A new species of the bee genus Anthidium (Hymenoptera: Megachilidae) from western North America

5 Pages·1992·1.6 MB·English

Vol. 103,No. 5,November&December, 1992 175
A NEW SPECIES OF THE BEE GENUS
ANTHIDIUM (HYMENOPTERA: MEGACfflLIDAE)
FROM WESTERN NORTH AMERICA
1
RoyR. Snelling2
ABSTRACT: Anthidium cochimi is described from the Lower California peninsula (Baja
CaliforniaSur)andthesouthwesternUnitedStates(Arizona).Structuralfeaturesthatwillaid
initsrecognitionareillustrated.MalesofA.cochimiarerecognizablebyauniquecombination
ofcharacteristicsofmetasomalsternum6andterga6and7;femalesareseparablefromsimilar
species by characteristics of mandibular dentition, labral structure, and the structure of
metasomaltergum6. Diagnosticfeaturesareillustrated.
The followingnewspeciesofAnthidium is one that mayeasilybecon-
fused withA. sonorense Cockerell, particularly since the male shares with
thatspeciesacharacteristichithertobelievedtobeuniquetoA.sonorense
males: the presence ofa short, forward directed spine on the middle of
the apical margin ofmetasomal sternum 6.
Therangesofthetwospeciesappeartobepartiallysympatric.Cockerell
(1923) described/!, sonorense from a male collected in Sonora, Mexico, at
Guaymas. At the same time a female from Isla San Jose in the Gulfof
A
California was described as A. sonorense productum. few years later
Schwarz (1927) described a male from Sacaton, Final Co., Arizona, asA.
A
rohweri. BothA.sonorenseproductum and rohweriweresynonymizedwith
A.sonorensebyGrigarickandStange(1968).Ihavecomparedthetypesofall
three ofthese taxa and agree with the synonymy proposed by Grigarick
and
Stange.
The rangeofA. sonorenseextends from southern Nevada and adjacent
southernCalifornia,throughArizona,southintotheStateofSonora,Mex-
ico, at least to the Guaymas area; it has been collected also on the Lower
California peninsula. There are few records from the peninsula and the
extentofitssouthwarddistributionisunclear.Atpresentthesouthernmost
peninsularrecordisfromsanddunes8kmNofGuerreroNegro,atthebor-
derbetween Baja California and Baja California Sur.
Anthidium cochimi, new species
Figures 1-5
DIAGNOSIS.Male:metasomalsternum6(Fig.2)withsmallanteriorlydirectedmedioapical
spineandlateralridgeslowandevenlyconvex;basalapodemeofsternum8(Fig.3)broadly
1 ReceivedJanuary21, 1992.Accepted March27, 1992.
2EntomologySection,Natural History MuseumofLosAngelesCounty,900Exposition
Boulevard.LosAngeles,California90007.
ENT.NEWS 103(5): 175-179,November& December. 1992
ENTOMOLOGICALNEWS
176
truncate-triangular,apical process shortandbroad; lateral processofmetasomal tergum 6
(Fig. 1) slender and spine-like, slightly curved; lateral lobes oftergum 7 (Fig. 1) roughly
triangular,broad,innermarginsnearlystraight;medianprocessshortandfullyvisibleinpro-
file(notonsameplaneaslaterallobes).Female:mandible(Fig.5)with7teeth;mediangroove
oflabrumbroad,extendingabout2/3labrallengthanditsflankingtuberclesdistinctbutnot
spine-like; median truncationofclypeus(Fig. 5)narrowand nearlystraightapicalmargin
laterad ofmedian truncation with twolow, rounded lobes; preapical carina ofmetasomal
tergum6(Fig.4)minutelycrenulateandoneachsideterminatinginshort,acutetooth,pos-
teriormarginoftergum6visibleonlyinmedian 1/4indorsalview.
DESCRIPTION. Holotypemale,measurements(mm): headwidth(HW)4.4;headlength
(HL)(anteriormarginofclypeustoposteriormarginofvertexinfrontalview)3.5;winglength
(leWnLg)th(forfommemtaarsgoimnao)f1t5e.g3u.lPaa)r8a.t7;ypteosta:lHleWngt3h.2(-T4.L4);(HHLL2+.4d-3o.r4s;aWllLen2g.t4h-3o.f8;mTesLo1s5o.0m-a17.+7.dorsal
Headabout 1.2timesaswideaslong; innereyemargins moderatelyconvergentbelow,
upper interorbital distance 1.1-1.2 times lower interorbital distance; vertex margin nearly
straightinfrontalview,antennalscapeattaininglevelofanteriorocellus;interocellardistance
(IOD) about 1.8 times transverse diameter ofanterior ocellus (OD); ocellocular distance
(OOD) about 1.25 times OD; ocellovertexal distance (OVD) about 1.7 times OD. Clypeus
about1.2timesaslongaswideandseparatedfrominnereyemarginbyabout0.5timesOD;
apicalmargintransverse.Labrumdistinctlyconstrictednearbase;mediangroovedeepand
broad,extendingabout0.66lengthofsegment;flankingtuberclesoflabralgrooveabsentat
base,preapicalpairlowandinconspicuous.
Mesosoma and legs normal for Anthidium, except metatibia outer face anteriorly
carinate.
Metasomaltergum6withpreapicalcarinabroadlyinterruptedinmiddle,endingoneach
sideinspine-like,slightlycurvedprocess;tergum7withbroadlytriangularlaterallobes,inner
marginsnearlystraightformostoftheirlength;medianprocessshort,suberectandcurveddis-
tad,notonsameplaneaslaterallobeswhenviewedinprofile;setalbrushofsternum4brown,
occupyingmiddle0.33ofapicalmargin;apicalmarginofsternum6withshortmedianspine
that is bentcephalad, lateral lobes distinct, lowand evenlyconvex; sternum 8 with basal
apodemebroad,marginsconvergenttowardtransversebase,apicalmarginbroadandlateral
anglesacute,medianprocessshortandbroad.Genitalia:gonostylusinprofilewithmargins
nearlyparallel,apexobliquelytruncate;innerlobeofgonobaseshortandtriangularinventral
view;ventralmarginofpenisvalvewith6-7coarseteeth;apexofpenisvalvestronglynarrowed
andbentventrad.
Punctationofheadandmesosomanormal{orAnthidium,i.e.. mostareascontiguouslyto
subcontiguouslypunctate,puncturesmoderateinsize,discoftegulacontiguouslyandmore
finely punctate; basal area of propodeum distinctly subcontiguously punctate. Discs of
metasomalterga1-3withelevatedmiddleportionmoderatelyandsubcontiguouslypunctate,
interspacesmoderatelyshiny;basaldepressionmorefinelypunctate,puncturesdense;apical
depression more finely and contiguously punctate; elevations ofterga 4-6 more coarsely
punctateexceptinmiddle;tergum7coarselyrugosopunctate.
Colorblackish;antennaandlegsdarkreddish-brownbuttarsimorereddish;clypeus,large
lateralfacemark,endingatlevelofantennalsockets,andundersideofscapepaleyellowish.
Thefollowingbrighteryellow:basal0.66ofouterfaceofmandible;transversespotoneachside
ofvertex;spotonpronotallobe;sublateralbandsonanteriormarginofmesoscutumandspot
orbandadjacenttotegula(maybeabsent);axillarspot(maybeabsent);posteriorbandon
scutellum,narrowlyinterruptedinmiddle;anteriorspotontegula;externalstripeonpro-and
mesotibiae,thatofmesotibiaoften moreorlessbroadlyinterrupted;elongatebasalspoton
metatibia;smallapicalmarkonmetatibia(oftenabsent);externalfaceofallbasitarsi;lateral
andsubmedianmarksofvaryingextentonmetasomalterga 1-5(sometimeslateralandsub-
Vol. 103,No. 5,November& December, 1992 177
median spots narrowly joined on 3-5); tergum 6 with large submedian spots. Tergum 7
immaculate.
Female,measurements(mm): HW3.5-4.3; HL2.7-3.5;WL5.8-7.4;TL9.5-13.2.
Figures 1-5, Anthidium cochimi. 1, male metasomal terga 6-7. dorsal view; 2. male
metasomalsternum6,ventralview;3.malemetasomalsternum8.ventralview.4,female:
metasomal tergum 6,dorsal view; 5,female head, frontal view. FiguresbyTina Ross.
178 ENTOMOLOGICALNEWS
Headwidth1.2-1.3timesheadlength;innereyemarginsmoderatelyconvergentbelow,
upper interoculardistance 1.2-1.3 times lower interocular distance; vertex margin low-
convexinfrontalview,weaklydepressedinmiddle;antennalscapenotattaininglevelof
anteriorocellus;IODabout2timesOD;OODabout2.25timesOD;OVDabout2.5times
OD. Clypeus about 1.3 times as wide as long and separated from inner eye margin by
slightly less than OD; median truncation of apical margin nearly straight, slightly
narrowerthandistancebetweenantennalsockets,apicolateralmarginwithtwolow,con-
vexlobes,labrumaboutasinmalebutwithprominentbasalandpreapicaltuberclesflank-
ingmediangroove. Mandiblewith 7teeth.
Mesosoma and legs as usual in Anthidium. except metatibia outer face anteriorly
carinate.
Transversepreapicalcarinaofmetasomaltergum6(Fig.4)minutelycrenulateandter-
minatingoneachsideasshort,acutetooth;apical marginvisibleindorsalviewonlyin
medianone-fifthbeforepassingundercarina.
PilosityasusualinAnthidium;basitarsiwithdensematsoffinelyplumosehairs;scopa
variablyentirelypaletolargelyverypalebrownishexceptlaterally.
Coloraboutasinmalebutclypeuswithblackapicalmarginandwithbasalblackarea
thatextendsdistadalongmidline,sometimesbeyondmidlength;axillarspotsprominent;
protibialstripeincomplete;mesotibiawithbasalstripeonly;submedianandlateralmarks
ofmetasomaltergum 5sometimesjoined.
TYPEMATERIAL.Holotypemale: 17miSESantaRita,BajaCaliforniaSur,MEXICO,
18Sept. 1983(R.R.Snelling). Paratypes(allfrom BajaCalifornia Sur):4rfcf,499,same
dE1a7sttSaaecapist6hno1Ml9o8it3cyr(pRoe.o;Rn3.drSafncsfe,l"lL1ii1ng9gu9)i;,",S14aN92n,5WA1m9ugkuelms.t(NicnaWe.,4M08uSklemepgLSe,1L9o88re9Ste(opF).t,S.11T49r7Su7exp(atlR.).;R1.918Sc3nf,e(vlRile.i.Rn.Mgi)S;rnae1flll9o,irnvegis)e,,.
onAntigoneleptopus;4<f<f,5mi SanIgnacio,19Sept1983(R.R.Snelling),onTephrosia
tenella;6rfcf,19,RanchoTablon,13kmSGuillermoPrieto,14-18Apr.1983(M.Wasbauer),
3cTcfonprostrateDaleasp.,2cfcT, 1 9exmalaisetrap; 1 9,12miSGuillermoPrieto,7Apr.
1982 (J. Slansky); 1 9, same data except (M.S. Wasbauer); 1 9W, Boca de la Sierra, (near
Miraflores),900ft.elev.,7Mar.1969(R.R.Snelling);299,3.7mi LaBurrera,1400ft.elev.,
7m-i8WOctL.a1B9u7r5re(rRa.,R.1S2n0e0lflti.negl)ev,.o,n8oCcetl.o1s9i7a5fl(oRr.iRb.unSdnael(l1in9g));an1d9,V9e.r6bemsiinNapLaolrmeteor,i(14\ 9S)e;pt1.91,958.35
(R.R. Snelling), on Bebbiajuncea. Holotype and most paratypes in LACM; additional
paratypes deposited in American Museum ofNatural History, California Academy of
Sciences, California Department of Food and Agriculture, and National Museum of
Natural History.
ADDITIONALMATERIAL(Notparatypes).UnitedStates,Arizona:3rfcf.SilverBell
Bajada,PimaCo.,7May 1973(J.L.Neff),onDaleaparryi; 1 cf,sameexcept7June 1973,on
Prosopis;1cf,sameexcept15June1973,onProsopis;499,2.5mi.SWCongress,YavapaiCo.,
3150ftelev., 13 May 1975(R.R. Snelling),onSphaeralcea.
ETYMOLOGY. This species is named for the Cochimi linguistic group of Native
Americanswhoformerly inhabitedcentral LowerCalifornia.
DISCUSSION
Theimportantcharacteristicsofthisspecieshavealreadybeencited
abovein the DIAGNOSIS.Thesealoneshouldbesufficientto separate
A. cochimi from any other known Nearctic species.
Vol. 103,No. 5,November&December, 1992 179
Thespineattheapexofmetasomalsternum6ofthemaleissosimilar
tothatofA.sonorensethatitistemptingtosuggestthatthetwoareclosely
related. On the other hand, there are so many differences in other
characters, e.g., metasomal sculpture, the preapical carina oftergum 6,
the shape of sternum 8, and many details of the genitalia, that this
appearsunlikely.Thefemalesdiffermarkedlyinthestructureofthelab-
rum,thenumberofmandibularteeth,indetailsofmetasomaltergum6,
and in metasomal sculpture.
Becauseofthespotted,ratherthanstriped,metasomaandthecrenu-
latepreapical marginofmetasomaltergum6, femalesofA. cochimimay
be confused with thoseofA. porteraeCockerell, 1900, to which theywill
run in the keyby Schwarz (1927). Females ofA.porterae, however, have
prominentcurved,spine-likelabraltuberclesandthemandiblespossess
only six teeth.
Both sexes ofA. cochimi possess a distinct carina anteriorly on the
outerfaceofthe metatibia,extendingnearlytheentirelength ofthe seg-
ment. A similarcarina is present and sharply defined inA. maculifrons
F. Smith,/!, maculosum Cresson, andA.porterae. Asimilar,but less well
defined, carina is present along approximately the middle one-halfof
the metatibia in A. sonorense. This carina is lacking in the remaining
known North American species o{Anthidium.
Aside from variations in size and in theextentofmaculations,there
is littlevariation in the material I have seen. Males commonly have the
maculations ofthe third to fifth metsomal terga narrowlyjoined along
their posterior margins. In only one female are the lateral and subme-
dian spotsjoined, on the fifth segment only.
ACKNOWLEDGMENTS
FortheloanofrelevanttypematerialIamindebtedtoWojciechPulawski,California
Academy ofSciences,and to Ronald McGinley, National Museum ofNatural History.
Marius Wasbauer loaned material from the collection ofthe California Department of
FoodandAgriculture.AnearlierdraftofthispaperwasreviewedbyTerryGriswoldand
materially improved as a result. My thanks and appreciation to each of these
colleagues.
LITERATURECITED
Cockerell,T.D.A. 1900.ObservationsonbeescollectedatLasVegas.NewMexico,andin
theadjacent mountains.Ann. Mag. Nat. Hist.,(7)5.401-416.
.1923.ExpeditionoftheCaliforniaAcademyofSciencestotheGulfofCalifornia
in 1921.Thebees(1). Proc.Calif.Acad. Sci.,4th series. 12:73-103.
Grigarick,A.A. and L.A. Stange. 1968.Thepollen-collectingbeesoftheAnthidiiniof
California(Hymenoptera: Megachilidae). Bull.Calif. InsectSurv..9:1-113.
Schwarz,H.F.1927.AdditionalNorthAmericanbeesofthegenusAnthidium.Amer.Mus.
Novitates.253:1-17.