The Trechiama (Coleoptera, Trechinae) of the Asahi Mountains and the Adjacent Volcanoes in Northeast Japan

16 Pages·2001·19.3 MB·English

by  Ueno, S-I

Elytra,nokyo,29(2):369-384,November15,2001
TheTrechzama(Coleoptera,Trechinae)oftheAsahiMountainsand
theA(1jacentVolcanoesinNortheastJapan
Shun-lobiUENo
DepartmentofZoology,NationalScienceMuseum(Nat.Hist),
3-23-1Hyakunin-cho,Shinjuku,Tokyo,169-0073Japan
Abstract Alpineand subalpinespecies of the trechine genus Trechiama are
recorded fromthenon-volcanicAsahiMountainsand the twovolcanoesadjacenttothem,
Mt. Gassan and Mt. Ha-yama, innortheasternHonshu,NortheastJapan. All the five
speciesknownareoculateandrelativelydark-co1ourec(cid:4)belongingtothenivalissubgroup
ofthegroupofToreas,threetothenlvalislineage(s.str)andtwotothekurosawailin-
eage.BoththeAsahiMountainsandMt.Gassanharbourtwospeciesofdifferentlineages,
thoughtheyappeartobeecologicallysegregatedontherespectivemountains,whereasMt.
Ha-yamaseemstobeinhabitedbyonlyaspeciesof thentvalis lineage. 0nlyoneof the
fivespecieswaspreviouslydescribe thatis,TbahaiS.UENo,1994ofthenorthwestern
partoftheAsahiMountains.ThenewnamesgivenareTsotorientls,TmontislunaeandT
mentis?omofthenivalislineage,andTyoshihikoiofthekui,osawailineage.
IamgoingtodedicateapapertoYoshihikoKUROSAWAonceagain,tohismemory
thistime.Thesubject tobetakenup isthetrechinebeetlesbelongingto thegenus
Trechiama foundon the Asahi Mountains and thetwovolcanoes a(ljacent to their
northern end. KUROSAWA loved thesemountains fromhisstudent daysat Yamagata
HighSchool,andwillinglyhelpedme toclarifythetrechine faunaof thatpart of
NortheastJapan.
IfirstmetKUROSAWAatOsakanear theendofthe1940s' justaftertheWorldWar
11.HewasverykindtomeandtaughtmemanythingsaboutJapanesebeetles.After
that,healwayshelpedmystudyontheJapaneseCarabidae, forseveralyearsatAizu
whereheresidedthenandatTokyoafter1951.Abouttwodozenyearslater,when I
becamehisonlycolleagueinentomologyattheNationalScienceMuseum,Tokyo,he
receivedmeasagoodfriendandadviser.Wetogetherworkedhardfortheenlargement
and jmprovement of theentomology sectionof our museum for about twenty-five
years,andevenafterhisretirementinthespringof1986,hegavememanyusefulad-
vjceforthedevelopmentofthemuseumandtheJapaneseSocietyofColeOpte(cid:3)ology(cid:5)
Itjsthereforemostregrettablethat Ihavetowritethepresentpaperonlya(cid:2)e(cid:3)his
death. ItwasKUROSAWAwhourgedmetoinvestigatethetrechinefaunaofthehi9h
mountajnsofYamagataPrefecture,andthoughItoldhimabouttheprog(cid:3)eSSofmy(cid:3)e-
searchesfromtimetotime,Iwasunabletofinishmystudiesinhislifetime.Evennow,
therest(cid:1)remajnseveralmattersthathavetobeclarified,butitcansafelybesaidthat
370 Shun-lobiUENo
mypresentknowledge issatisfactorytoshowanoutlineoftheTrechiama faunaof
thesemountains.
TheAsahi Mountainsarearangeofnon-volcanic,mainlygraniticmountainsat
thenorthernpartoftheEchigoRangeandstretchonthebordersofYamagataandNii-
gataPrefectures.Thehighestpointis 0h-asahi-dakelyingat thesouthernpart,which
attainstoaheightof1,870m,but therearemany other peaksthat reachor exceed
1,500minheight.Thoughnotsoconspicuousinelevation,theAsahis lieinaheavy
snowfallareaofnortheasternJapanandhavemanybranchridgessharply carvedby
snowcouloirs.Alpinemeadowsarewelldevelopedonthewatershedabovethetimber-
lineandcontainsnow-patcheshereandthere,someofwhich remain throughout the
yearandfurnishfavourablehabitatsfortrechinebeetles.
AdjacenttothenorthernendoftheAsahis,therearetwovolcanoeseruptedbe-
tweenthegranitebodyoftheAsahisandtheTertiaryformationoftheDewaHills.The
higherofthetwoiscalledGassanandIsl,984minheight.Becauseoftherelatively
gentletopographyathigherelevations,alpinemeadowsaremorewidelydevelopedon
GassanthanontheAsahis,embracinglargesnow-patches,particularlyontheeastern
slope,andyieldingafavourableenvironment forharbouringvariousalpineinsectsin-
clusiveofaTrechiama. 0n theotherhand,theloweroneofthetwovolcanoes, called
Ha-yamaandlyingtotheeastofGassan,ismuchlowerthanthelatter,merelyattain-
ingtoaheightof1,462mandthereforenotexceedingthetimber-limit.Accordingly,
onlyafewsubalpinespeciesareincludedinthecarabid faunaofHa-yama,thougha
Trechiamawasfoundfromcolluviadepositedalonganarrowstreamflowingthrougha
forestofmainlydeciduousbroadleavedtrees.
Inthepresentpaper,thesespeciesofTrechiama,a11oculateand relativelydark-
coloured,willbedealtwith.Theyareextremelysimilartooneanotherinexternalmor-
phology, and cannotbediscriminatedwith confidenceon femalesalone. They are,
however,apparentlyclassifiedintotwolineagesbymarkeddifferenceintheconforma-
tionoftheaedeaga1innerarmature.0neofthemisthemvalislineagewhosecompo-
nentspeciesareratherwidelydistributedonthehighmountainsat thesouthwestern
andsouthernpartsof TohokuDistrict (cf. UENo, 1986, pp. l32-l40, l992, pp.
146-149,1994b,pp 24-28;UENo&0HKAwA,1993).Theotherlineage,thatofT
ku'o'sawa1,hassofarbeenknown fromfourdescribedspecies,ofwhichthreeareen_
demictothehighmountainsatthesouthernpartoftheeuRangestretchingalongthe
axisofTohokuDistrict(UENo,1986,pp.140-142,1989,pp.124-128)andthefourth
wasdescribed fromthenorthwesternpartoftheAsahiMountainsunderthenameT
bahai(UENo,1994a).Wecannowaddafifthspeciestothislineage,arelativeofT
bahaiwhoseoccurrenceonMt.GassanwasalreadynoticedintheNotesfollowjngthe
originaldescriptionofthelatterspecies(UENo, l994a,p.121).
Theabbreviationsusedhereinarethesameasthoseexplainedinpreviouspapers
ofmine.
Beforegoinginto furtherdetails, Iwishtoexpressmyhearty thankstoDr.Ya_
Suaki WATANABE, Dr. Yoshiaki NlsHIKAwA, Mr. Shigeru KIMATA and Mr. Satoru
TrechiamaoftheAsahiMountainsandtheAdjacentVolcanoes 371
MIZuSHIMA fortheir collaborationandhelpinmaking investigationson theremote
mountains and forsupplyingmewithadditional specimensof oneof theGassan
species.
Trechiama(s.str)solorientisS.UENo,sp nov
(Figs.1-2)
Length:5.10-6.00mm(fromapicalmarginofclypeustoapicesofelytra).
CloselysimilartoTnivalisS.UENo(1986,p.132,figs.1-4)andpracticallyin-
distinguishablefromthelatter inexternalmorphology,butconstantlyanddecisively
different fromitintheconfigurationofmalegenitalia,aboveallinthatoftheinnerar-
mature.Considerablyvariableinsize,coloration,standardratiosandotherdetailsin-
cludingthenumberofparameralsetae.Colourusuallydarker thaninT nlvalis,dark
brownwithbrownappendages,sometimeswithblackish forebodyandpitchyblack
elytra.
HeadasinTnlvalisthoughthegenaeareusuallyalittlemoreconvex;eyesvari-
ableinsizeandconvexity,usuallyflatbutsometimesconvexeventhoughsmall;genae
two-thirds tofive-sixthsas longaseyes inmostspecimens,but as longas or even
slightly longerthaneyesinrareexceptions;antennaealsovariableinlength, reaching
basalthree-tenthstothree-seventhsofelytra.PronotumasinTnlvalis,thoughthehind
anglesaremorevariableinthedegreeofsharpnessandprotrusion.Elytraalsosimilar
tothoseofT nlva11s, thoughusually lessparallel-sidedatmiddleandmoreclearly
crenulateinstriae;chaetotaxy identicalwiththatofTnlvalisinbasicpattern. Legs
somewhatshorterthaninTnlvalis.Standardratiosofbodypartsasfollows:PW/HW
1.36-1.48(M I43),PW/PL1.15-1.30(MI21),PW/PA t47-1.62(M I56),PW/PB
1.24-1.52(M I40),PB/PA0.99-1.21(M1.12),EW/PW143-1.60(M I54),EL/EW
1.50-1.60(MI55).
Male genital organ similar in basicconformation to that of T nlvalis, but
markedlydifferentintheconfigurationofaedeagusanditsinnerarmature;theformer
ishigherattheapicalpart,withthedorsalmarginmorestronglyroundedinprofileand
theapexdistinctlytuberculateinbothlateralanddorsalviews; thelatterconsistsof
twoteeth-patchesandasmaller,simplyspatulatecopulatorypiecewhoseapexisrather
widelyrounded.Aedeagusaboutone-thirdaslongaselytra,shortandrobust,some-
whatexpandedventradbehindmiddle,andabruptlynarrowedapicadfrombehindapi-
calorifice,withthedorsalmarginregularlyrounded forthemostpartinlateralview,
morestronglysoattheapicalpart;basalpartlarge,curvedventradbutnotabruptly
bent,andnotregularlyemarginateat thesidesofbasalorifice;sagittalaileron fai(cid:1)ly
large; apjca11obeveryshort,curvedventra andabruptlynarrowedtowardstheex-
tremity,whichisdistinctlytuberculateandbrieflyreflexed;ventralmar9inbisinuatein
lateralview. copulatorypiecelamellar,aboutthree-tenthsaston9asaedea9uS,and
sjmplyspatulate,withtheapexratherwidelyrounded;dorsalteeth-patchlyin9do(cid:1)So-
apicaltocopulatorypieceandsomewhatlongerthanthelatter;leftdorsalteeth-Patch
372 Shun-lobiUENo
1ocatedle(cid:1)dorsaltotheproximalhalfofcopulatorypiece,andobviouslysmallerthan
thedorsalone.Stylesnearlystraight,1eftstyle1ongerthantheright,eachusuallybear-
ing fourorfiveapicalsetae,thoughthenumberofthesetaeoftenincreasestosixon
onestyle,sometimeseventoseven.
variationInelytr,a1chaetotaxy. Ofthe101specimensintotalofthetypeseries,
20(g 12 ),cr t9.8%,aremoreor lessaberrantinthenumberofsetiferousdor-
,
salporesontheelytra.Fourteenofthem(7 7 )arelackinginoneofthedorsal
,
poresonthe3rdstriaononeorbothoftheelytra,andthree femalespossessanextra
(fourth)dorsalporeonthe3rdstriaoftheleftelytron.Eveninnormalspecimenswith
threesetiferousdorsalporesoftheinternalseriesonboththeelytra,themiddleand
posteriordorsalporesareconsiderablyvariableintheirpositiononthe3rdelytra1stria,
andsometimescloselyapproachtoeachother.
Ascomparedwiththeinternalseries,theporeoftheexternalseriesisusuallysta-
ble,but fourspecimens,or3.96%,ofthetypeseriesareaberrant inthisrespect. Two
females fromGingyokusuiarelackinginthisporeontherightelytron,sothat the5th
striaoftherightelytroniscompletelydevoidofsetiferousdorsalporesintheseindi-
viduals. 0ntheotherhan onemalefromthesamelocalitypossessesaseconddorsal
poreonthe5thstriaoftherightelytron,andone female fromKingyokusuihastwo
dorsalporesonthe5thstriaofboththeelytra,averyinterestingexamplesuggestinga
reversionoftheelytra1chaetotaxy.
Typeseries. Holotype: (5, allotype: Gingyokusui, 24-VIII-1994,S. UENo
,
leg. Paratypes: Ie, Gingyokusui, 7-VIII-1983, Y. WATANABE leg; 6 14
, ,
GingyOkuSui,24-VIII-1994,S.UEN0,Y.NSIHIKAwA&Y.WATANABEleg;6 4
, ,
Kingyokusui,25-VIII-1994,S.UENo & Y.NlsHIKAwAleg; 1e,5 Ryumon-zan,
,
25-Vm-1994, S. UENo & Y. NlsHIKAwA leg; 34 28 Minamikanko-zan,
, ,
26-VIII-1994,S.UENo&Y.NISHIKAwAleg.Alldepositedatpresentinthecollection
oftheDepartmentofZoology,NationalScienceMuseum(Nat.Hist),Tokyo.
Localitiesof thetypeseries. GingyokusuionMt. 0h-asahi-dake(typelocal_
itv!),1,630minaltitude,KingyokusuionMt. 0h-asahi-dake,1,670minaltjtude,
Ryumon-zan, 1,570m inaltitude, andMinamikanko-zan, 1,530minaltjtude,all jn
NSihikawa-machiandontheAsahiMountains, inYamagataPrefecture,northeastern
Honshu,NortheastJapan.
Additional specimensexamined. 1 Asahi Mts: Koasahi-dake, 1,530malt,
,
Nishikawa-machi,YamagataPref.,24-VIII-l994,S.UENoleg;1
Asahj Mts: Tori_
ha(cid:2)a-yama,1,410malt.,Asahi-machi,YamagataPref.,24-VIII-1g,g4,s.UENo1eg
(NSMT).
Notes. Thisnewspeciesseemsprimarilyrestrictedtothealpinezoneatthe
SOutheaSte(cid:2)nPartoftheAsahiMountains.Ithassofarbeenknownwithcertaintyfrom
Ofu(cid:2)Stationson theeasternsideofthewatershedridgebetweenOh_asahj_dakeand
Minamikanko-zan,aI1ofwhichlieattheloweredgesofsnow-patchesdevelopedatthe
headsof9u11ieS.Itshouldoccuralsoinotherplaceswithsmi ilarenvironment,though
itmaynotbeeasytolocatefavourablehabitatsofthebeetle.
T1-ec1/ia,IlaoftheAsahiMountainsandtheAdjacentVolcanoes 373
Thetwostations,GingyokusuiandKingyokusui,arelocatedtothenortheastand
northwestofthesummitofMt.0h-asahi-dake, respectively,andtheformerhabitatis
largerandalittlelowerthanthelatter.Abeelinedistancebetweenthetwoisabout700
m.NeartheendofAugust,snow-patchesmelt fromthelowerpartstoanappreciable
extentand feedthestreamsbelow.Gingyokusuiisoneofsuchmeltedsnowsandfur-
nishesatypicalhabitatofthealpineTrechiama,whichisfound frombeneathstones
embeddedattheedgesofthecoldwater.
Theothertwostationsareclosetoeachother,butaremoderatelydistant fromthe
twostationson0h-asahi-dake.0fthese,theRyumon-zansiteliesabout500mnorth-
westofRyumon-zan,abluntheadonthewatershedbranchingoffasideridge,andis
3.8kmdistanttothenorth-northwestinabeelinefromKingyokusui. Thesnow-patch
onthisgentlyslopingplacecompletelymeltedawaywhenwevisiteditonAugust25,
1994,butseveralspecimensoftheTrechiamawerefoundfrombeneathstoneslyingat
thebottomofnarrowgroovesexposedaftertheretreatofthesnow. 0nthecontrary,
theMinamikanko-zansiteisaverysteeplyslantingsnow-patchdevelopedatthenorth-
easternsideofamarkedlynarrowedpartofthewatershedridgeabout600mnorthwest
oftheRyumon-zansite.Thedepressionembracingthesnow-patchlookslikeaminia-
tureofacirque,withasemicircular,gentlyslopingsectionalongtheloweredge.The
trechine beetle was abundant in this narrow humidplace, being found fromunder
heapsofstonesprobablyaccumulatedbythedownwardmovementofthesnowcouloir.
As was recorded above, the two specimens, both females, collected on the
Koasahi Ridgeareexcluded fromthetypeseries, one fromthewesternslopeof
Koasahi_dakeabout1.4kmeast-northeastofGingyokusuiandtheother fromthewest-
ernsideofTorihara-yamaabout2kmeastbysouthofKoasahi-dake.Theirhabitatsare
located inthe forestsofbeechandbirchwellbelow thetimber-limit, henceconsider-
ablydifferentfromthoseofthetypeseriesandsimilartothoseofTbahaiatthenorth-
westernpartoftheAsahiMountainstobedescribedlater.However,theKoasahiRidge
branchesofffromnearthesummitofOh-asahi-dakeandextendstowardstheeast.The
twolocalitiesontheridgearethereforewidelyisolated fromtheknownrangeofT
babaj.SincethelatterspeciesispracticallyindistinguishablefromTso1orlentisinex-
ternalmorphology, it isimpossibletodeterminethetruesystematicstatusof the
Koasahi_dakeandTorihara-yamaspecimensonfemalesalone.However,IPreferto(cid:2)e-
gardthemtentativelyasbelongingtoisolatedpopulationsofTso1orientisinViewof
thegeographicalsituationoftheircollectingsites,leavingthefinalconclusionfo(cid:2)fu-
turejnvestjgations. Incidentally,theTorihara-yamaspecimenislackinginthethi(cid:2)d
dorsalporeonthe3rdstriaoftheleftelytron.
Thjsnewspeciesisnameda(cid:1)ertheAsahiMountains,meaningthemountainsof
therisingsuninJapanese,onwhicharedistributeditshabitats.
374 Shun-IchiUENo
2
(cid:2) /
/ /
//(cid:1)(cid:1)1(cid:1)/
0.5 mm
Figs. 1-2. MalegenitaliaofTrechiama(s.str)so1orientisS.UENo,spnov.,fromGingyokusuionMt.
0h-asahi-dakeoftheAsahiMountains;leftlateralview(1),andapicalpartofaedeagus,dorso-apica1
view(2).
Trechiama(s.str)montislunaeS.UENo,sp nov.
(Figs3-4,7)
Length:5.20-5.65mm(fromapicalmarginofclypeustoapicesofelytra).
Verycloselysimilar inexternalmorphologytoTso1orient1.s,,withalmost identi-
calstandardratios,andpracticallyindistinguishablefromitexceptbytheconstantpe_
culiaritiesofmalegenitalia.ColourusuallyalittlelighterthaninTso1orientls.Head
asinTso1orientls,eyesandantennaesimilarlyvariable.Pronotumandelytraalsosim_
liartothoseofTso1orientis;elytra1striaeusuallymorefaintlycrenulate.LegsasinT
so1orientls.Standard ratios ofbody partsas follows:PW/HW 137-1.50 (M I44),
PW/PL1.16-1.28(MI21),PW/PAt51-1.65(MI57),PW/PB128-1.46(MI41),
PB/PA1.04-1.19(M1.12),EW/PW143-1.55(MI50),EL/EW152-1.60(MI55).
Malegenitalorganmarkedlydifferent inconfiguration fromthatofTnlvaljsbut
similartothelatterinbasicconformation.Aedeagusnearlythree-eighthsaslongas
elyt(cid:1)a,hardlyarcuatebutalmostsemicircularlyroundedatthedorsalmargjnjnlatera1
view,withelongatebasalpartstronglybentventradandrelatively longapjca11obe;
basalorificesmall,withthesidesonlyshallowlyemarginate;sagittalajleronpresent
thou9hSmallandhyaline; viewedlaterally,apical lobegraduallytaperedtowardsthe
ext(cid:1)emity,whichistuberculateandsomewhatreflexed;vieweddorsally,apjca11obe
Somewhatasymmetrical, inclinedtotheright,graduallynarrowedapicad,andnearly
Pointedat thetip;ventralmarginhardlyemarginateinprofile.
Innersacarmed wjth a
T1(cid:5),echla,fiaoftheAsahiMountainsandtheAdjacentVolcanoes 375
4
(cid:2) /
/ /
//(cid:1)(cid:1) /
(cid:3)
0
6
(cid:2) (cid:4)
(cid:2) /
(cid:2)(cid:6)(cid:6) (cid:1)
MalegenitaliaofTrechiama(s.str)spp;leftlateralview(3,5),andapicalpartofaedea9uS,
Fjgs 3_6.
dorso_apical view(4,6). - 3-4.TmontislunaeS.UENo,sp nov., fromMt.Gassan. - 5-6. T
montisf()111S.UENo,spnov fromMt.Ha-yama.
copulatorypieceandanelongatedorsalteeth-patch;copulatorypiecethree-tenthsas
longasaedeagus, lamellar,1anceolate,acicularattheapicalpart,andwithasclero-
tjzedrjbalongtheventralmargin;dorsalteeth-patchhorizontal,consistingofheavily
sclerotjzedteethwhicharecompactandpartially fusedtogether,andobviouslyme(cid:3)e
elongatethancopulatorypieceasawhole.Stylesfairlyslender,leftstyleonlySlightly
longer thantheright,eachusuallybearing fouror fiveapicalsetae, rarelysupple-
mentedbyashortsixthsetaononestyle.
376 Shun-IchiUENo
Fig. 7. (cid:1)''echiama(s.str)montlslunaeS.UENo,sp nov., fromMt.Gassan
,
variationinelytra1chaetotax:y. Ofthetotal20specimensexamined,five(3
,
2 ),or25%,areaberrantinthenumberofsetiferousdorsalporesontheelytra.Two
maleparatypesarelackinginthemiddleporeoftheinternalseriesontherightelytron,
whileonefemalepossessesafourthdorsalporeonthe3rdstriaoftherightelytron.
Tli-echia,naoftheAsahiMountainsandtheAdjacentVolcanoes 377
Onemaleparatypealsopossessesafourthporeontherightelytron,andinthisspeci-
men,asecondporeexistsonthe5thstriaoftheleftelytron.Asecondporeoftheex-
ternal series is also found on the right elytron of a femaleparatype. Thus, two
paratypes( ),or le%of thespecimensexamine showapartial reversionof the
elytralchaetotaxy.
Typeseries. Holotype: ,N(=northernslope)1,630m,1-VIII-1983,S.UENo
leg.Allotype: N I,800m,6-VIII-1964,S.UENo &S.MIzUsHIMA leg.Paratypes:
,
Ie, N I,250m, 5-VIII-1964,S. UENo leg; 4 3 (incl teneraI l , 19), N
,
l,500-1,700m,29-VIII-l963,Y.WATANABE& K.MIzUsAwA leg;2 N I,650m
,
(=Ichi-no-take), 5-VIII-1964, S. UENo & S. MIzUsHIMA leg; 19, N 1,700m,
22-VII-1955, K. MIYAMoRl leg; Ie, 19,N I,900m,6-VIII-l964,S.UENo &S.
MlzUsHIMA leg; 2 , E (=eastern slope) 1,800m, 7-Vm-1964, S. UENo & S.
MlzUsHIMAleg; 2 ,19,WSW(=west-southwesternslope) l,800m,31-VII-1983,
S.UENo&Y.NlsHIKAwAleg.AlldepositedinthecollectionoftheDepartmentofZo-
ology,NationalScienceMuseum(Nat.Hist),Tokyo.
Local(cid:1)os of the type series. Mt. Gassan, 1,250-l,900m in altitude on the
northernslopeand1,800minaltitudeontheeasternslope, inTachikawa-machi,and
l,800minaltitudeonthewest-southwesternslopeinNishikawa-machi,all inYama-
gataPrefectureofnortheasternHonshu,NortheastJapan.
Notes. It seems worthnoting that theaedeagal inner armatureof this new
speciesmorecloselyresemblesthatofTnlva11softheIideMountainsthanthatofT
so1orjentjsoftheAsahiMountains,thoughMt.GassanandtheIidesarewidelysepa-
ratedbytheinterveningAsahis,whichareoccupiedbyTso1orientls. 0ntheother
hanlj,theaedeagusitselfisconsiderablydifferent inconfigurationfromthoseofTn1-
va11sandTso1orientis,whichsuggestsarelativelyisolatedstatusofTmontishlnae.
Thisnewspeciesiswidelydistribute thoughby nomeans abundant, on the
northernslopeofMt.Gassan,whichisrathergentleascomparedwiththesouthern
andparticularlythewesternslopes.Mainlyforclimaticreasons,widealpinemeadows
extenddownwardstonearaheightof1,400monthisslopeandharbourvariousalpine
specjesofjnsects. Tr;echiamamontlslunaeismainly foundabove1,600minaltitude,
thoughoneoftheparatypeswastakeninabirchforestatanelevationof1,250mbe-
lowthetjmber_limit.Ontheeasternandsouthwesternslopes,thisspeciesSeems(cid:2)e-
strjctedtonearthesummit,atanaltitudeofabout1,800m.Atalltheco11eCtin9Sites,
thetrechjnewasfoundfrombeneathstoneslyinginhumidplaces,usuallynotfa(cid:2)f(cid:2)om
snow-patches.
Thenewspecjfjcnameofthistrechinebeetleisderivedfromthenameofthetype
locality,Gassan,whichmeansamoonmountaininJapanese.
Trechiama(s.str)montisf1omS.UEN0,SP nov.
(Figs5-6)
5.05_5.50mm(fromapicalmarginofclypeustoapicesofelyt(cid:2)a)
Length
378 Shun-IchiUENo
VerycloselysimilartoTmontislunaeofMt.Gassanandagreeingwithitinevery
externalcharacterstate,butmarkedlydifferentinmalegenitalic features,aboveall in
thelargesizeanddifferentconfigurationofcopulatorypiece.
Colour reddishbrown,shiny,asinthelight-colouredindividualsofTmontislu-
nae,withlighterpalpiandlegs.HeadasinTmontlslunae,buttheeyesarealwaysflat;
genaegentlyconvex,three-fifthstothree-fourthsaslongaseyes;antennaereaching
basalthree-eighthsofelytrain basalthirdofelytrain Pronotumandelytraasin
, .
Tmontislunae, thelatter alittleshorter andmorewidely depressed in than in
.
LegsalittleslendererthaninTmontlshinae.Standardratiosofbodypartsasfollows:
PW/HW1.38-1.44(MI.41),PW/PL120-1.23(M I22),PW/PA t55-1.61(M I58),
PW/PB143-1.45(M I44),PB/PA1.08-1.12(M1.10),EW/PW147-1.53(M I49),
EL/EW 159-1.67in 1.53 in
, .
Malegenital organsimilar inmanyrespectstothat ofTmontlslunae,but the
aedeagusisalittleshorter,thickerandgentlycompresse abouttwo-fifthsaslongas
elytra,andbearsavery largecopulatorypieceand laterallyextendeddorsal teeth-
patch;copulatorypiecetriangularlyspatulate,about two-fifthsaslongasaedeagus,
aboutaslongasdorsalteeth-patchandpartiallycoveredwithitsleftlateralpart;dorsal
teeth-patch formedbysmallerteethandextendingtotheleftlateralside.Stylesrela-
tivelyshort,eachbearingthreeor fourapicalsetae.
Typeseries. Holotype: ,allotype: , paratype: 1 , 29-VIII-1994, S. UENo
leg.DepositedinthecollectionoftheDepartmentofZoology,NationalScienceMu-
seum(Nat.Hist),Tokyo.
Type locality. Mt.Ha-yama: Yuno-sawa,1,110m inaltitude, inSagae-shj of
YamagataPrefecture,northeasternHonshu,NortheastJapan.
Notes. Thistrechinebeetle issosimilar to T montislunae inboth theexternal
andgenitaliccharacterstatesthat itcouldberegardedasalowaltitudesubspeciesof
thelatter.It isparticularlysimilartolight-colouredindividualsoftheGassanspecjes
occurrin9inthealpinemeadow,butthesmallflateyesanddepigmentationofthebody
oftheHa-yamatrechineareindicativeofitsexistenceinthesubterraneandomajn In
fact,twoofthethreespecimensknownweredugoutfromtheupperhypogeanzone,
andtheremainingonewas found fromanendogeanhabitat. 0n theotherhan
re_
markablemodificationoftheaedeaga1innerarmature,abovealltheremarkablydevel_
oPedCopulatorypiece,seemstosuggestthatthedifferentiationoftheHa_yamatre_
Chineattainstothespecieslevel.Takingalltheseevidencesintoconsideration,Ihave
decidedtoregardtheHa-yamapopulationofTrechiamaasbe1ongjngtoanjndepen_
dentSpecies,notasasubspeciesofTmontislunae,eventhoughthespeciatjonofthem
maybeatasiblingstage.
Mt.Ha-yama,thetypelocalityofthisnewspecies,liesabout16kmtotheeastby
SouthofMt.Gassan.Aswasalreadymentionedintheintroductionofthjspaper,jtjs
muCh1oWe(cid:1)thanthelattervolcanoanddevoidoftruealpinezone.Thethreespecj_
mensofthetypeseriesofTmontlsf0(111werefoundnearthesourceoftheYuno_gawa
ontheWsSter slopeofthemountain,onefrombeneathalargestoneembeddedjnthe