Platycheirus urakawensis (Matsumura), a hoverfly new to Europe (Diptera: Syrphidae)
MIKAEL SORENSSON
Introduction
The Diptem family Syrphidae - hoverflies - has attracted much attention lately by Scandinavian entomologists. The Fennoscandian Syrphid fau na is rather rich in species amounting to nearly 400, about 60 of which seem to display a truly boreul. boreo-arctic or arctic distribution patlern.
Species of Pkttyclteirus Lepeletier & Serville
make up about a fou{h of this latter group.
The aphidophagous genus P/44,c/relrirs is one of few Syrphid genera with a pronounced boreal distribution protile in the northern hemisphere
lVocker,'th lqoO). Within the triga zone it is often the dominant genus. The success of P/df,- cftelrrs in northern latitudes can be explained, at least in part, by their dependence on aphids, a primary resource avarLlable td inlinit r? in those areas.
Quite a number of arctic and boreal species of
P L(tj c heirus htrve a very wide distribution within the Palaearctic and Nearctic rcalms. Vockeroth (1990) listed 10 Platycheirus-species from the Nearctic. 23 of which also occur in the Palae- arctic region. Nielsen ( i999) and Bartsch (2001) Iisted 39 PlaD,cheirus-species fiom Sweden and
Sörensson, M.: Plar r-cheirLts ur.lkatteisis (Matsumura.), lr hovelJly new to Europe (Dipte- m: Syrphidae) lPlatlche 'us urakawensis (Matsumura), en blomlluga ny för Europa (Diptera: Syrphidae)l Entomologisk Tidskrift 122 (4). 169-1'72. Lund, Sweden 2001.
ISSN 0013 886x.
The hoverfly PLrtlcreirun- urakawensis (Matsumura), previously known fiom the eastern Palaearctic and North America, is recorded for the fil.st time from Europe and the western Palaearctic. The finding site, a steep roadside rich in llowering plants at 370 400 m on the
hillbp Altarliden in ro hem Sweden, is described and depicted. The site is typical of the boreal laiga with Pice.r abies as the dominating tree species. Chamclers lor sepirsting lemales of P uakawen.sis from P albinanus (F.) are presented and illustrated in a key.
MikaeL Sörcnsson, Zoological Insfihtte, Dept. of Slsten(1tics, Helgonav. 3, SE-22-] 62 Lund. Sweden. E-tnuil: <ntikael.sorenssott@zlx .lLt.se>
Norway, 26 of which, i.e. 2/3 of the Scandinavian launa- extend their distribution into the Nearctic region.
Tentflli\ely l6 oul t)l'Jq Scrndinar ian .pecies may be legarded as borerl. borco-arctic or rrctic (Bartsch 2001, Nielsen 1999), having their main distribution within the taiga belt ard/or arctic zone (5 dso occur in alpine or mountainous zones in Central Eulope). Only three of these (P L.ttimanus Wahlbetg, P nelanopsis Loew, P. kit tilaensis D. & L.) have not been recorded from North America (Vockeroth 1990). This is a clear indication that many trLtly \ortherf. Plut),cheirus- species have a circumpolar distribution, and that probably some other species previously recorded fi'om North America and/or eastern Asia will turn out as Holarctic when studied more intensely. An illustrative example to the latter assumption provides the recent, quite surprising find ofP i.rr- .1&dx,ersls (Matsumura) in norfhem Sweden.
Platy cheirus urakaveasis in Sweden
P urtLktLwensis is a species so 1är recorded fiom the easterl Palaearctic and a few widesplead
169
Mikael Sörenxson
Fig. 1. Leti: Map ol Stnnclitttt,ia ,.itll collectinll site for P. utaLawensis (rcd dot). Right: Collectittg site .lbr P urakargensis on the ntountair AbarLklen, northern Swedetl.
Vijnster: K(1 a övr Skandinavien ned.fl,ntllokalen liir P rakawensis itlritdd (rö.1ptitk). Haiger: Fltldlokaletl Jiit P, urakave sis pri Altculiden t'i.l Rusktrtisk i L),&sele lappntark
Ent. Tidsk 122 (2001)
localities in northern Nofth America. lts center ofdistribution is apparently in the eastern Palae
ctic (Kamchatka, Primorie, the Kurile islands, Chabarovsk, Korea, Japan) wherc it primarily
occurs in high altitudes (Ohara 1980, Mutin &
Barkalov 1999). Öhara (1980) recorded P ,1r'd-
(pwc,.rir abundrnll) from mounlJin regions in Japan, stating that it was the most common spe- cies of the genus. The previously westernn.lost
rccord in the Palaearctic region was Nepal (Vockeroth 1990).
Swedish material of P i.ira,tawersis was first identilied by Hans Bafisch in 2000. One male caught in July 1999 in Swedish Lapland aroused the suspicion of the collector (MS) and it was sent to Bartsch. His identitication was later con- firmed by Tore R. Nielsen.
In total 7 Swedish specimens are known,2
males and 5 females, all from a single locality in southeastern Lapland and caught between the l5th and 25th of July. The fil.St find of a male in July 1999 was more or less accidental. In July 2001 the locality was revisited and 6 further
specimens were sampled, possibly indicating thrl P /,r./&.ir cflrir might not be a ntre species.
The mountain Altarliden, the Swedish collec- ting site ofP urukawensis, is located in northern Sweden, about 30 km north of Lycksele at the south side of rivet Vindelälven (fig. 1). The wide
170
boreal forests of northem Scandinavia constitute the westernmost part of the vast taiga region of northern Palaearclic. The lowland between the coast of the Baltic sea and the Scandinavian morntain chain. about 250 km wide. is charac- terized by an undulating topography mainly coveled by managed coniferous forest. The
terrlin Iise. westwilrd\ toward. the mountain chain, here and there inte[upted by river valleys and minor hills and peaks, the latter usually reaching an altitude of 300-700 meters and
covered by lbrests.
Altarliden rises 492 meters above sea level and dominates its immediate sunoundings. All
captures of P urekawensis were made at 370- 400 meter. lltitude on rr slope by rtt open- u in- ding roadside close to a dense tree margin. The mature, rather wet forest was dominated by spruce (Picea abies), with pine (Plrzus sl/vest- ris),birch (Betula sp.), aspen (Populus tetnula)
and willow (Sal.ix caprea) intermixed. The first specimen of P untkrLvvensis was not noticed in
rhe [ield due to il\ greal resemblrnce lo ils
congener Platycheirus albinanus (.F.), a species
occuring abundantly on the same spot. On the leturn t\ o year\ later smrller. dlrker specimens
ol PLatycheirus were specifically searched fot' by scanning flowels and tlying Sytphids, or by general sweeping of the vegetation.
Ent. Tidskr. 122 (2001 )
Specinrens <tf P urakatran.si.t wete nrainly observcd l-lying rather close to thc -cround. Some were seen visiting llowers such as Rralancrtlas
s p.. G e ru n i u nt st' ! vl i c u nt tnd Ru bu s i tl u a u s, the latter growin-s in lalge, tall patches. Others werc obsclvcd cruising arnong stalks of grass. The habit in genelal did not seem to clivetgc 1't ott't P I Llt \'( lrc i ru s d I b i 111a''1 Lt s.
As lnentioncd lbove P r/z/ialltrl.rl.r occtrrl-cd in ralhcr low nunbers. [t was oulnumbeled by irr elrrse relrrtirt. f.,tl I'iut,trtrr, \\ llicll .,llr.lil c\
!\ir\ \ccl) rn lur;c tttttrthcts lllttrv or te-tin: ott
\(g(tirti,rr. ( )llr.r \f<cics ol P/,/i.r1y'h i/1i. 'lcclll ling simulhneously werc P /r1rl7rr1l1r,r Rondrni.
P yrlogurtus (Zcllersledt), P /xrl4/,/.r (Mcigen)
zrnd P. Llytalus (Meigen).
The biology ol P. urukowut.\is is not known.
Vrckeloth ( 1990) cited JapaDcsc obseNrtions of lrr\irl pr((lirliLrr ,'rr tlre upltid M.\.tt\ I't t.\itttr
(Sulzer). a comlnon pest on vtrious plants.
Recognizing P/alyc h ci rut u rsA( w c n s i s
A\ $ii\ r'ernillkc(l rbovc P itrirÅtrrrirr.ls i' vet)
closc to lhe common aDd wiciesprcad P rilåii'rr-
irirs (F.) rncl cannol with celtainty be distingui- shed in the fleld. Urrder thc rrlicroscolle. how- ever, sevelal clistincl dillerences appear-
Öhrra (1980) carefllly reclcscribed the nrale and female ol P rftrk./1r,.,/rJiJ brsed on Japanesc matcrial, and provided sonre excellent illustra- tions o1'diagnostic chilnctelistics of the rntle.
incJuding head (fr-ontal and Iatcral view), anten- nae, fbrc leg. nlrcLrlitte pattern of abdorlren and genititlia. He also illustrated {llc m culate p!it- tern of the femalc abdomen.
Vockeroth (1990) included P. albirtturtus. P urukdwensi.s. P. scLiLltu.\ (Meigen). P. igrttfc- ,i.)/zrlr.r Kanervo ,ntl P ciliatus Bigot in the
"albimanus sub-vtoup" (2c) undet the inlitmal
"albimanus group". He redescribccl the male of
P. albinqnus and provided diagnostic descrip- tions ()1'1he other species included in the subgro up, also illustratin-q tllc lbre legs.
Males ofall these species arc casily identitied on their charrctcristic conliguration of the 1i)rc legs (t'ig.2), inclutling tarsomcrcs. tibial lbrm.
pubescence and sctltion. Ohara (l9lJ0) antl
Vrckc|oth (1990) give further delails on male chlracteristics.
Itld!\'(hairus ur(tkorcnsi.t tlett ll) EuftP?
Öhara (19E0) and Vockeroth ( 1990) regalcled fenrales ol ll arzrkrrrrtl.r'l.v as insepalable from P albimtuttts.ln the key below the morphological charrctcrs which I have fbuncl mosl r'cliable lbr distinguishing f'erralcs of the species are sum- marized. The key is based on Swedish mate al ol P albinrunus (n=50) with which the tive Swe- dish ftrlales of P r/1r{.rrr?r.sl.r were compaled.
Kcy to females of P. ulbimanus and P. ura- kewensis
L Fcmo|a ot firr-e and lrid-legs yellow. La|gcr. broa der. llaler coloured species- Face Lrsually bronzc or bluish, dull due 1() densc pollinosity. Third rnlenno-
mer-e usually with lar'-9er. distinct orange spot vent ftilly. Postoculu sctae close lo interior ocLllal cor-
ner usually pale. Longest scutcllar-blislles pale.
Lowcr hallof anterior nresopleuror (anepistcmum) slighlly obscured by fine reticuliilion. Hind libia usually yellorv on basll l/J-l/.1. Abdonren broader- spots on tcr,sitcs 2 ,1 larger. silvery. sonrctinrcs widl slight bluish tingc. pollinose spots on T3-.1 largc.
clistinctly quadrlle. (fig. 3a-6r.) Lcrgth: 6.-5-8 mn.
Fenora ol lbrc and nricl legs wilh extensive bhck r-ing coveling mid 2/J's. Snlaller. slender'. clarker' species. Frcc blackish wilh slight bluish tinge.
r{ther shining nredially. dcnsely polliiose only at
sides. Venlral spol on third anlennonlcre vilgue.
snrallcr. darker. Pos()culilr setae pdle with a ft\\' lrlrck selre closcly behind interiol-ocu]rr colner.
LonScst sculellar brislles black. Lower hallofante rio- rnesoplelron brilli{nl. Hind libia black cxccpt
l,'t b \xl l/lU AhLlo rct lr. t',ucr. tcrlite.pot,
snraller. on tergile 2 usually intenscly blue- polli nose spots on Tl zl srnall. vaguely delined. inlerior sides l ne rounded. (fig.3b 6b.) Length:6-7 lnm.
Acknowledgements
Hrns Brrtsch Urst identitied P razrlar|casls. Roy Da nielsson geller'ously rllowcd nrc to stu.ly the collec- lions ol thc Ztxrlogical Museum in Lund, Håktn Ljungber.r ancl Tore R. Niclscn kindly improved the nldnLrscript. All arc hercby greally acknowledgcd- Relerences
Ba|tsch. H. 2001. Swedish ptovincc catalogue [oI ho- verl'lies (Diptera. Syrphitlae). Ent. Tidskr. l2:
(,1):189-215.
Mutin. V A. & A. V. Barkalov. 1999. Key to thc in sects ol Russilur Frr East. Vol. 6. Diptela and Si- phonxpterr. parl l. Dal'nauka. Vlaclivoslok.
17t
Miknel Slircnsson Ent. Tidskr. 122 (2001)
(
h
tr
2^
lmm ]C--->
t/ .a Fig.2-6. Dia|nostic clturactets.for separutiotl ol P albituanus (a)tnd P. urakawensis (b) 2. Male .foreleg.3-6 Fenmle abclonen (3), llind tibia (4), mid fenur (5), anterior ntesopleuron (6).
Fig. 2-6. Diagnostiska karaktärer för besttimninll 4v P- albi anus (4)ocllP utukove sis(b) 2 Ho1ens.from- ben. 3-6. Honans bakkropp (3), bakskenben (41, meltttnlår (5), fränte del av nrcsopleLo?n (6).
Nielsen, T.R. 1999. Checklist and distribution maps
of Norwegian hoverflies, with description of Platyclrcirus Lrskai nov. sp. (Diptera, Syrphidae).
Fagrapport 035. NINA, Trondheim.
öhara, K. 1980. The genus Plarycheirus Lepeletier and Senille, 1828 (Diptera, Syryhidae) of Japan, with descriptions of three new species. Esakia
15.97 -142.
Vockeroth, J. R. 1990. Revision of the Nearctic spe
cies ol Plcttlclrcirus (Diptera, Syrphidae). -
Canadian Entomologlst 122:659--1 66.
Sammantattning
Fynd av blomflugan PLatycheirLts urakawensis (Matsumura) från berget Altarliden norr om
Lycksele i Lycksele lappmark presenteras. Arten
var tidigare närmast känd fi'ån Nepal, med huvudutbredningen förlagd till Ostpalearktis och Nordamerikä. Sannolikt hör den till den bo rcala taigafaunan med många andra arter av lik-
nande vida, stundom cirkumpolät'a utbrednings mönster Altarliden är en av många likartade smärre höjder idet sydlappländska, boreala
skogslandet med dominans av gran och tall samt inslag av björk, asp och sälg. Trots avverkning i sen tid linns på berget fodarande ganska omfat- tande urskogsliknande rester kvar med mycket gamla trädindivider.
Fyndlokalen utgörs av en blomrik vägslänt, fläckvis fuktad av källdng, som gränsal mot ett bryn av mogen granskog belägen på 370-400 m
höjd. Sammanlagt erhölls två hanar och fen]
honor, alla tagna i juli 1999 och 2001, llygande bland grås eller snår av hallon, eller sittande på smörblommor eller midsommarblomster
Afien står nära P. albimnnus (F.) vars honor tidigare inte kunnat skiljas frin P urakawensi.g.
Medan hanar lätt skiljes på bl.a. fiambenens ut seende, se Vockeroth (1990) och fig. 2, utmärkes den mörkare och spensligare honan av P rra-
Åaweirsis främst av svar1fläckiga fram- och mel- lanlår, mera glänsande ansikte, långa svarta sku tellatborst, nästan helsvärta bakskenben, samt dovare färgad bakkropp med mindre puder- lläckirr och rent blå rnetallllickar (fig. .1 6).
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