A New Cantharid Beetle of the Genus Themus (Coleoptera, Cantharidae) from Ishigaki Island, Southwest Japan

5 Pages·1991·4.3 MB·English

by  Okushima, Y

Ellyt'a,Tokyo,19(2): l95-l99,NovemberI5、1gg
A NewCantharidBeetleof theGenus Themus
(Coleoptera,Cantharidae) fromIshigaki
Island,SouthwestJapan
Ytiichi OKUSHIMA
LaboratoryofEntomology,TokyoUniversityofAgrjcullure,
Tokyo,156Japan
AbSt「act Anewcantharidbeetlebelongingtothesubgenus Hap/ot/1e,nusof the
9enuSThe/11usisdescribedandillustratedfromlshigakiIslando「theRyukyus,south_
westJapan. Itis relatedtoaTaiwanesespecies.
UPtothistime,twospeciesofthegenusThenlusMoTscHuLsKY,l857,havebeen
knownf「OmOkinaWa.ISlando「theRyukyus,Japan(AKIYAMA,1977;NAKANE,l988;
SAT0& ISHIDA,1982),andelevenspecieshavebeenknownfromTaiwan(WITTMER,
1983). However, thegenushasnotbeenrecordedfromtheSakishimaGroupofthe
RyukyuIslands,whichliesbetweenthetwoareas.
Recently,1hadanopportunity toexamineaseriesofspecimensof astrange
ThenulsspeciesfromIshigaki lslandoftheSakishimaGroup. It belongstothesub_
9enuSHai)/ot/1emusWITTMER,1973,hithertounknownfromtheRyukyus,becauseof
theabsenceof longitudinal grooves onantennal segments. Its first specimen was
Collected in 1990 on the ewer of Casta/70り/s,sCS/り,c/ara var. sic old,,. Then,1was
abletoobtainnineadditionalspecimensinl991,allofthemhavingbeencaught at
lightinthecentralareaoflshigaki Islandwithprimeval forest.
Afteracarefulexamination,it becameclear that thisspeciesdidnotagreewith
anyoftheknownmembersofthesubgenusHap1ot/1enuls. Itmustbenewtoscience,
andwill bedescribedinthispaper.
IwishtoexpressmyheartythankstoDr.Shun-lobiUENooftheNationalScience
Museum (Nat. Hist), Tokyo, for hiscritical readingof theoriginalmanuscript, to
ProfessorMasatakaSAToofNagoyaWomen'sUniversity,ProfessorYasuakiWATA-
NABEandDr.ShujiOKAJIMAof TokyoUniversityofAgriculture, for theirkindad-
viceonthepresentstudy,andtoDr.MamoruOwADAoftheNationalScienceMuseum
(Nat.Hist),Tokyo,Mr.TatsuoHANATANlandTakashiFuKA1sHloflshigaki Island,
fortheir kindsupport invariousways.
l96 Yuichi OKUsHIMA
Themus(Hlapl,othemus)ishigakiellsisOKusHIMA,sp nov.
[Japanesename: Ishigaki-ao-joukai]
(Figs.1-5)
Male. Head, pronota1marking, scutellum, 1st and 2ndsegmentsof antennae
andlegsblack;3rdtolithsegmentsofantennae,maxillaryandlabialpalpi,eyes,and
meso-andmetasternadarkbrown; prothoraxyellow;elytrabluewithdullmetallic
luster; abdominal sternitesorange. Bodyrather closelycoveredwithyellowpubes-
cence;apicalmarginofclypeusfringedwithbrownbristles; 1st and2nd segments
ofantennaeandlegscloselycoveredwithdark brownpubescence;3rdto11thseg-
ments of antennae covered withappressedmicro-pubescencesparsely intermingled
with brown pubescence.
Headslightlyshorter thanwidth;discalmost flattenedandweaklydepressedin
lateralareasbeforeeyes;apicalmarginofclypeusarcuatewithitscenter faintlyin-
dented;eyesglobularandstronglyprojected;tipsofmaxillarypalpisomewhatround-
ed;antennaeattainingtoapicalthirdofelytra,1stsegmentclavate,2ndto11thsub-
cylindrical, relativelengthsofantennalsegmentsasfollows: 19:15:10:19:19:20:
19: 19:16.5:15.5: 17.
Pronotumsubquadrate,1.10times(intheholotype; range1.08-1.15)aswideas
head, 0.78(0.76-0.81) timesaslongaswide;anterior andposterior margins feebly
sinuate; lateral margins weakly arcuate; anterior angles obtuse; posterior angles
rounded; discswollen,especiallysoin theposterior area; antero-1atera1areas hol-
lowed;medic-longitudinal furrowdistinct inposterior halfand indistinct in anterior
half; a furrowalong the posterior margindistinct; dorsal black markingextending
fromapex tobase. Scutellum triangular withrounded apex, and closelypunctate.
Apex of presternal process truncated. Mesosternum somewhat convex along the
median line. Relativelengthsofhindtarsalsegmentsasfollows:70:47:36:30:35.
Elytraconjointly122 (1.18-1.24) timesaswideas pronotum, 3.21 (3.13-3.30)
timesaslongaswide,thesidesslightlyconvergentposteriadwithdullypointedapices;
sutureand lateral sideswell defined; disc distinctly, closely and rugosely punctate,
providedwith twovaguecostaeoneachelytron.
Malegenitaliastout; ventral processes of lateral lobes very wide andsturdy;
dorsalplateroundlyprojectedoneachsideanddeeplyemarginateatthecenter (Figs.
2-4).
Lengthofbody:18.5mm (intheholotype; range18.2-18.7); lengthof right hind
tibia:6.15(6.10-6.40)mm.
Female. Bodysomewhat longerandwider than in themale. Antennae a little
shorter than in themale. Pronotum 1.14-1.25timesaswideashead,0.71-0.77times
as longaswide. Elytraconjointly1.19-1.26 timesaswideaspronotum, 3.1()-2.24
timesaslongaswide. Eighthabdominalsternitewithadeepcleft at thecenterand
ashallownotchoneachsideof terminalmargin; discsomewhatswollen beforethe
shallownotchoneachsideofterminalmargin(Fig 5).
NewT11e111usfromIshigakiIsland 97
Fi9.1. The'nus(Hap1ot/1enuls) ishlgakie'Isl'sOKusHIMA,sp nov.,c), fron、Ishigaki Is. of the
Ryukyus. (Scale:5.0mm.)
Lengthofbody:19.6-21.0mm;lengthof righthindtibia:5.70-6.20mm.
Typeseries. Holotype: Mt. 0moto-dake,1shigaki Is.,Ryukyus,20-Ill-1990,
,
Y. 0KusHIMAleg. Allotype: ,Yoshihara,Ishigakils.,Ryukyus,5-III-1991,T.FUKA-
ISHIleg. Paratypes:1 ,Urasoko,IshigakiIs.,Ryukyus,17-III-1991,M. 0wADAleg.;
1 1 ,samedataasfortheholotype,but20-III-1991; l ,samelocalityasforthe
,
holotype,21-III-1991,T. HANATANIleg; l ,samedataas for theallotype,but24-
III-1991;2 ,samedataasfor theholotype,but25一川一1991;1 ,samelocalityas
for theholotype,25-III-1991,T. HANATANlleg.
TheholotypeandallotypewillbepreservedinthecollectionoftheLaboratoryof
Entomology, TokyoUniversityofAgriculture. Theparatypesaredistributed to the
l98 Yuichi OKUsl-llMA
5
Figs 2-5. The,tlus (Hap1ot/1emus) is1/igakiensls OKusHIMA, sp nov., 2-4, malegenitalia (2
ventral view,3, lateral view;4, dorsal view); 5,8thabdominalsternitein female. (Scale
1.0mm)
collectionsoftheNationalScienceMuseum (Nat. Hist), Tokyo, Biological Labora-
tory,NagoyaWomen'sUniversity,andmine.
Di'stributlo,7. Ishigaki Is.(theRyukyus,SouthwestJapan).
Remarks. ThisnewspeciesiscloselyrelatedtoThelnus(Hap/othemus)explanat1-
co11is(Pfc,1917)fromTaiwan,butcaneasilybedistinguished fromthelatterbysome-
whatsmaller body,yellowishcolorationof pronotum, complexdorsal plateofmale
genitalia,andthecharacteristicshapeofterminalmarginofthe8thabdominalsternite
in the female.
NewThe,nusfromIshigaki Island 199
要 約
1: 奥島生K一 石 11島1産キンイロジョウカイ属の 新 種 - -石日! 島で採集されたジョウカイポン科
の新極を, イシガキァオジョウカイ Themus (Hap1othemus) ishigakiensis と命名して記破した. 本
種は,台湾から記載された T. (ff)e:x:planatico11is(PIc)に近縁であるが, いくぶん小型で, 前胸背
板の側縁がf,色く, 雄交尾器の背板は複離な形態を示し, 雌の第8順板の形態が異なることによって
区別できる.
References
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MOTSCHULSKY,V.DE,1857. IncectesduJapon. Etud ent.,Helslngfoirs,6:25-41.
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Konchu,Kokura,35:77-82, pl 9.
PIC,M.,1917. Descriptionsabregeesdiverses. Maex-of.-e,lt.,Moulins,(26):2-24.
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- - 1983. DieFamilieCantharidae(Col)aufTaiwan(2.Tell). Ent.Rev.Japan,38:147-172,
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