Cyclocephala melanocephala (Fabricius, 1775) (Coleoptera: Scarabaeidae: Dynastinae), identification key and remarks on known immatures of Cyclocephalini species

REVISTA

BRASILEIRA

DE

Entomologia

Systematics,

Morphology

and

Biogeography

Mating

behavior

and

description

of

immature

stages

of

Cyclocephala

melanocephala

(Fabricius,

1775)

(Coleoptera:

Scarabaeidae:

Dynastinae),

identification

key

and

remarks

on

known

immatures

of

Cyclocephalini

species

Sérgio

Roberto

Rodrigues

,

Carlos

Aparecido

Ferreira

Barbosa

,

Juares

Fuhrmann

,

Ricardo

Aparecido

Amaro

a_{UniversidadeEstadualdeMatoGrossodoSul,Cassilândia,MS,Brazil} b_{UniversidadedeSãoPaulo,MuseudeZoologia,SãoPaulo,SP,Brazil}

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t

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e

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o

Articlehistory:

Received26February2018 Accepted3July2018 Availableonline12July2018 AssociateEditor:MarcelaMonné

Keywords: Flyingactivity Morphology Scarabaeoidea Taxonomy Whitegrub

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MatingbehavioranddescriptionofimmaturestagesofCyclocephalamelanocephala(Fabricius,1775) (Coleoptera:Scarabaeidae:Dynastinae),identificationkeyandremarksonknownimmaturesof Cyclo-cephalinispecies.SomespeciesofCyclocephalaDejean,1821areregardedasrhizophagouscroppestsand othersasbeneficialspecies.Theobjectiveofthisworkwastoreportthematingbehaviorandtodescribe theimmaturestagesofC.melanocephala.ThestudiesweredevelopedattheUniversidadeEstadualde MatoGrossodoSulinCassilândia,MatoGrossodoSulstate,Brazil.Adultswerecollectedwithalight trapfromSeptembertoDecember2014and2015tocarryoutstudiesofmatingbehavior,breeding,and descriptionsofimmaturestages.Copulationlasted10.4±4.3minandtookplacefrom19:00to24:00h.

Somefemalesrefusedmalesformatingandmovedawayfromthem.Regardingflightperiod,adultswere collectedinlargerquantitiesfrom20:00to23:00h.Identificationkeystoimmaturesofthreegeneraof Cyclocephalini,includingseveralCyclocephalaspeciesarepresented.

PublishedbyElsevierEditoraLtda.onbehalfofSociedadeBrasileiradeEntomologia.Thisisanopen accessarticleundertheCCBY-NC-NDlicense(http://creativecommons.org/licenses/by-nc-nd/4.0/).

IntheCyclocephalinitribe(Coleoptera,Scarabaeidae, Dynasti-nae)about500describedspeciesareknownandofthese,morethan 85%arerepresentedbyCyclocephalaDejean,1821(Ratcliffeetal., 2013).CyclocephalaoccurfromsoutheasternCanadatoArgentina andtheAntilles(Ratcliffe,2003).InBrazil83speciesarerecorded

(Morón,2004).

Adultsfeedonplantsandflowers,thuscontributingto pollina-tion.Someexamplesofthebenefitstoplantsaredescribedtosome Araceae.Maiaetal.(2013)inastudiesconductedinAtlanticForest ofPernambucoState,foundthatflowersofTaccarumuleiEngl.& K.Krause(Araceae)arepollinatedexclusivelybyC.cearaeHöhne, 1923andC.celataDechambre,1980.InflowersofCaladiumbicolor

(Aiton)Vent.(Araceae)observedinAtlanticRainforestof Pernam-buco,Maiaand Schlindwein(2006)foundadultsofC.celata,an

importantpollinator,feedingandmating.Cyclocephalapollinators arealsoimportanttosomeAnnonaceae.InCerradoofGoiásState,

Cavalcanteetal.(2009)foundthatC.atricapillaMannerheim,1829,

∗ Correspondingauthor.

E-mail:sergio@uems.br(S.R.Rodrigues).

C.latericiaHöhne,1923andC.octopunctataBurmeister,1847are

floralvisitorsandpollinatorsofAnnonacrassifloraMart.Moreover,

Costaetal.(2017)conductedstudiesintheCerradoofMatoGrosso

StateandfoundthatC.atricapillaisthemainpollinatorofA.coriacea

Mart.,whileC.octopunctata,C.ohausianaHöhne,1923andC.undata

(Olivier,1789)aresecondarypollinators.InadditiontotheAnnona

L.speciescitedabove,Gottsberger(1989)notedC.atricapillaalso asapollinatorofA.dioicaA.St.-Hil.andA.monticolaMart.,and

C.quatuordecimpunctataMannerheim,1829asapollinator ofA.

cornifoliaA.St.-Hil.andA.tomentosaR.E.Fr.

SpeciesofCyclocephalaarealsofoundinotherplantfamilies, liketheexampleofDieringeretal.(1998,1999)whofoundadults ofC.caelestisDelgado&Ratcliffe,1990feedingandpollinating flow-ersofMagnoliatamaulipanaVázquez(Magnoliaceae)inMexico.In

MatoGrossodoSulState,Brazil,adultsofC.forsteriEndrödi,1963 werefoundfeedingoninflorescencesofAcrocomiaaculeata(Jacq.) Lodd.exMart.(Arecaceae)(OliveiraandÁvila,2011).Inarecent study,MooreandJameson(2013)related80speciesofCyclocephala

associatedwithflowersofvariousspecies.

TheimmaturestagesofCyclocephalaspeciesremaininthesoil andsomespeciesfeedonorganicmatter,asC.flavipennisArrow,

https://doi.org/10.1016/j.rbe.2018.07.001

Figs.1–4.Cyclocephalamelanocephala,adult;1,2,habitus(male,female);3,4,protibiaandtarsus(male,female).Scale:1,2=5mm;3,4=1mm.

1914observedinRioGrandedoSulStatebySalvadoriandPereira

(2006)andC.paraguayensisArrow,1913observedinthe

Pernam-bucobyAlbuquerqueetal.(2014).

However,in some species, larvae canfeed onroots of crop plantsandcausedamage.LarvaeofC.lunulataBurmeister,1847and

C.fulgurataBurmeister,1847appearassociatedwithonioncrops (AlliumfistulosumL.,Amaryllidaceae)andgrasses(Pennisetum clan-destinumHochst.&Chiov.,Poaceae),observationsmadebyVillegas

etal.(2006)inColombia.Whenlarvae,CyclocephalaparallelaCasey,

1915isconsideredanimportantpestofsugarcane(Saccharum offic-inarumL.,Poaceae)inFlorida,UnitedStates(GordonandAnderson,

1981;Cherry,1985),aswellasC.lunulatainMéxico(Aragón-Garcia

andMorón,2000).Also,C.forsteriandC.verticalisBurmeister,1847

werereporteddamagingsugarcanecropsinMatoGrossodoSul

(Coutinho et al.,2011).Cherman etal. (2014)reportedC.

mod-estaBurmeister,1847,C.putridaBurmeister,1847andC.tucumana

Brèthes,1904associatedtotherootsystemofseveralwintercrops inRioGrandedoSul.SantosandÁvila(2007)reportedthe occur-renceoflarvaeofC.forsterifeedingonrootsofsoybean(Glycine max(L.)Merr,Fabaceae)inMatoGrossodoSul.Dependingonthe circumstances,evenspeciesthatarenotusuallyconsidered eco-nomicallyimportantcandamagesomecultures,asC.flavipennis

Arrow,1914(SalvadoriandPereira,2006;Duchinietal.,2017).

Cyclocephalamelanocephala(Fabricius,1775) occurs through-out most of the New World, as United States (Ratcliffe, 1992;

Bauernfeind,2001),Mexico(Ratcliffe,1992)andBrazil(Camargo

andAmabile,2001;Nogueiraetal.,2013;Tairaetal.,2014).Adults

aretypicallyfoundfeedingoninflorescenceofsunflowerplants

(HelianthusannuusL.,Asteraceae)(CamargoandAmabile,2001).

Tairaetal.(2014)foundinMatoGrossodoSul,adultsofthisspecies

causingdamagetoshootsofyoungplantsofrubbertrees(Hevea brasiliensis(Willd.exA.Juss.)Müll.Arg.,Euphorbiaceae). Regard-ingthebiologyofC.melanocephala,Nogueiraetal.(2013)observed thattheegg-adultcyclewascompletedin113daysonaverageand morethanonegenerationispossiblyformedperyear.

DespitethespeciesrichnessofCyclocephala,immature descrip-tionsarescarce(Morónetal.,2014).Thus,studieswereconducted toverifythematingbehavioranddescriptionsofimmatureofC.

melanocephala.

Materialandmethods

Matingbehaviorofadults

Studiesonmatingbehaviorwereconductedonthe experimen-talfarmofUniversidadeEstadualdoMatoGrossodoSul(UEMS)in Cassilândia,MatoGrossodoSulState(MS).Tocollectadults,alight trap(model“LuizdeQueiroz”,SilveiraNeto andSilveira, 1969) wasinstalleddailyalongsidethepasturearea(Urochloadecumbens

Stapfcv.Basilisk,Poaceae)fromOctobertoDecember2014. Adultscollectedweretakentotheentomologylaboratoryof UEMS,separated bysex (firstpairoflegsin malesare dilated)

(Figs.1–4)andseparatedindividuallyin1000mLplasticcontainers

Afterthat,twenty-threecouplesweresortedfromtheadultsthat emergedfromthesoilandflewoff.Eachmaleandfemalewas gath-eredincouplesandputin500mLcontainersformatingbehavior observations.Theobservationroomwaskeptdarkaccordingtothe methodologyfromFacundoetal.(1999).Tovisualizeandrecord thebehaviorofmalesandfemales,aSony®

camcordermodel DCR-SX21STDwasused.

Tostudyadultflighthoursinthefield,alighttrapwasinstalled from18:00huntil06:00hof thenextday,fromOctober 30to November2,2014.At60-minintervals,thetrapwasinspected, andinsectscapturedwerecollected.Theflightscheduledatawere transformedinto√x₊1andsubmittedtotheanalysisofvariance

(ANOVA).Themeansweregroupedandcomparedbythe Scott-Knotttest(p<0.05)usingSISVARsoftware(Ferreira,2011).Dataon averagetemperature(◦_{C),precipitation(mm)andsolarradiation}

(kJ/m2_{)inCassilândia,wereobtainedfromtheInstitutoNational}

deMeteorologia(INMET).

Descriptionofimmatures

The described larvae were obtained from adults reared in thelaboratory.FromSeptembertoDecember 2015,adults ofC.

melanocephala were collected at the experimental farm of the UEMS,withlighttrap.Theadultswerecarriedtotheentomology laboratoryandformedcouples,whichremainedin1000mLplastic containerscontainingsoilandBrachiariadecumbensStapf(Poaceae) seedlings,andthecontainerswerecoveredwithvoilfabric.

Thevesselswereinspectedeverydaytofindeggsandtoremove the dead insects. The eggswere kept in Petri dishes, contain-ing sieved and moistened soil, and keptin an air-conditioned roominthelaboratory(26±2◦_{Candscotophase).ThePetridishes}

wereobservedatintervalsof twodays, andthehatchedlarvae weretransferredandindividualizedin500mLplasticcontainers containingsoilandB.decumbensseedlings(26±2◦_Cand12h

pho-tophase)(Rodriguesetal.,2014).

FromMaytoAugust2016,thirdinstarlarvaeandpupaewere killedinboilingwaterandpreservedin70%alcohol.The observa-tionsanddrawingsofthemorphologicalaspectsofthelarvaand pupawerecarriedoutinStereomicroscopeMotic,ZeissStemiSV 6stereomicroscopeorZeissAxioscopmicroscope,bothwithlight cameracoupled.Thedetachedstructuresofthelarvalbody(e.g. mouthpartsandlegs)wereslidemountedinHoyer’s(Johnsonand

Triplehorn,2005).TheadultsofC.melanocephalaweredeposited

in the UEMS entomology collection in Cassilândia; the imma-turewasdepositedinthecollectionoftheMuseudeZoologiada UniversidadedeSãoPaulo,SãoPaulo(MZSP).AdobePhotoshop CS6softwarewasusedforimageprocessinganddrawingofthe plates.

The terminology used follows Böving (1936) and Lawrence

(1991)withsomemodificationsbySousaetal.(2018).Theterms

helus(toothor fixedand rigid cuticular process)and phoba(a groupofflexiblefixedcuticularprocesses)wereusedforboth epi-andhypopharynx.Theepipharynxareasubdivisions(corypha, hap-tomerus,paria,pediumandhaptolachus)areinitalictomakeit easiertofind.HeadchaetotaxyfollowsRitcher(1966)andSawada

(1991)assummarizedbySousa etal.(2018).Mandiblesincisor

usuallyhave3definedteeth(S1,S2,S3;distaltoproximal),and S2–S3separationisnotedbytheincisornotch(Figs.17,22).Even whenS2isreduced,thenotchiseasytofindanddefinestheS2and S3area.Besidesthesethreeteeth,aproximalmostincisortooth mayoccur(S4)betweenS3andmolar(onmandibleinnerconcave margin).

Hair-likesetaearetermedas(modificationofˇSípeketal.,2008): minute,when itslengthisat mostthreetimeslongerthanthe diameterofassociatedpuncture(barelydistinctunder magnifica-tionlessthan40×);shortorlongwhenitslengthisatleastfour

timeslongerthanthediameterofassociatedpuncture(easily vis-ibleundermagnificationof20×).Longandshortsetaeareonly

differentiated when conspicuous relative differencesoccur (e.g. rastersetae,Figs.43, 44),otherwise (i.e.wide setallength vari-ation)theoppositionminute/longformerlydefined isused(e.g. cranialsetae,Fig.7).Thelarvaesizecouldaffectthevisibilityof minuteandlongsetae,butdifferencesinrelativesizeandspatial distributionhelptoseparatebothsetaegroup.

Headchaetotaxywaswidelyusedasdiagnosisinscarab imma-tureworks,whilethoracicandabdominalchaetotaxy(exceptfrom raster)werenotorpartiallydescribed(e.g.JamesonandMorón, 2001describedthedorsallobessetation).Toexplorethebodysetae asanidentificationtool,thethoracicandabdominalsetationwere describedandillustrated(Fig.14).Thisuncommonapproachadds newdata andencourage future works toinvestigatetheentire bodychaetotaxy.Chaetotaxyweregiventoeachbodylobe.Terms likescutum,scutellum,presternum,sternum,andderivedterms areavoidedbecausethehomologybetweenlarvallobesandadult sclerites are doubtful,and the ventralbody surface hassternal andpleuralelementsinColeoptera(Kobayashietal.,2013).The resulting lobes terminology is as follows (Fig. 14): thorax dor-sum:anterior,medial,andposteriortergallobes;thoraxlateral: anteriorandposteriorpleurallobes;thoraxventer:anteromedial andposterior ventrallobes; abdomendorsum:anterior,medial, lateralandposteriortergallobes;abdomenlateral:anteriorand posteriortergallobes,andspiraclelobe;abdomenventer:anterior, medial,andposteriorlobes.Whenthislobedivisionisindistinct (e.g.Scarabaeoideapronotumhave1–3lobesandabdomen seg-mentIX usuallyhasanundivideddorsumand asimple pleural lobe,Ritcher,1966),ageneralpositionnameisgiventotheregion ifnecessary.Thechaetotaxytoprothoraciclateralscleriteisalso givenandthelobesnamesarenotappliedtoabdominalsegment X,becauseitsalreadyhasaparticularterminology(rasterandanal lobes).

The proposed identification keys and comparative table

(Table1)includedherein use newdata and information

avail-able in thebibliography (Albuquerque et al., 2014; Branet al.,

2006;Garcíaetal.,2009;Johnson,1941;King,1984;Morelli,1991;

Morelli andAlzugaray, 1994;Morón etal., 2014;Neita-Moreno

andYepes,2011;PereiraandSalvadori,2006;Remedi-de-Gavotto,

1964;Ritcher,1966;Souzaetal.,2014a,b;Vincinietal.,2000).

Results

Cyclocephalamelanocephala(Fabricius,1775)

Thirdinstarlarva(Figs.5–44).Body(Fig.5)length:19–26mm; grayishoryellowish white,headand respiratoryplates yellow-ish brown; surface densely setose, setae yellowish brown to brown. Head (Figs. 6, 7, 13) width: 2.8–3mm; epicranial and epistomalsuturesdistinct;stemmataverysmall;antennifer some-what cylindrical and with 3 punctures; cranium, clypeus and labrum(Figs.7,8)withmanyhomogeneouslydistributed punc-tures, except in labralanterior area. Each half of cranium and clypeuswith(Fig.7):4–3longand2–3mindorsoepicranialsetae (des)ina row and1minseta internallypositioned,2 longand numerousminuteposteroepicranialsetae(pes),2–3long anteroep-icranialsetae(aes),5–8longexternoepicranialsetae(ees),2–3long and 1min posterofrontal setae(pfs), 1 long externofrontalseta (efs),2–3longanterofrontalanglesetae(aas),2longanterofrontal setae(afs),2longexternoclypealsetae(ecs),1longanteroclypeal seta (acs). Labrum(Fig. 8): each half with 2–3long and 1min

Table1

ChaetotaxyoftheknownthirdinstarsofCyclocephala.

Species Parietals Frons Clypeus Labrum Raster

des pes aes ees pfs efs aas afs acs ecs pls lls mls als tg* _pr* _{pa al}*

C.barrerai 2–3 3 ∼3 ∼4–5 2 0 1 1 0 1 3–4 ∼2 1 – 21–23 u 0 30–32

C.borealis 2–3 – – – 2 1 1–2 1–2 – – – – – – ∼25 u 0 20

C.celata 4 – – – 2 1 2 3 1 2 4–5 4 1 – 14–16 u 0 –

C.comata 2 2 2–3 – 2–3 0 – 0 1 1 2–4? – 1 – 10–12 u 0 48–50

C.disticta 3–4 5–6 – – 4–5 1 2 2 1 1 3–4 ∼4 1 2 7–9 u 0 ∼22

C.fasciolata 3 2 2–3 – 1–2 0 1 0 1 1 0 3 1 – 0 [8–9] u 0 26–28

C.flavipennis – – – – – – – – 1 1 – – – – 13–16 u 0 ∼22

C.fulgurata 3–4 5–6 2–3 ∼8 2 1 1 1 1 1 – ∼3 1 – 12–15 u 0 34–38

C.gregaria 1 1 2–3 ∼3 2 1 1 1 1 1 – ∼2 1 – 19–22 u 0 30–35

C.jalapensis 3 2 2–3 – 1 0 1 0 1 1 0 3 1 – 0 [16] u 0 0 [26]

C.longula(=C.abrupta) 7–8 – – – 3 1 2 2 – – – – – – – u 0 –

C.lunulata 2–4 5–61** _{2–3 ∼5 2 1 1 1 1 1 7–8 ∼2–3 1 – 10–1620–28! u 0 26–34∼20!}

C.lurida(=C.immaculata) 3 ∼2 ∼3 ∼8 2 1 1 1 1 1 0 ∼4 1 2 13–16 u 0 ∼35 C.melanocepala 3–4 2 2–3 5–8 2–3 1 2–3 2 1 2 2–3 4–5 1 2 8–11 1–2 3–4 28–34

C.modesta – – – – – – – – – – – – – – 11–13 2–3 6–8 ∼25

C.paraguayensis 5 ∼5 ∼1 ∼8 1 1 2 1 1 2 1 ∼2 1 ∼15 4–5 3–4 ∼37

C.pasadenae 3–5 – – – 2–4 1 1 – – – – – – – ∼15 u 0 –

C.putrida – – – – – – – – – – – – – – ∼20 u 0 ∼37

C.signaticollis 3 2 3 – 1 – 3 1 1 1 – – – – 13–16 u 0 20–30

C.sinaloae 3–4 3 ∼3 ∼4–5 2–3 1 1 1–2 1 1–2 2–3 2–3 1 – 14–17 u 0 59–62

C.testacea 4 1 5–6 ∼8 – 1 – 2 1 3 5 – 1 – 28–30 0 ∼33 –

Thechaetotaxyisgivenforonesideofthestructure,exceptforventralanallobe(al).*onlyhamatesetaequantified,ifhamatesetaeabsentthenumberofhair-likesetaeisgiven betweensquarebrackets.“u”unapplieddata(i.e.whenpalidiaisabsent,itisimpossibledefinethepreseptularsetae).“∼”about.Cyclocephalalunulata:generalchaetotaxyby

Branetal.(2006);**redescriptionofMorónetal.(2014)recordedonly1pes;!firstcharacterizationbyKing(1984).aas,anterofrontalanglesetae;acs,anteroclypealsetae; aes,anteroepicranialsetae;afs,anterofrontalsetae;al,ventralanallobesetae;als,anterolabralsetae;des,dorsoepicranialsetae;lls,laterolabralsetae;mls,mediolabral setae;ecs,externoclypealsetae;ees,externoepicranialsetae;efs,externofrontalsetae;pa,palidiumsetae(pali);pes,posteroepicranialsetae;pfs,posterofrontalsetae;pls, posterolabralsetae;pr,tegillumpreseptularsetae;tg,tegillumsetae(includingthepreseptularones).

Figs.5–6.Cyclocephalamelanocephala,thirdinstarlarva;5,lateral;6,head,dorsal.t10,abdominaltergiteX;usb,U-shapedsclerotizedbar.Scale=1mm.

width=2.1)and with5sensilla(1dorsal,1internal,1 external, 2ventral);IIlong(l/w=2.3–2.5)andwith9–10sensilla(3–4 dor-soproximal,2ventroproximal,4ventrodistal);IIIshort(l/w=1.3) andwith10 sensilla(2dorsoproximal, 2internal, 4external, 2 ventral),ventrodistalprocessbearingadorsalsensorialspotand 2distalsensilla;IVlong(l/w=2.8),with6sensilla(4external,2 ventral),2dorsaland2ventralsensorialspots,andadistal sen-sorialareabearingabout9prominentminutesensilla.Epipharynx

(Figs.15,16).Corypha:epizygumdistinctandclythraabsent.

Hap-tomerum:zygumbeak-like,2-toothedandwithabout10sensilla; heliabsent.Paria:acropariaevidentlyseparatedfromchaetoparia and each side withabout 13 setae; each side of acanthoparia with9–11anteriorsetaeand8–9minposteriorsetae;gymnoparia narrow;rightchaetoparia withabout95 setae,left chaetoparia withabout70setae;dexiotormatwicelongthanlaeotorma,left

pterotormarounded,aptormaindistinct,epitormaasanimpressed roundedsulcus;plegmatia,proplegmatiaandphobaabsent.Pedium

des pes ees aes pfs f j h g i k j h j i i k I m k n q s p p p q q r

11

10

9

12

f a ae

b

b a b

afs pls mls als lls lls

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7

Figs.7–12.Cyclocephalamelanocephala,thirdinstarlarva;7,craniumandclypeus,dorsal;8,labrum,dorsal(epipharyngealventralsetaeomitted);9–12,leftantenna(dorsal, internal,external,ventral;externalandinternalsideswithapexdetail;somesensillanumberedtoeasilythecorrespondence;sensillumhcanbeabsent).Chaetotaxy(italic) onthetext.Scale=0.5mm(antennaldetailswithmagnificationfourtimesbiggerthanantennae).

setae.Leftmolarwith9dorsoproximalsetaeinarow,3 ventro-proximalsetaeinatuft;2anteriorchisel-liketeethtransversally positionedtoeachother,adorsalandaventraltooth,2 transver-salshallowcarinaebetweenthedorsalandventralteeth;aciawith apexroundedandbearingabout6setae;calxsemicircular;brustia with12setae.Maxillae(Figs.23–25).Galeaandlaciniaseparated bysuture;galeawithanuncus;laciniawith3unci;mala with-outconspicuoussetaerow.Stipewithstridulatoryareabearing13 obtuseteethandadistaltruncateprocess.Palpwith4palpomeres: Iwithanexternoproximalsensillumandaminuteexternodistal seta;IIwithanexternodorsalsensillumand3ventralsensilla;III withanexternalseta,aventralsetaand2ventralsensilla;IVwith 3externalsensillaandaninternodistalminuteseta,distal senso-rialareabearingabout13sensilla.Hypopharynx(Figs.16,24)with asymmetricalsclerite,rightandleftlateralwithabout14setae(7 long,7min),lateromedialleftareawitharowofabout22stout setae,lateromedialrightareawithagroupofphobae;right ante-riorareawithaprominenttooth,posteriorareawithaprominent semisphericalprocess.Posteriorpreoralarea:eachsideofdorsal area(posteriortoepipharynx,Fig.15)withasensillum;eachside ofventralarea(posteriortohypopharynx,Fig.24)with2sensilla, rightareawithananteriorstoutseta,leftareawitharowofabout23 stoutsetae.Labium(Figs.16,24,25).Submentumwithaposterior scleritebearing1setaeand4–5sensillaoneachside,anteriorarea with2setaeandasensillumoneachside.Mentumwithaglabrous scleritemediallyinterrupted,anteriorareawith7–8setaeand1–4 sensillaoneachside.Prementumwithascleritebearing6–8setae distributedaroundpalpiinsertion;ligula(Figs.16,24)with3large medialsetaeoneachside,16smallposteriortooth-likesetae,a smallmedialtubercle-likeprocess,aposteriortransversalsclerite, posteriorareabearingasperites.Palpwith2palpomeres:Iwitha minuteventroproximalseta;IIwithaventrodistalsensillum,distal sensoryareawithabout13sensilla.Thorax(Figs.5,14). Protho-raxwithatergallobebearing40–50thinsetae(setaesimilarto

Fig.44d),anteriorpleurallobewith4–5thinsetae,posterior pleu-rallobewith9–17,prothoraciclateralscleritewith6–8thinsetae, anteromedialventrallobewith46–54,posteriorventrallobebare. Meso-andmetathoraxwithanteriortergallobebearing15–19thin setae,medialtergallobewith44–60thinsetae,posteriortergallobe with16–20thinsetae,anteriorpleurallobewith4–7thinsetae, posteriorpleurallobewith2–4thinsetae,anteromedialventral lobewith34–40thin setae,posterior ventrallobewith2setae.

Legs(Figs.26–28).Pro-,meso-andmetafemurinternodistalarea

withasmallandacutetuberclebearingadistalseta,meso-and metafemurwithanexternodorsalmacula;pretarsuswith2 lat-eroventralsetaeandanacuminateapex,propretarsuslongerthan meso-andmeso-longerthanthemetapretarsus(Figs.29–31). Tho-racicspiracle(Figs.32–34)with11–14perforationsindorsalradius (DR),6–8inlateralradius(LR),13–16perforationsinventralradius (VR);perforationsoblongorslightlyameboidshaped;bullaslightly largerthanthedistancebetweenrespiratoryplatearms.Abdomen

(Figs.5,14):AbdominalsegmentIwithanteriortergallobebearing

hyr

ant mda

mdc

hyt tnt mlf th1

th2

th3

ab1

esl pal

ppl

ab7

ab8 ab7

ab8

ab9

ab10

ab10

usb ab9

14

tpl tml tll val

vml vpl ab2

ab1 th3

th2 th1

tal

13

Figs.13–14. Cyclocephalamelanocephala,thirdinstarlarva;13,head,ventral(leftsidewithsubmentumandcardo);14,distendedbodytegument(hair-likesetaerepresented bytheirpuncture,abdominalsegments3–7omitted).ab1–10,abdominalsegment1–10;ant,antennifer;esl,spiraclelobe;hyr,hypostomalrod;mda,cranio-mandibular acetabulum;mdc,cranio-mandibularcondyle;mlf,maxillolabialcomplexforamen;pal,pleuralanteriorlobe;ppl,pleuralposteriorlobe;tal,tergalanteriorlobe;tll,tergal laterallobe;tpl,tergalposteriorlobe;tnt,tentorium;th1–3,pro-,meso-andmetathoracic;usb,U-shapedsclerotizedbar;val,ventralanteriorlobe;vml,ventralmediallobe; vpl,ventralposteriorlobe.Scale=0.5mm.

medialventrallobewith5–7thinsetae,posteriorventrallobebare. AbdominalsegmentVIIIsimilartoVII,buttergallobewith25–28 thinsetae.AbdominalsegmentIXwithatergallobewithan ante-riorgroupof10–15thinsetaeandaposterolateralgroupof21–24 thinsetae,apleurallobewith14–17thinsetae,anteriorventral lobebare,posteriorventrallobewith4medialthinsetaeand2–4 lateralthinsetae.SegmentX(Figs.5,14,43)withacurvedanal opening,tergitewithananteriorU-shapedsclerotizedthinbar,a groupofabout170–180anteriorthinsetaeandaposteriorgroup of46–61stoutsetae;ventralanallobewith10–15thinsetaeand 28–34hamatesetae.Spiracles(Figs.35–42):Ismallerthanother onesandwith6–8perforationsinDRandLR,and13–15inVR;II–VI

acr

aca

crp

ppa

crp

ppa

lip

15

16

Figs.15–16.Cyclocephalamelanocephala,thirdinstarlarva;15,epipharynx;16,cibarium.aca,anteriormostacanthopariaseta;acr,lateroposterioracropariaseta;crp,right partofcrepis;lip,ligulartubercle-likeprocess;ppa,posteriorpreoralarea.Scale=0.5mm.

S1 S2

inn

S3

S2

17

18

19

20

21

22

24

25

23

ppa

Figs.23–25. Cyclocephalamelanocephala,thirdinstarlarva;23,maxilla,internal;24,maxilla,hypopharynx,ligula,dorsal;25,maxilla,labium,ventral.ppa,posteriorpreoral area.Scale=0.5mm.

Remarks.LarvaeofC.melanocephalaandC.paraguayensisare easilydistinguishedfromotherknownCyclocephalinilarvaeby thepresenceofpalidiawithbifurcatesetae(Fig.44a).Thebody chaetotaxy(Table1)isusefulassupplementarydatatothespecies identification.

ForC.modestaandC.putrida,onlytherasterisknown.Morelli

(1991)providedimagesofthesespecies,rasterandattributedthe

originaldata to anunpublished thesis: “L. Alvarado. 1980. Sis-temáticay bionomía decoleópteros que enestados inmaduros vivenenel suelo.UniversidadNacional delaPlata.Facultad de CienciasNaturalesyMuseo,Argentina”.LarvaeofC.modestahavea peculiarraster(notseeninotherCyclocephalini)withpalidialong andposteriorlydivergent.Otherwise,larvaeofC.putridacannot bedistinguishedfromotherCyclocephala larvaeastherasterdo

notshowanyspecifiedpattern.Moredataaboutbothspeciesare neededtoclarifythelarvaetaxonomy.

ThirdinstarlarvaeofC.flavipennisandC.signaticollis Burmeis-ter,1847areeasilydifferentiatedfromotherCyclocephalinilarvae by ventral anal lobe ornamentation, both have posteromedial hamatesetaedistinctlybiggerthananterolateralsetae.Immature ofC.signaticolliswasdescribedbyRemedi-de-Gavotto(1964)and redescribedbyMorelli(1991),andlarvaeofC.flavipenniswerefirst timecharacterizedbyPereiraandSalvadori(2006).Untilnow,itis impossibletoseparatebothspeciesandmorestudiesareneeded tosolvethisproblem.

34

35

36

37

38

39

40

41

42

33

30

29

32

26

27

28

31

Figs.26–42.Cyclocephalamelanocephala,thirdinstarlarva;26–28,rightlegsandpleurites(anterior,medial,posterior);29–31,rightpro-,meso-andmetapretarsus,dorsal; 32–33,detailofperforationsofmesothoracicspiracle(dorsalarm,medialarea);34–42,mesothoracicspiracleandabdominalspiraclesI–VIII.Scale,Fig.26=0.3mm;Figs.29, 34=0.1mm;Fig.32=0.05mm.

a

_b

d

b

c

c

d

a

43

44

(Scarabaeinae;PaulianandLumaret,1972).However,the macu-laeofB.bubalushasaminutesetaandtwoslightlyglobosedark spots(maculaesmoothinC.melanocephala).

Material examined. Brazil, Mato Grosso do Sul, Cassilândia, experimentalfarmofUEMS,20.v.2016,leg.R.A.Amaro,6larvae (MZSP–10.356).

KeytoknownthirdinstarlarvaeofknownCyclocephalini(minutesetaeareomittedinthekey)

1–AntennomereIVwithoneormorethan2dorsalsensorialspots;zygumasacross-barorbeak-likewith1ormorethan2teeth;abdominaltergitesVIII–IXwithor withoutnumeroussmallstoutsetae...DynastinaeotherthanCyclocephalini 1′_{–AntennomereIVwith2dorsalsensorialspots;zygumbeak-likewith0or2teeth;abdominaltergitesVIII–IXwithoutsmallstoutsetae...Cyclocephalini.......2}

2(1)–Headwithoutanterofrontalsetae(afs);zygumtoothlessandwithposteriormargincrenulateorstraight;leftmandiblewithfourthscissortooth(S4 present)...3 2′_{–Eachheadsidewith0–2anterofrontalsetae(afs);zygum2-toothed;leftmandiblewithorwithoutS4....CyclocephalaDejean,1821(part).........................7}

3(2)–Headwithoutposterofrontalsetae(pfs);perforationsofthoracicspiracleameboidandbearingmorethan4sinuosities...AncognathamancaLeConte,1866 3′_{–Eachheadsidewith1–2posterofrontalsetae(pfs);perforationsofthoracicspiracleoblong,ifperforationsslightlyirregularshaped,thenthemwithlessthan4}

sinuosities...4 4(3)–Eachheadsidewith1anterofrontalangleseta(aas)...C.fasciolataBates,1888

4′_{–Eachheadsidewith2–4anterofrontalanglesetae(aas)...DyscinetusHarold,1869..................................................................................5}

5(4)–Eachheadsidewith4–5dorsoepicranialsetae(des)...D.morator(Fabricius,1798) 5′_{–Eachheadsidewith2dorsoepicranialsetae(des).......................................................................................................................6}

6(5)–Eachsidewith3–4anterofrontalangleseta(aas);haptolachusleftsidewithabout18setae...D.dubius(Olivier,1789) 6′_{–Eachheadsidewith2anterofrontalangleseta(aas);haptolachusleftsidewithlessthan10setae.................................. D.rugifrons(Burmeister,1847)}

7(2)–Palidiapresent,sometimespaliirregularlydistributedandseptulabarelydistinct,butpalieveneasilydifferentiatedfromtegillarsetae...8 7′_{–Palidiaabsent............................................................................................................................................................11}

8(7)–Eachpalidiumwithmorethan30setae...C.testaceaBurmeister,1847 8′_{–Eachpalidiumwithlessthan10setae...................................................................................................................................9}

9(8)–Eachpalidiumwith6–8acutesetae...C.modestaBurmeister,1847 9′_{–Eachpalidiumwith3–4bifurcatesetae(Fig.44a)......................................................................................................................10}

10(9)–Eachheadsidewith2–3posterofrontalsetae(pfs),2anterofrontalsetae(afs),2–3posterolabralsetae(pls)...C.melanocephala(Fabricius,1775) 10′_{–Eachheadsidewith1posterofrontalseta(pfs),1anterofrontalseta(afs),1posterolabralseta(pls)...................................C.paraguayensisArrow,1913}

11(7)–LeftmandiblewithS4...C.jalapensisCasey,1915 11′_{–LeftmandiblewithoutS4...............................................................................................................................................12}

12(11)–Ventralanallobewith7–9posteromedialhamatesetaetwicelargerthanotherhamatesetae(cf.Remedi-de-Gavotto,1964:Fig.8;PereiraandSalvadori, 2006:Fig.6b)... C.flavipennisArrow,1914andC.signaticollisBurmeister,1847(seeremarks) 12′_{–VentralanallobewithmedialsetaenotorslightlybiggerthanlateralsetaeORsetaeprogressivelylargertomedialarea,butsetaeenlargementneverabrupt...13}

13(12)–AbdominalspiracleIevidentlysmallerthanII–V...14 13′_{–AbdominalspiracleI–Vwithsimilarsize..............................................................................................................................17}

14(13)–Eachheadsidewithmorethan6dorsoepicranialsetae(des)...C.longulaLeConte,1863 14′_{–Eachheadsidewithlessthan5dorsoepicranialsetae(des)...........................................................................................................15}

15(14)–Eachheadsidewith1dorsoepicranialseta(des)and1posteroepicranialseta(pes)...C.gregariaHeyne&Taschenberg,1908 15′_{–Eachheadsidewith2–4dorsoepicranialsetae(des)and5–6posteroepicranialsetae(pes).........................................................................16}

16(15)–Maxillarystridulatoryareawith7teethandananteriortruncateprocess...C.lunulataBurmeister,1847 16′_{–Maxillarystridulatoryareawith9–10teethandananteriortruncateprocess..........................................................C.fulgurataBurmeister,1847}

17(13)–Ventralanallobewithmorethan45hamatesetae...18 17′_{–Ventralanallobewithlessthan40hamatesetae......................................................................................................................19}

18(17)–Eachheadsidewith2dorsoepicranialsetae(des),2posteroepicranial(pes)andwithoutanterofrontalsetae(afs)...C.comataBates,1888 18′_{–Eachheadsidewith3–4dorsoepicranialsetae(des),3posteroepicranial(pes)and1–2anterofrontalsetae(afs)...C.sinaloaeHowden&Endrödi,1966}

19(17)–Eachsideofrasterwith7–9hamatesetae...C.distinctaBurmeister,1847 19′_{–Eachsideofrasterwithmorethan10hamatesetae...................................................................................................................20}

20(19)–Eachsideofrasterwithlessthan17hamatesetae...21 20′_{–Eachsideofrasterwithmorethan18hamatesetae...................................................................................................................23}

21(20)–Maxillarystridulatoryareawith4teethandananteriortruncateprocess...C.celataDechambre,1980 21′_{–Maxillarystridulatoryareawithmorethan6teethandananteriortruncateprocess...............................................................................22}

22(21)–AbdominaltergiteXwithaU-shapedthinsclerotizedbar(similartoFigs.5,14),areaanteriortoscleromewithatransversalsetaegroup...C.lurida Bland,1863

22′_{–AbdominaltergiteXwithaU-shapedthinsclerotizedbar,areaanteriortoscleromebare................................................C.pasadenae(Casey,1915)}

23(20)–Ventralanallobewithabout20hamatesetae... C.barreraiMartínez,1969 23′_{–Ventralanallobewithabout30hamatesetae...................................................................................................C.borealisArrow,1911}

Pupa(Figs.45–51).Body(Figs. 45–47)length15.2–15.4mm;

thoraxwidth 7.1–7.5mm; whitish, integument macroscopically smoothandglabrousbutcoveredbyathinandshortmicroscopic pubescence,whichgivesavelvetyappearancetothesurface,this pubescenceslightly longer in abdomenlaterals. Head(Fig.48). Vertex hidden under pronotum from dorsal view. Epistomal suturedistinct laterally and indistinct medially. Canthussmall. Labrumshortandtransversal,positionedbetweenthemandibles. Maxillary palps prominent. Labium slightly rounded. Antenna withtwodefinedregions:scape-pedicelandfunicle-clava.Thorax. Pronotumwiderthanlong,greaterwidthattheposteriormargin, lateralmarginsrounded.Prosternumwithvisibleposteriorprocess betweenpro-andmesocoxae,processacuteinmales(Fig.49)and

roundedinfemales(Fig.50);precoxalareahiddenbytheheadin ventralview.Mesonotumas longaspronotumandlongerthan metanotum.Elytracurvedventrallyaroundthebodyandalmost smooth. Pro-, meso- and metacoxa contiguous; profemur-tibia slightlyexposed indorsalview;mesofemur-tibiasuperposedto wingsin ventralviewand hiddenin dorsalview;protibia with

45

46

47

Figs.45–47. Cyclocephalamelanocephala,femalepupa(dorsal,ventral,lateral).Scale=5mm.

48

49

50

51

posterior genital ampullae larger than long and with a distal impressedline;sterniteXslightlyexposed.

Remarks.PupaeofC.melanocephalaandC.paraguayensisare easilydistinguishedfromotherknownCyclocephalinipupae(see thekey below)by thepresence of 5 dioneiform organs, other cyclocephalinepupaehave4(C.signaticollis)or6organs.Morón

etal.(2014)characterizedpupaeofC.jalapensiswith6dioneiform

organs,moredataareneededtoseparatethisspeciesfromothers. ThelarvaeandpupaeofC.borealisArrow,1911werefirsttime describedandillustratedbyJohnson(1941),butmore morpholog-icaldataareneededtoseparateitspupaefromothers.

BesidestheCyclocephalaspecies,othertwospeciesof Dyscine-tusHarold,1869havetheirpupaedescribed.Dyscinetusrugifrons

(Burmeister,1847) pupawasdescribed byVincini etal.(2000), andD.dubiuspupa(Olivier,1789)wasdescribedbyNeita-Moreno

andYepes(2011).Apparently,pupaeofCyclocephalahavetergite

IXventralfoldhiddenmostofsterniteIXinlateralview(Fig.47), whileDyscinetuspupaehaveashorttergiteIXventralfoldandmost ofsterniteIXisexposedinlateralview(cf.Neita-MorenoandYepes, 2011:Fig.h).Moredataareneededtoconfirmthesedifferencesand toproposeanadequatediagnosis.

Material examined. Brazil, Mato Grosso do Sul, Cassilândia, experimentalfarmofUEMS,31.viii.2016,leg.R.A.Amaro,4females, 1male(MZSP–10.356).

KeytoknownpupaeofCyclocephala

1–Abdomenwith4dioneiformorgansbetweenIII–IV,IV–V,V–VI,VI–VII...C.signaticollisBurmeister,1847 1′_{–Abdomenwithmorethan4dioneiformorgans,organspresentbetweenI–IIandII–III................................................................................2}

2(1)–Abdomenwith5dioneiformorgansbetweenI–II,II–III,III–IV,IV–V,V–VI...3 2′_{–Abdomenwith6dioneiformorgansbetweenI–II,II–III,III–IV,IV–V,V–VI,VI–VII......................................................................................4}

3(2)–AbdominaltergiteVIIanteriormarginabout2.5timeswiderthantheposteriormostdioneiformorgan(betweenVI–VII)...C.melanocephala (Fabricius,1775)

3′_{–AbdominaltergiteVIIanteriormarginabout1.75timeswiderthantheposteriormostdioneiformorgan(betweenVI–VII)...C.paraguayensisArrow,1913}

4(2)–AbdominaltergiteXIventralfoldformingaposteriortubercle-likeprocessbearingsomerelativelylongsetae(cf.Souzaetal.,2014a:

Figs.16–18)...C.testaceaBurmeister,1847 4′_{–AbdominaltergiteXIventralfoldposteriorlyobtuseoracute,butneverwithatubercle-likeprominence............................................................5}

5(4)–AbdominaltergiteXIventralfoldposteriorlyacute...C.fulgurataBurmeister,1847 5′_{–AbdominaltergiteXIventralfoldposteriorlyobtuse.....................................................................................................................6}

6(5)–Profemur-tibiaarticulationareahiddenindorsalview...C.testaceaBurmeister,1847 6′_{–Profemur-tibiaarticulationareavisibleindorsalviewasasmallareanexttopronotumposteriorangleandelytralhumeralarea(similartoFig.45)...7}

7(6)–PubescenceofabdominaltergiteXIventralfoldalmosthiddenindorsalview,maleanteriorgenitalampullaslightlyconstrictedmedially...C.gregaria Heyne&Taschenberg,1908

7′_{–PubescenceofabdominaltergiteXIventralfoldevidentindorsalview,maleanteriorgenitalampullastronglyconstrictedmedially...C.lunulata}

Burmeister,1847

Matingbehaviorofadults

Severalstagesofmatingbehaviorwereobservedforthe23 cou-plesmatedinthelaboratory.Adultsremainedinthesoilduring theday.Atnightfall,males(n=18)andfemales(n=13)exposeda portionoftheclypeusnearthesoilsurfaceandmovedtheantennal lamellaeindifferentdirectionsfor5.2±2.1min(range3–11)before

theyleftthesoilandstartedtheflight.However,somemales(n=5) andfemales(n=10)arrivednearthesoilsurface,leftquickly,and begantofly(Fig.52).

Whentheyleft the soil, adults flewactively onaverage for 8±3.5min(range4–14)andthenbegantowalkonthesoilwith

theantennaeerectedandthelamellaeopen.Fourteenoutofthe couplesmatedshowedmultiplestagesofmatingbehavior,while ninecouplesshowednomatingbehavior.Atthefirststageof mat-ing,themaleapproachesthefemalefrombehind(n=9)touching theendoftheelytraorpygidiumofthefemalewiththeantennae andprotarsiortouchesthefemaleonherside(n=5).Whenthe maletouchesthefemale,possiblychemicalrecognitionbetween bothisoccurring;however,evidenceofapheromonereleasewas notobserved.Atthenextstage,themaleclimbedonthefemale (n=14),holdingherwithhisclawsandremainedinthatpositionfor

2.3±1min(range1–4).Sometimes,thefemalesrefusedthemales

formating(n=4),thosewalkedawayfromthemaleand began tofly.

Whenthemalewasacceptedbythefemale(n=10),itplaced itsbodytoreachthefemale’spygidium.Next,rhythmical move-mentsofthemaleabdomenwereobservedwhileitexposedthe aedeagus andbegan the copulation.Copulationlasted on aver-age10.4±4.3min(range5–16).Aftercopulation,themale(n=10)

retractedtheaedeagusin8sandremainedonthefemalean aver-ageof18.0±6min(range10–28);afterwardthemaleclimbedoff

thefemaleandtheyseparatedfromeachother.Femalescopulated inthelaboratoryonlybetween19:00and00:00h;two copula-tionsfrom19:00to20:00h,fourfrom20:00to21:00h,twofrom 21:00to22:00h,onefrom22:00to23:00h,andonefrom23:00to 24:00h.

Adultswerecollectedwithalighttrapfrom18:00to04:00h thenextday(Fig.3).After18:00h,brightnessof1072kJ/m2_began

todecreaseandat20:00h,brightnesswas0kJ/m2_{,coincidingwith}

thebeginningoftheflightactivity.Adultswerecollectedingreater quantityfrom20:00to23:00h.Theaveragetemperatureduringthe flightobservationsrangedfrom32.7◦_Cto21.1◦_{Cbetween18:00}

and06:00h,respectively(Fig.53).

Discussion

ThestepsrelatedtothematingbehaviorofC.melanocephala

aredescribedforthefirsttime.Someinformationisknownabout matingbehaviorofsomeCyclocephalaspecies.Souzaetal.(2014a)

studiedthebiologicalaspectsofC.distinctaBurmeister,1847and

foundthatcopulationoccurredfrom18:00to20:00h.ForC.celata,

Souza et al. (2014b) reported that adults mate day and night.

AdultsofC.verticaliskeptinthelaboratorymatewithan aver-agedurationofabout12–19.2min(BarbosaandRodrigues,2016;

Rodriguesetal.,2010).ForC.lunulata,copulationlasted15–20min,

andthefemalesmaymatemorethanonce(Stechauner-Rohrínger

andPardo-Locarno,2010).

Eventhoughtherewasacontactwiththeantennaeandfirst pairoflegswhenmalesgetclosertofemales,noevidenceof sex-ualpheromonereleasehasbeenobservedforthem.Inadultsof

Exomalaorientalis(Waterhouse,1875)(Rutelinae),Facundoetal.

(1999)foundthatfemalesreleasesexualpheromoneandattract

Female and male n = 23

Leave the soil and fly actively

Land and form a couple

Land and do not form a couple

Male touches the front part of female

Male climbs on female

Female refuses male and detaches Female accepts male for

copulation

Male bends the abdomen and expose edeagous

Copulation starts with introduction of edeagous

Female remains still

Copulation finishes and male retracts edeagous

Male remains on female after copulation

Male and female detach from each other Male touches the back

part of female

23

14

14

10 4

5

9

9

10

10

10

10

10

10

Fig.52.EthogramofmatingbehaviorofCyclocephalamelanocephala(n=23couples)inthelaboratory.

demonstratedthatthenon-acceptanceofCanthoncyanellus cyanel-lusLeConte,1859(Scarabaeinae)femalesbysomemalesformating wasrelatedtodifferencesinsexualmaturityofbothsexes.Such behaviorwasalsoobservedinAnomalatestaceipennisBlanchard, 1851(Rutelinae)byRodriguesetal.(2014).

Aftercopulation,malesofC.melanocephalaremainedonfemales probablytopreventanothermalefromcopulatingwithher.Arakaki

etal.(2004)observedthatincopulationsofDasylepidaishigakiensis

(Niijima&Kinoshita,1927)(Melolonthinae)themaleremainedon

guardoverthefemaleaftercopulationtoavoidtheapproachof othermales.InLiogenysbidenticepsMoser,1919(Melolonthinae), malesremainedfor4honaverageonthefemaleaftercopulation, asaprotectionagainstothermales(Rodriguesetal.,2014).

Conflictsofinterest