Table Of ContentE、l,t,-a,710k、,o,25(1):135-l46,May15,1997
FourNewSpeciesoftheLathrobzumbrachypterumGroup
(Coleoptera,Staphylinidae) fromtheHokurikuDistrict,Japan
YaSuaki WATANABE
LaboratoryofEntomology,TokyoUniversityofAgriculture,Tokyo,156Japan
Abstract FournewspeciesoftheLat/1,・obium(s.str.)b,achvpte,-umgrouparedo_
" scribedunderthenames .(s.str)slegle1 (s.str)noroense, .(s.sir)sﾍ1,-lraAanle1 a
.
L. (s.str)nabetaniense.Theywereobtainedbysiftingdeadleavesor litterindecjduous
broadleavedforestsonthemountainousareasoftheHokurikuDistrict,CentralJapan.
ThemembersoftheLathrobium(s.str)bt-acilypterumgrouparecharacterizedby
thebodysmallerinsizethanintheLathrobium(s.str)pollensgroup.Uptothepres_
ent, nine species of thegroup have been reported from Japan. Six of them (1.
e) l ''ac 'pfen em denst//n, . suszMlta, . s ﾝ1ngon . 0 1e,-a an fs ﾝfda1 hav bee
.
desc「ibedf「omHonshubySHARP(1889),BERNHAUER(1936),WATANABE(1984, l992)
andHAYASHI(1996),twospecies(L tamotsul,L.sanukiense)fromShikokubyWATA-
NABE(1991,1994)andonespecies(L.onodai)fromtheIslandofShimokoshiki-jima
offsouthwesternKyushubyWATANABE(1996).
ThroughthecourtesyofthelateMr.YoshiharuSuGIE,IshikawaPrefecture,Ihad
an opportunity to examine two interesting species of the Lath;-objum (s. str)
brachypterumgroupobtainedbyhimself fromunderdeadleavesor litter indeciduous
broadleaved forestsonthehillyareaofNabetani inTatsunokuchi-machiof Ishikawa
Prefecture,Japan.A量eracarefulexamination,ithasbecomeclearthatthetwospecies
arenew toscience for reasonsofthesecondarysexual charactersoftheabdominal
sternitesandconfigurationofthemalegenitalorgandifferent fromthoseoftheknown
membersofthespecies-group.Theywillbedescribe(linthepresentpaper,together
withtwoothernewspeciesofthesamegrouppreservedinthecollectionoftheNa_
tiona1 Science Museum (Nat.Hist),Tokyo,andof the LaboratoryofEntomology,
TokyoUniversityofAgriculture.
Beforegoing further,IwouldliketoexpressmysincerethankstoDr.Shun-Ichi
UENo,VisitingProfessoratTokyoUniversityofAgriculture, forhisvaluableadviceon
thepresentstudy.ThanksarealsoduetothelateMr.YoshiharuSuGIEandDr. Ichiji
TOGASHI, IshikawaAgriculturalCollege, fortheirkindnessingivingmetheopportu-
nitytoexaminetheinterestingspecimensusedinthisstudy. Ialsoextendmyhearty
9ratitudetoMr.YasuhikoHAYAsHI,Kawanishi-shi, forthegiftofparatypesofthetwo
speciesL.(s.str)ohkuraiandL.(s.str)ishidai.
136 YasuakiWATANABE
Lathrobium(s.str)sugieiY.WATANABE,sp nov.
(Figs.1,2,6-9)
[Japanesename:Sugie-himekobane-nagahanekakushi]
Body length: 6.9-8.0mm (from front marginof head toanal end); 3.3-3.5mm
(fromfrontmarginofheadtoelytra1apices).
Bodyelongate,subparalle1-sided. Colourbrownishblack to black, moderately
shining,withmouthpartsexcept formandibles, legsandtwoapicalsegmentsofab-
domenyellowishbrown,mandiblesandantennaebrownishred.
Male. Headsubtrapezoidal,gentlynarrowedanteriadandfeeblyelevatedmedi-
ally,somewhat transverse(width/length=1.15), lateral sidesweakly arcuate, frontal
between antennal tubercles transversely flattened and impunctate; surface
area
sparsely,distinctlyandsetiferouslypunctured,thepuncturessomewhatsparserinme-
dianareathaninlateral areas,andcoveredwith inde?nitemicroscopicgroundsculp-
tureonlyvisibleunderhighmagnification;eyesverysmalland at, thelongitudinal
diameterofeacheyeone-fourthaslongaspostocularpart.Antennaeelongate,extend-
ingtothemiddleofpronotumandnotthickenedapicad,withbasaltwosegmentspol-
ished,theremainingsgraduallybecomingopaquetowardstheapicalmostsegment,1st
segment robustandstronglydilatedapica,d,conspicuously longer thanbroad(length/
width=2.50), 2nd constricted at thebase, somewhat longer than broad (length/
width=1.06)butremarkablyshorter(2n(i/1st=0.33)andevidentlynarrower(2nd/1st=
0.78) than1st,3rdsomewhat dilatedapicad,apparently longer thanbroad (length/
width=1.56), distinctlylonger(3rd/2nd=1.40)butslightlynarrower(3rd/2nd=0.96)
than 2nd, 4th to 10thmoreor less moniliform, 4th to 6th equal inboth length and
widthtooneanother,4thalittlelonger thanbroad(length/width=1.33)butslightly
shorter (4th/3rd=0.86)andequalinwidthto3rd,7thalittlelonger thanbroad(length/
width=1.28)butslightlyshorter(7th/6th=0.92)andequal inwidthto6th,8thto10th
equal in both length and width to oneanother, each somewhat longer thanbroad
(length/width=1.25)butslightlyshorter(8th/7th=0.91)andnarrower(8th/7th=0.93)
than7th,apicalmost fusiform,morethantwiceaslongasbroad,evidentlylongerthan
10th(apicalmost/10th=1.80)thoughequalinwidthto10th,subacuminateattheapex.
Pronotum elliptical and convex medially,evidently longer thanbroad (length/
width=1.26) anddistinctly longer (pronotum/head=1.38) thoughequal inwidth to
head, widest behindanterior anglesand feeblynarrowedposteriad inanterior three-
fourthsthoughrather abruptlyso inposterior fourth; lateralsidesalmoststraightat
aboutthemiddlethoughslightlyarcuateinanterior fourthasseenfromdorsalside,an-
teriormarginslightlyemarginateatthemiddle,posteriormargintruncate,anterioran-
glesroundedandinvisiblefromabove,posterioronesnarrowlyrounded;surfacemore
denselyandmoreroughlypuncturedthanonhead,providedwithanarrowlongitudinal
smoothspaceat themiddlethroughthewholelengthofpronotum,andsometimes
bearinganindefinitelongitudinalsulcusalongthemedianlinewithinasmoothspace
at thebasalpart.Scutellumsubtriangular,providedwithafewpuncturesonthesur-
FourNew LathrobiumfromHokuriku 137
.、
'-一一 一ー
.一
、、、Ir'11.1
Fig. 1. Latht'obiuln(s.str)sugie1Y.WATA-
NABE,sp nov., fromNabetani,Tatsu-
,
nokuchi-machi, Ishikawa Prefecture.
Scale: 1.0mm.
face.Elytraoblong,slightlydilatedposteriadandaslongasoronlyjustbroaderthan
long (width/length=1.05), distinctly shorter than (elytra/pronotum=0.72) though
equalinwidthtopronotum;lateralsidesfeeblyarcuate,posteriormarginemarginateat
themiddle,posterioranglesbroadlyrounded;surfacecoveredwithdenser,muchshal-
lower andmuch roughersetiferouspuncturesthanthoseonpronotum. Legsmoder-
atelylong;profemurremarkablythickened,thoughabruptlyconstrictedneartheapex
andexcavatedinapicalhalfontheinnerside,sothattheanteriorpartoftheexcavation
formsasubtriangularblunt tooth;protibiawidenedapicad,hollowedinbasalhalton
theinnermarginandprovidedwithfourorsotransverserowsofcomb-likefinegolden
setaeinbasalhalfwithinthehollow;meso-andmetatibiaesimple; 1stto4thprotarsa1
138 YaSuakiWATANABE
Figs. 2-3. LastabdominalstemitesinmaleofLathrobium(s.str)spp;L.(s.str)sugieisp nov. (2);L
(s.str)notoensespnov,(3).
segmentsstronglywidene meso-andmetatarsi thin.
Abdomenelongate,widestat5thsegment,morestronglynarrowedposteriadthan
anteriad,3rdto6thtergiteseachshallowlyandtransverselydepressedalongthebase;
surfaceofeachtergitemoderatelycloselycoveredwithfinesuperficialpuncturesand
brownishpubescence;8thtergitemoresparselyandmoreminutelypuncturedthanin
theprecedingtergites;allthetergitescoveredwithfinebrownishpubescence;8thster-
nifesemicircularly excisedat themiddleofposteriormarginand longitudinally de-
pressedinfrontoftheexcision;7thsternitealsoslightlyemarginateat themiddleof
posterior margin and longitudinally,thoughmoreshallowly, depressed at themiddle
beforeposteriormargin than in theprecedingsternite; 6thstemiteprovidedwitha
weaklongitudinaldepressionatthemiddleinfrontofposteriormargin.
Genitalorganelongateandslightlyasymmetrical,moderatelysclerotizedexcept
for membranousdorsal sideof median lobe; median lobeapparently broader than
fusedparamereinthemedianpart,andthenabruptlynarrowedinapicalhalf,whichis
lanceolateasseen fromrightlateralside.Fusedparamereveryslenderandmarkedly
longer thanmedianlobe,gentlycurvedtotherightsideandsomewhatconstrictedat
aboutmiddleasseen fromventral side,anddistinctly curved ventradand sharply
pointedatthetipinprofile.
Female. Similar insizeand faciestomale, buteachoneofthe6thto8thab-
dominalstemitesissimple.
Typeseries. Holotype: ,allotype: Nabetani,Tatsunokuchi-machi,Ishikawa
,
Pref.,Honshu,Japan,20-IV-1995,Y.SUGIEleg.Paratypes:all fromthesamelocality
andbycollectorastheholotype; l(;,21-V-1994;3?d 28-V-1994;1?,5-VI-l994;
1d,12-VI-1994; 19,24-VII-1994;19,7-VIII-1994; 19,13-Vm-1994;1d, 16-
VIII-l994;19,21-III-1995; l9,26-III-l995;2 d,10-IV-l995;2ed,15-IV-1995;
FourNew LathrobiumfromHokuriku 139
Fi9S. 4-5. LastabdominalsternitesinmaleofLathrobium(s.str)spp;L.(s.str)shiritakanumsp
nov
(4),andL.(s.str)nabetanlensesp nov.(5). Scale:0.5mm.
9
7
Fi9S. 6-9. MalegenitalorganofL.(s.str)sugielspnov;ventralview(6),lateralview(7),dorsalvjew
(8),andapicalpartofmedianlobefromtherightside(9).Scale:1.0mm(6_8),0.5mm(g).
140 Yasuaki WATANABE
1?, 16_Iv_1995; 1?, 18-IV-1995; 1?, 1?, 21-IV-1995; 1,3, 2 , 22-IV-1995;
,27-IV-1995;13,30-IV-1995;1?,4-V-1995;1?,5-V-1995;1(i2
3 ,2
,
7_v_1995; 19, 10-V-1995; 1d, 2 , 14-V-l995; 23d, 30-V-1995; l 9, 31-V-
,1_VI-1995;5?3,1?,2-VI-1995;1?,7-VI-1995;1(S,9-VI-1995;2
I995;2
,
ll_vI_1gg5; 1(;,11-VII-1995; 1(1 14-VII-1995; 13,20-VII-1995. All thetype
specjmensaredepositedinthecollectionoftheLaboratoryofEntomology,Tokyo
UniversityofAgriculture.
Distribution. Japan(centralHonshu).
Notes. ThepresentnewspeciesresemblesL. ishidai in general appearanceas
wellasinconfigurationofmalegenitalorgan,butdiffersfromthelatterinthefo11ow-
jngpojnts:headandpronotummorecoarselypunctate,7thand8thabdominalsternites
inmaleeachlongitudinallydepressedatthemiddleinfrontofposteriormargin,and
6thstemiteprovidedwithasmalldepressionat themiddlebeforeposteriormargin;
malegenital organwithmedian lobebroader than fusedparamereinmedianpart,
fusedparameresomewhatcurvedtotherightsideinapicalhalfandmuchslenderer
thanthatofL.(s.str)ishidai.
Bionomics. Thetypespecimenswereobtainedfromunderdeadleavesorlitter
inadeciduousbroadleaved forest consistingofQuercusserrata, Q. cripspulaand
amame1lsJapam'cavar.abtusafa.
Etymology. Thespecificepithetofthepresentnewspeciesisdedicatedtothe
lateMr.YoshiharuSUGIE,whocollectedallthetypespecimens.
Lathrobium(s.str)notoenseY.WATANABE,sp nov.
(Figs3,10-17)
[Japanesename:Noto-himekobane-nagahanekakushi]
Body length: 6.7-7.0mm(from frontmarginofheadtoanalend);3.2-3.4mm
(fromfrontmarginofheadtoelytra1apices).
Maleand female. Infaciesandbodysizesimilartotheprecedingspecies,but
djffers from it inthefollowingpoints.Headmorecloselypuncturedin lateralareas
thoughmoreobscurelycoriaceousonthesurfacethanintheprecedingspecies.Prono-
tummoredistinctlyandevenlynarrowedposteriad,providedwith lesscoarsePunc-
turesthanonheadexcept formedianlongitudinal smoothspace.Elytrasomewhat
transverse(width/length=1.20),slightlybroader(elytra/pronotum=1.07) thoughevi-
dentlyshorter(elytra/pronotum=0.71) thanpronotum;surfacecoveredwithslightly
denserpuncturesthan intheprecedingspecies. Inmale,abdomenwith8thstemite
providedwithasimilarexcisionatthemiddleofposteriormargin,thoughthemedian
depressjonbeforeposteriormargin isshallower; 7thstemitemoreshallowly emar-
gjnateat themiddleofposteriormarginandmoreshallowly depressedbeforethe
emarginationthanintheprecedingspecies;6thsternitelackingthedepressionatthe
middleinfrontofposteriormargin,thoughsometimesprovidedwithanobscurede-
pression.
FourNewLath,・obiu"1fromHokuriku 141
10
Figs. 10-l3. Male genital organof L. (s. str) notoense sp nov; from Mt. Horyu-zan, Wajima-shi,
1shikawaPref.1ventralview(10),lateralview(11),dorsalview(12),andapicalpartofmedian1obe
fromtherightside. Scale: l.0mm(10-12),0.5mm(13).
Malegenitalorganalsosimilartothatoftheprecedingspecies,butdiffersfromit
bythe followingdetails:medianlobebroaderthanthatoftheprecedingspeciesinapi-
calhalf,whichisspindle-shapedasseenfromlateralsideandsubangulateattheapex;
fusedparamererelativelybroad,slightlyconstrictednearthemiddle,abruptlycurved
ventradinapicalbaffinprofile.
Typeseries. Holotype: d,allotype: Horyu-zan, SEslope, Wajima-shi, Ishi-
,
kawaPref.,Honshu,Japan,29-V-1985,Y.NlsHIKAwA」eg.Paratypes:2(id,4 9,same
dataasfortheholotype.ThetypespecimensaredepositedinthecollectionoftheNa-
tionalScienceMuseum(Nat.Hist),Tokyo,except for twopairsoftheparatypespre-
servedinthecollectionoftheLaboratoryofEntomology,TokyoUniversityofAgri-
culture.
Furthe, specinlensexamined. l Sogo,0shimizu-machi, Hakui-gun, Ishikawa
,
Prof.,Honshu,Japan,21-II-1990,1.ToclAsH11eg;1d,samelocalityasabove,19-IV-
1996,A.TANAKAleg.
Thesespecimensslightlydiffer fromthetypespecimens inconfigurationofthe
median lobeandthe fusedparamereinthemalegenitalorgan,but thedifferenceis
consideredtobeaninfraspecificvariation.
Distribution. Japan(centralHonshu).
l42 YaSuaki WATANABE
14 15
Figs. 14-l7. MalegenitalorganofL.(s.str)notoensesp nov fromSogo,Hakui-gunIshikawaPref;
ventralview(14),lateralview(15),dorsal view(16),andapicalpartofmedianlobefromtheright
side(17). Scale:1.0mm(14-16),0.5mm(17).
Biono,rues. Thetypespecimenswereobtainedbyexcavatingascreedeposited
atthesideofanarrowstreamatanaltitudeof410m.
Etymology. Thespecificepithet ofthepresent newspecies isderived fromthe
NotePeninsula,onwhichliesthetypelocality“Mt.Horyu-zan”.
Lathrobium(s.str)shiriltakanumY.WATANABE,sp nov.
(Figs 4,l8-21)
[Japanesename:Shiritaka-himekobane-nagahanekakushi]
Body length:8.0-8.1mm(from frontmarginofheadtoanalend);3.6-3.8mm
(fromfrontmarginofheadtoelytralapices).
Male. Again closely resembles L. (s. str) sugie1in general appearanceand
bodysize,butdifferingfromit inconfigurationofmalegenitalorganaswellasinthe
followingpoints:headlesstransverse(width/length=1.09)andlesscoarselypunctured
thaninL.(s.str)sugiei;pronotumlessnarrowedposteriacしlateralsidesfeeblyarcuate
inwholelength,surfaceslightly lesscloselypuncturedthaninL. (s.str)sugieiwith
the exception of the smooth median space; elytra distinctly broader than long
(width/length=1.l9)andslightlybroaderthanpronotum(elytra/pronotum=1.04),sur-
faceslightlymorecoarselypunctured;abdomenmorecoarselypuncturedonthesur-
FourNew Lathrobiun1fromHokuriku 143
faceofeachtergite,8thstemitemoredeeplyexcisedatthemiddleandmorestrongly
depressedin frontoftheexcision,7thstemitealsomoredistinctlydepressedat the
middlebeforeposteriormargin,surfaceofthedepressionalmostglabrous;otherexter_
na1featuressimilartothoseofL.(s.str)sugiei.
AlsosimilartoL.(s.str)ishidaiY.HAYAsHIin faciesandbodysize,butcanbe
distinguished from itby the followingpoints:headslightlymorecloselyandmore
coarselypuncturedonthesurface;pronotumrelativelybroad,asbroadaselytra,more
stronglynarrowedposteriadinposteriorthird,lateralsidesfeeblyarcuateinposterior
half,surfacemorecoarselypuncturedthaninL.(s.str)ishidai;elytramoretransverse
(width/length=1.19), with lateral sides slightly arcuate, more closely and more
coarsely puncturedon thesurface; abdominal tergiteseachmoresparinglycovered
withcoarserpuncturesthaninL.(s.str) ishida1,8thstemitemoredeeplyexcisedat
themiddleofposteriormarginandnarrowly,longitudinallydepressedin frontofthe
excision,7thsterniteslightlyemarginateatthemiddleofposteriormarginandlongitu-
21
19
Figs. 18-21. MalegenitalorganofL.(s.str)shiritakanumsp nov;ventralview(18),lateralview(19),
dorsalview(20),andapicalpartofmedianlobefromtherightside(21). Scale:1.0mm.
l44 Yasuaki WATANABE
dina11ydepressedalongthemedianline,surfaceofthedepressionalmostglabrous.
MalegenitalorgansimilaringeneralappearancetothoseofL.(s.str)sugie1and
L.(s.str)notoense,butdifferent fromtheminthefollowingpoints:muchmoreelon-
gate,medianlobeabruptlynarrowedinapicalthird,stronglycurvedventradintheapi-
calpartwhichisuncinateinprofile; fusedparameremuchlongerthanmedianlobe,
abruptlynarrowedneartheapexwhichissharplypointedasseenfromventralside.
Fema1e. Unknown
Type series. Holotype: ,Mt.Shiritaka, Tsurugi-machi, Nomi-gun, Ishikawa
Pref.,Honshu,Japan,23-IV-1991,K.TANAKAleg.Paratypes:2 d,samedataasfor
theholotype.ThetypespecimensaredepositedinthecollectionoftheLaboratoryof
Entomology,TokyoUniversityofAgriculture.
Distribution. Japan(centralHonshu).
Bionomics. Thetypespecimenswerecollected fromunderrockdebrisat the
roadsidenearthetopofthemountain.
Etymology. Thespecificepithetofthisnewspeciesisderived fromthetypelo-
cality“Mt.Shiritaka-yama”,whichliestotheeastofTsurugi-machiinIshikawaPre-
fecture.
Lathrobium(s.str)nabetantenseY.WATANABE,spnov.
(Figs5,22-24)
[Japanesename:Nabetani-himekobane-nagahanekakushi]
Bodylength:6.5-7.4mm(from frontmarginofhead toanalend);3.5-3.7mm
(fromfrontmarginofheadtoelytra1apices).
ThepresentnewspeciesresemblesL.(s.str)ohkuraiY.HAYAsHIingeneralap-
pearanceandconfigurationofmalegenitalorgan,butdiffersfromitinmalesecondary
sexualcharacterofabdominalstemitesandindetailsofmalegenitalorgan.
Maleand female. Headsubquadrate,slightlytransverse(width/length=1.03),
moresparinglyand lesscoarselypuncturedandcoveredwithmoredistinctground
sculpturethaninL.(s.str)ohkurai.Pronotumnearlyoblong,slightlymoreelongate
(lengthし/width=1.19),lesscoarselypuncturedonthesurfaceexcept forsmoothmedian
longitudinal space. Elytrasubtrapezoida1and somewhatdilatedposteriad, evidently
transverse(width/length=1.13)andsomewhatbroader thanpronotum(elytra/prono-
tum=1.09);surfacemoresparingly and lesscoarsely punctured than in L. (s. str)
ohkurai.AbdomensimilarlypuncturedoneachtergitetothatinL. (s.str)ohkurai; in
male,8thstemitemoreshallowlyemarginateatthemiddleofposteriormarginthanin
L.(s.str)ohkurai,shallowlyandlongitudinallydepressedinfrontoftheemargination,
surfaceofthedepressionsomewhatdenselycoveredwithmoreblackishsetaethanon
theotherparts,7thstemitealsoshallowlyandellipticallydepressedatthemiddlebe-
foreposteriormargin.
Malegenitalorgansclerotizedexcept formembranousdorsalsideofmedianlobe,
median lobe much shorter than fused paramere, gradually narrowed towards the
