintheothertribestreatedhere,theyareofthetype1or2.
4. Tibialapex
The terminal surfaceofthetibiae isoftensubdived into thecorbel and tarsal
groovebythelongitudinalcarinaorflangeoftarsalcavity.Accordingtothetermsap-
pliedbyEMDEN(1944)andfollowedbyMoRIMoTo(1962),thecO「betSi te「med Semi-
enclosed”whenthetibialapexisdividedintothecorbelandtarsalgrooveandtheCO「一
bet jsfrjngedwitharowofsetaeexternally,andalsotermes“enclosed”whenitSi
frjngedexternallywithdoublerowofsetaealonginnerandoutermar9insofaC「eSCent
space.Thjsspaceisalsonamed“corbel”byEMDEN(1944),butnothomologousWithit
(MoRIMoT0,1962).Thus,THOMPSON(1991,1992)proposedSuch ose「iPtiVeto「mSaS
theouterbevel forthecrescentsurfacementionedabove,theinner flangefortheSemi-
enclosedcorbelsenseEMDEN,andincasewithoutthebeveland flangeitcanbede-
scrjbedassjmple.TheapexofhindtibiaehasouterbevelintheElytrurini,andflange
intheCeleuthetini.
5. Metendosternite
Themetendosterniteis fundamentallydividedintotwotypesbythep「eSenCeo「
absenceofthelateralarmsintheAde1ognatha(MoRIMoTo, l962).Thelaterala「mSa「e
present jnthesitoniniandOttistirini(Fig61),whereastheseareabsentintheCeleu-
thetjnjandElytrurini(Figs.10,52,57).TheElytruriniarecharactericticinhavin9the
peculjarmetendosternite,ofwhichthemetafurcaisdirectlyconglutinatetothemeSo-
268 KatsuraMoRIMoToandHiroakiKoJIMA
stemiteatthreepoints,oneatthemiddleofanteriormargin,andapairattheposterior
wallsofmesocoxa1bowls(Fig 57).ThisconditionissimilartothecaseofB1osyrus
Japonlcus(cf.MoRIMoTo, l962),butthemetendosterniteinthelatterisconglutinateto
themesosterniteonlyatcoxalbowls.
6. Abdomen
TheabdomenoftheCurculionoideaisofthecryptogastrantype,andthefirstand
secondstemitesareabsorbedintotheposteriorwallofcoxalcavity.Thus,thefirstven-
trite ismorphologically the thirdsternite. Amongsomegenera in thetribeCeleu-
thetini,thefemaleabdomenhasvisiblyonlytwoventrites(Fig.12).Thisconditionhas
beenexplainedasthefusionofventrites(MARSHALL,1956;Voss,1940,1958).It is
notso,but thegreatexpansionofthefirstandsecondventritesresultsthecomplete
coveringof the followingsegments.By theexaminationunder themicroscopeafter
softeningtreatmentwithKOHsolution, thethirdtofifthventritesareobservedinside
thesecondventriteas lesssclerotizedshortsegmentscontinuing fromtherespective
tergite(Figs 8,20).Bythesamemethod,theconcealedseventhsternite(=fifthven-
trite) inthefemaleofHypotactuspapi11atus,whichhasfourvisibleventrites,canbe
observedinsidethesixthsternite.
The8thseterniteinmaleisdividedintoapairofcrescentsclerites inmostcur-
culionidsaswellasthetribesinquestion,andcanbetakenoutbydissectionwith9th
stemite(Figs 42,46).The9thstemiteinmaleisasmallplatewithorwithoutmedian
incision,orpairedscleritescontinuingtoorseparatingfromtheexpandedbaseofthe
spiculumgastrale.Thesestructuresmayhaveimportantvaluefordefiningtribes.Inthe
Isopterina,9thsterniteisdividedinto3sclerites(Figs 42,44-46).The7thtergiteis
visiblyterminalinmostcurculionids.Thistergiteinmalehasapairofspiculepatches
atbase,andalmostcompletelycoversthe8thtergite.
In female,the8thsterniteistheterminal,withdrawninsidethe7th,andusually
furnishedwiththespiculumventrale.Thelengthofthespiculumventralemayhavere_
lationwiththatofovipositor. Isopterinaareuniqueinhaving8thstemiteterminaland
spiculumventraleabsent(Figs.13,21).
7. Ovipositor
TheovipositorsofCurculionoideawerewellcompared fromtheviewpointsof
bothbehavior andstructurebyHowDEN(1995). However, thesestructureshavenot
beenexaminedforthetaxonomicpurposeintherelatedhighertaxaexceptMoRIMoTo
Figs. 1-14. - 1-12.Neasphalmusokinawanus; l, female,lateral;2,maleelytra,lateral;3,rostrumand
heald,dorsal;4,rostrumandhead,lateral;5,tentorium;6,maxilla;7,labiumandmaxilla,ventral;8,
femaleabdomenrelaxedwithKOHsolution,lateral,showingtherelationoftergitesandsternites;9,
ovipositor;10,meso-andmetastema,dorsal,showingmetendostemiteandmesocoxa1bowls;11,male
venter;12,femaleventer. - 13-14. lsopterus,nac・tomerus;13,8thsternite,nospiculumventrale;
14,7thand8thtergites.
NewSubtribeoftheCeleuthetini 269
4
,
1 ;'
'' /
、
.' t・
、、
、.
9
270 KatsuraMoRIMoToandHiroakiKoJIMA
(1962),whospeculated theirprogressivedifferentiation in theade1ognathousCur_
culionidae.Distalpartofcoxiteisprominentasapairofprocessesfromtheproximal
mambranouspart intheSitoniniandOttistirini,whereasintheElytruriniandCeleu_
thetini, itembraces thevaginaandnotprominent.Theovipositor isslender in the
Celeuthetiniandcapableofstretchingmorethanwholebodylengthwhenovipositing.
Inthiscase,thespermathecaisdrawnintothetubularextendedpart.
KeytotheTribesandSubtribesinQuestion
1(4) Metendostemitewithlateralarms(Fig61);ovipositorveryshort,distalpart
ofcoxiteprominent caudad fromproximalmembranouspart(Fig 62),
bursacopulatrixwellbulged(Fig 53);8thsterniteinfemalewithspicu_
tumventrale(Fig 60).
2(3) Mandiblesofphanerognathoustype,withalmost flatandobliqueinnersur_
face,withdeciduousprocessatapexofleftmandible,whichdirectsinter_
nattyanditsscarsmallcrescentatapex;maxillaewithgaleaandlacjnja
distinct;pro-andmesocoxa1cavitiesconnateinternally. ...TribeSitonini
3(2) Mandiblesofade1ognathoustype,innersurfacefacedtotheopposite,deeply
concave; deciduousprocess indefinite; maxillaewithgaleaand lacinja
fused;pro-andmesocoxa1cavitiesentirelyseparatedbothexternallyand
internally TribeOttistirini
4( l ) Metendosternitewithoutlateralarms(Figs.10,52);ovipositorshorttolong,
distalpartofcoxitecontinuouswithproximalpartandembracevagina
betweenthem(Figs 9,21).
5(6) MetendostemiteT-shaped,anteriorpartentirelyflat,transverse,roundedlat_
e「allyandconglutinatetomesosterniteatthreepoints,themiddleofante_
riormarginandat theposteriorwallofmesocoxa1bowls,anteriorarms
andanterior tendonsabsent (Fig 57);ovipositorshort,bursacopulatrjx
wellbulged,reachingcephaladthelevelofsecondventrite(Fig53);8th
sternitein femalewithspiculumventrale(Fig 55);rostrumwithouttrans_
versesulcusatbase;hindtibiaewithouterbevel(=corbelenclosed)_ _
TribeElytrurini
6 (5) Metendosternite with anterior arms, anterior tendons widely distant, free
frommesosternum(Figs.10,52);ovipositorslender,spermathecalduct
very long(Figs 9,21).
7(8) Metendostemitewithventrallongitudinal angestronglydeveloped,promj_
nentanteriorlyasanarrowprocessfromthemiddleofanterjormargjnjn
Fi9S.15-22. - 15-19.Legs;15,16,N'easphalmusokinawanus(15: foreleg, l6:hindleg);17,18,
1sopteruskotoensls(17:foreleg,18:hindleg);19,hindlegoflsopte,-usmacromerus,showjngsten_
do「femurandcharacteristictooth. - 20,21.Arr/laphogaste1-pi1osus, female;20,abdomenrelaxed
With KOHSolution;21, ovipositor inabdomen,semidiagrammatica1. - 22. Metendostemjte of
/sopre,・usmao,,erne,-l,s.
NewSubtribeoftheCeleuthelini
271
272 KatsuraMoRIMoToandHiroaki KoJIMA
dorsalaspect,anterior armsreachingmesocoxalbowls; ovipositor with
distalpartsclerotized,proximalpartmembranouswithsclerotizedstripe
atside, bursacopulatrixshort;venterin femalewith7th tergiteterminal,
wholly covering 8th, 8thstemiteconcealed inside the 7th, withslender
spiculumventrale;mandibleswithoutdeciduousprocess,otherstructure
oftypicalade1ognathoustype TribePachyrhynchini
8(7) Metendosternitewithanteriormarginstraightorshallowlyconcave;oviposi-
tor very long, reachingbasallytomesosternum,distalpart divided into
twosclerotizedpart,proximalpartmembranous, longandbellows-like
(Fig 9);bursacopulatrixindiscernible;mandibleswithdeciduousprocess,
oftypicalade1ognathoustype Tribe Celeuthetini
9(10) Rostrumwithtransversesulcusatbaseseparatingdorsalfromhead(Fig.25);
8thstemitein femalewithdrawninside7th, withslenderspiculumven-
trale(Fig 50);8thtergiteinfemalepartlycoveredby7thatbase;9thster-
niteinmaleconsistingofasclerite. ........SubtribeCeleuthetinas.str.
10(9) Rostrumwithouttransversesulcusatbase(Fig3);8thsterniteinfemaleter-
minal(Figs 8,20),withoutspiculumventrale(Fig.13);8thtergiteinfe-
malealso terminal,uncovered; 9thsterniteinmalesubdividedintothree
sclerites SubtribeIsopterinanov.
Tribe Celeuthetini LAcoRDAIRE. 1863
Mandibles withdeciduous appendages, with three setae in general; antennal
scrobesdorso-1atera1or lateral,narrowtriangularorbifurcate,ventral furrowrunning
downobliquelyinfrontofeyetotheventrolateraledge;rostrumwithoutpterygia;an-
tennaewithscapelong,exceedingposteriorlybeyondtheanteriormarginofpronotum
when rested, 7-segmented in funicle,clubmuch shorter than funicle; postmentum
shortly pedunculate;prementumaboutas longasbroa labial palpi attached to the
innersurfaceof itsapicalmargin;maxillaepartlyvisiblebetweenlabiumandhypo_
stoma, galeaand lacinia fused. Prothoraxwithout ocular lobes.Procoxaeoften nar_
rowlyseparated,butcoxalcavitiesconnateinternally;mesocoxaeseparatedexternally,
butconnateinternally.Metacoxaewidelyseparated,contiguouswithelytraatsides.
Mesepimeramuchreduce(i, remote fromthebaseofelytra. Metendostemitetrans_
verse, without lateral arms, anterior tendonswidely distant. Hind tibiaewith inner
angeat apex (corbelsemienc1osedauct).Clawssimple, free. Aedeagus1ong, its
Figs.23-38. - 23-26.RostrumandheadofCeleuthetini;23,Platyspatuslatiscapus(exSulawesi);24,
25,Phuicoptuswalton1(exMindanao);26,Phraotesnodifer(exSulawesi). - 27-30.Antennal fu_
nicleofNeasphalmusspp;27,29,N rotundipennis(27:exKuchinoshima1.,29:exOkinawa_Honto
1.);28,N.okinawanus;30,N. ihai (ex. Ishigaki1.). - 31-38.SpermathecaofNeasphalmusspp.
andlsopterusspp;31,32,Nokinawanus(31:exTakarajima1.,32:exNakanoshima1.);33,34,Nro_
tundipennis(33:exIejima1.,34:exKuchinoshima);35,N.ihai(ex.Ishigaki1.);36,1.kotoensjs;37,I
variabais;38,1.macromerus.
273
jbeoftheCeleuthetm1
Newsub
274 KatsuraMoRIMoToandHiroakiKoJIMA
struts almost reaching cephalad to or beyond the anterior margin of mesothorax.
Ovipositor also long, reachingcephaladtotheanteriormarginofmesothorax,bursa
copulatrixnotdifferentiatedaspouch,spermathecalductlong,meander.
SubtribeCeleuthetinas.str.
=CoptorrhynchinaVoss,1940
=PlatysparinaVoss,1940
=Celeuthetini:MARSHALL,1956
Rostrumwithsulcusat baseseparatingtransversely fromhead.Femaleventer
withfive, fourortwovisiblesegments(ventrites),8thstemitewithspiculumventrale,
setoseatapex;9thstemiteinmaleconsistingofasclerite,undivided.
SubtribeIsopterinanov.
Typegenus: IsopterusFAUST,1895.
The other genera included: Arrhaphogaster RoELoFs, 1873; Neasphalmus
NAKANE,1963;PseudottlstiraHELLER,1934.
Mandibleswithscaralittlebelowthemid-lineofoutermargin,withdorsal,api_
calandventralteeth,with3-5setae,notscaled;postmentumshortlybutdistinctlype_
dunculate,prementumaboutaslongasbroacLlabialpalpiattachedtotheinnersurface
ofapicalmargin,closetoeachotherinposition,two-segmented;maxillaepartlyex_
pose galeaandlaciniafused.Rostrumnotdelimitedposteriorlybytransversesulcus,
shallowlyandbroadlydepressedandbarebehindepistometoantennalsockets;anten_
na1SCrobesdorso-1atera1(Arrhaphogaster)orlateral,withorwithoutdefiniteoblique
sulcusfromantennalsocketinadditiontothedorsolateralsulcus.Antennaewithscape
reachingpronotum, funicle7-segmented,basal twosegmentsslender.Pronotumwith_
outocular lobes.Elytrawhollycoveringabdomen,with10cr t2regularstrjae.pro_
andmesocoxalcavitiesnarrowlyseparatedexternally,butcontinuousinternally.Legs
withhindcoxaeratherbroadlytouchingelytra; femoraclavate,tibiaemucronate,cor_
betswithinnerflange(=semienc1osed),tarsiwith3rdsegmentdeeplybilobate;claws
simple,free.Ventervisibly5-segmentedinmale,firstandsecondventrjteslarge,sec_
endlongerthanthirdand fourthcombined,9thstemitesubdividedintothreesclerites;
infemaleventervisibly2-segmentedand8thstemitewithoutspiculumventrale
Me_
tendosternitetransverse,withoutlateralarms,anteriortendonsattachednearapex.
Amon9the9enerainIsopterina,Arrhaphogaster isapparentlyisolated fromthe
「est,andIsopterusincludesmorediversespeciesthantheothers.Thearrangementof
the9enerainthefollowingkeycanberegardedasthereflectionoftheirphy1ogenetjc
relationship.
KeytoGeneraoftheSubtribeIsopterina
1(2) Elytrawith12striae;antennalscrobesdorso-1atera1inposition,renjformjn
dorsalaspect,withshort,shallowandweakobliquesulcusbelowantennal