The ant-parasitizing genus Pseudacteon Coquillett (Diptera: Phoridae) from China with description of three new species

2013·1.8 MB·

by  Guang-Chun Liu

©EntomologicaFennica.21March2013
The ant-parasitizing genus Pseudacteon Coquillett
(Diptera: Phoridae) from China
with description of three new species
Guang-ChunLiu,Jian-FengWang&Yun-LongCai
Liu, G.-C., Wang, J.-F. & Cai, Y.-L. 2013: The ant-parasitizing genus Pseu-
dacteonCoquillett(Diptera:Phoridae)fromChinawithdescriptionofthreenew
species.—Entomol.Fennica24:53–58.
Theant-parasitizinggenusPseudacteonCoquillettisreportedforthefirsttimein
China.Threenewspecies,P.quadrisetalisLiu&Cai,sp.n.,P.obtusatusLiu&
Cai,sp.n.andP.hexosetalisLiu&Wang,sp.n.,aredescribedandillustrated.
G.-C.Liu,J.-F.Wang,Y.-L.Cai,LiaoningKeyLaboratoryofUrbanIntegrated
PestManagementandEcologicalSecurity,ShenyangUniversity,No.21South
Wanghua Street, Dadong District, Shenyang 110044, China; *Corresponding
author’se-mail:[email protected]
Received16April2012,accepted1November2012
1.Introduction stilllimited.Nospeciesofthegenuswasknown
tooccurinChinapriortothisstudy.Duringthe
ThegenusPseudacteonCoquillettisagroupof surveyoftheparasitizingphoridfliesinthemain-
phoridfliesthatattackandparasitizeants,caus- land China, we found a series of specimens of
ingdecapitationofthehostworkersduringpupa- Pseudacteonspecies.Inthepresentpaper,three
tion.Theseflieshaverecentlyreceivedextensive newspeciesaredescribedandillustrated.
attentionbecauseoftheirpotentialtocontrolin-
troducedfireants(SolenopsisWestwood),which
have caused serious problems in the southern 2.Materialandmethods
UnitedStates,AustraliaandChina(Zhangetal.
2007). Due to intensive studies, at present 65 Thespecimenswerecollectedwithnetsandpre-
Pseudacteonspecieshavebeendescribedworld- servedin75%ethylalcoholinvials.Fromeach
wide,ofwhich52fromtheNeotropicalandNe- specimen, head, legs, wings and abdomen were
arcticRegions.InthePalaearcticRegion,12spe- detached.Theabdomenwasleftin10%KOHfor
cies have been reported, which are covered by severalhoursandthentransferredinglycerinfor
Disney (2000), Disney and Michailovskaya further study. The other body parts were
(2000)andDisneyandWithers(2009).Pseudac- mounded on slide in Belease Fluid (Disney
teonjavensis(Brues)istheonlyspeciesreported 2001).
from the Oriental Region (Brues 1915) and P. The illustrations were made in Leica DM
criniferBeyerisdistributedonlyintheAustralian 2000compoundmicroscopefittedwithadraw-
Region(Beyer1966). ing tube. The photos were taken in Olympus
ChinabelongstothePalaearcticandOriental BX41compoundmicroscopeandSZX10stereo-
Regions and the knowledge of Pseudacteon is zoom microscope with charge-coupled device
54 Liuetal. (cid:127) ENTOMOL.FENNICAVol.24
Fig.1.PseudacteonquadrisetalisLiu&Cai,sp.n.–a.frons.–b.palpus.–c.wing.–d.tergiteVI.–e.sternite
VI.–f.dorsalplates.–g.partofventralplate.Scale:0.1mm.
(CCD)imagingsystem.Theterminologymainly Paratypes:1$,samedataasholotype;2$$,Qiu
followsDisney(2000).Measurementsaregiven Jia Ba (32.92°N, 104.32°E; 2,270 m), Wen
inmillimeters. County,Gansu,7.VIII.2011,CaiYun-Longleg.
ThetypespecimensaredepositedinLiaoning Description. Female. Head. Frons blackish
Key Laboratory of Urban Integrated Pest Man- brown,withabout20hairsplus2onocellartrian-
agementandEcologicalSecurity,ShenyangUni- gleandverydensefinemicrosetae.Fronswith2
versity,Shenyang,China. pairs of supra-antennal bristles, lower pair
proclinate and the upper one reclinate. Upper
pairsareashighastheanterolateralbristles(Fig.
3.Descriptionsofnewspecies 1a).Flagellomere1pear-shapedandaristalight
brown. Palpus pale, very lightly tinged brown,
3.1.PseudacteonquadrisetalisLiu&Cai, and not enlarged, with 4 bristles at apical half
sp.n.(Fig.1) (Fig.1b).
Thorax. Brown with a bare mesopleuron.
Typematerial.Holotype$:China:GuanEGou Eachsideofscutumwithasmallhumericalbris-
(33.92°N, 104.29°E; 2,478 m), Tanchang tle,twonotopleurals,apre-alar,apost-alaranda
County,Gansu.10.VIII.2011,CaiYun-Longleg. pre-scutellardorsocentralbristle.Scutellumwith
ENTOMOL.FENNICAVol.24 (cid:127) ThreenewspeciesofPseudacteon(Phoridae) 55
Fig.2.PseudacteonobtusatusLiu&Cai,sp.n.–a.frons.–b.palpus.–c.wing.–d.tergiteVI.–e.sterniteVI.
–f.ovipersitorsheathinlaterialview.–g.dorsalplate.Scale:0.1mm.
an anterior pair of shorter bristles and a longer ratio 1.96:1. Costal cilia 0.08 mm (Fig. 1c).
posteriorpair.Legsyellowishbrown.Fronttibia Halterebrown.
withoutpalisade.Midtibiawithnear-dorsallon- Abdomen.Tergitesbrownwithminutesparse
gitudinalhairpalisadeextendingabouttwothirds hairs only. Tergites II–V all very much broader
oflengthandcomprising35–40modifiedhairs. thanlong,butprogressivelynarrowingfromter-
Hindfemurwith6–8longhairsbelowbasalhalf giteIIbackwards.TergiteVIvariablewithsome
and 6–8 long anteroventral hairs in outer half. bristles(Fig.1d).Ventergreyishbrownandseg-
Hind tibia with 8–10 differentiated postero- ments 1–5 bare. Sternite VI blackish brown,
dorsals before the stronger pre-apical bristles. clearly defined, with 4 very strong, pin-shaped
The palisade of hind tibia completed, sinuous. bristlesandsomelong,bristle-likehairs(Fig.1e).
Winglength1.68mm.Costalindex0.39.Costal Ovipositor sheath brown, downward. Dorsal
56 Liuetal. (cid:127) ENTOMOL.FENNICAVol.24
platearched,with3–4shorthairsonsub-apexof anteroventralhairsinouterhalf.Hindtibiawith8
eachside(Fig.1f).Ventralplatewith12–16fine, differentiatedposterodorsalsbeforestrongerpre-
long and transverse-inclined hairs arranged in apicalbristles.Winglength1.36mm.Costalin-
twolongitudinalrows(Fig.1g). dex 0.38. Costal ratio 1.87:1. Costal cilia 0.06
Male.Unknown. mm(Fig.2c).Halterebrown.
Etymology.Thenamereferstothecharacters Abdomen.Tergitesbrownwithminutesparse
ofabdominalsterniteVI. hairs only. Tergites II–V all very much broader
Remarks. The new species is easily recog- thanlong,butprogressivelynarrowingfromter-
nizedinhaving4verystrongpin-shapedbristles giteIIbackwards.TergiteVIreducedtoanarrow
onabdominalsterniteVIandtransverse-inclined anteriorstripinmiddlebuteachlateralsidebear-
longhairsonventralplateofovipositorsheath.In ing 2 bristle-like hairs at rear margin (Fig. 2d).
the key to European Pseudacteon (Disney & Venter greyish brown and segments 1–5 bare.
Withers 2009), the species runs to couplet 6, to Sternite VI brown, reduced to a narrow strip in
P.fennicusSchmitz.Itdiffersfromthelatterby4 middle,bearing2shortbristlesand2–3hairson
verystrong,pin-shapedbristlesonsterniteVIand eachill-definedside(Fig.2e).Ovipositorsheath
12–16fine,longandtransverse-inclinedhairson brown,downward(Fig.2f).Dorsalplatewithob-
ventral plate of ovipositor sheath. In the key to tuseprocessonbaseandwithabout10hairson
PseudacteonoftheRussianFarEast(Disney& subapex(Fig.2g).Ventralplatebare.
Michailovskaya 2000), the species runs to cou- Male.Unknown.
plet 4, to the putative female of P. pullum Etymology. The species name refers to the
Michailovskaya,butitisdifferentinhaving35– charactersoftheovipositorsheath.
40modifiedhairsofmidtibialhairpalisade. Remarks.InthekeytoEuropeanPseudacteon
(Disney2009),thespeciesrunstocouplet6,toP.
fennicusSchmitz.Itdiffersfromthelatterinhav-
3.2.PseudacteonobtusatusLiu&Cai,sp.n. inganobtuseprocessondorsalplateofovipositor
(Fig.2) sheath.InthekeytoPseudacteonoftheRussian
Far East (Disney & Michailovskaya 2000), the
Type material. Holotype $: China: Qiu Jia Ba speciesrunstocouplet4,totheputativefemaleof
(32.92°N, 104.32°E; 2,270 m), Wen County, P. pullum Michailovskaya, but it is different in
Gansu, 7.VIII.2011, Cai Yun-Long leg. Paraty- having 18–20 modified hairs of mid tibial hair
pes:3$$,samedataasholotype. palisade.
Description. Female. Head. Fronsyellowish
brown,with20hairsplus2onocellartriangleand 3.3.PseudacteonhexasetalisLiu&Wang,
verydensefinemicrosetae.Fronswith2pairsof
sp.n.(Fig.3)
supra-bristles, lower pair proclinate and upper
onereclinate;upperpairhigherthananterolateral Typematerial.Holotype$:China:Mt.Daming
bristles(Fig.2a).Flagellomere1pear-shapedand (23.28°N, 108.26°E;800m), Guangxi, 10.VIII.
arista light brown, with 4 bristles at apical half. 2011,FengDian-XingandWangJian-Fengleg.
Palpus pale, very lightly tinged brown, and not Description. Female. Head. Fronsyellowish
enlarged(Fig.2b). brown,with20hairsplus2onocellartriangleand
Thorax. Brown with a bare mesopleuron. verydensefinemicrosetae.Fronswith3pairsof
Eachsideofscutumwithasmallhumericalbris- supra-antennal bristles, lower pair is preclinate,
tle,twonotopleurals,apre-alar,apost-alaranda middle and upper ones reclinate; upper pair
pre-scutellardorsocentralbristle.Scutellumwith higherthananterolateralbristles(Fig.3a).Flagel-
an anterior pair of shorter bristles and a longer lomere1pear-shapedandaristalightbrown.Pal-
posterior pair. Legs yellow. Front tibia without puspale,verylightlytingedbrown,andnoten-
palisade.Midtibiawithnear-dorsallongitudinal larged(Fig.3b).
hairpalisadeextendingabouttwothirdsoflength Thorax. Brown, with a bare mesopleuron.
and comprising 18–20 modified hairs. Hind fe- Eachsideofscutumwithasmallhumericalbris-
murwith6longhairsbelowbasalhalfand4long tle,twonotopleurals,apre-alar,apost-alaranda
ENTOMOL.FENNICAVol.24 (cid:127) ThreenewspeciesofPseudacteon(Phoridae) 57
Fig.3.PseudacteonhexasetalisLiu&Wang,sp.n.–a.frons.–b.palpus.–c.wing.–d.tergiteVI.–e.sternite
VI.–f.dorsalplate.–g.ventralplate.Scale:0.1mm.
pre-scutellardorsocentralbristle.Scutellumwith thanlong,butprogressivelynarrowingfromter-
an anterior pair of shorter bristles and a longer giteIIbackwards.TergiteVIwith3–4shortbris-
posterior pair. Legs yellow. Front tibia without tlesoneachside(Fig.3d).Ventergreyishbrown
palisade.Midtibiawithnear-dorsallongitudinal and segments 1–5 bare. Sternite VI blackish
hairpalisadeextendingabouttwothirdsoflength brown, with some weak bristles and hairs (Fig.
and comprising 19 modified hairs. Hind femur 3e). Ovipositor sheath fine, yellowish brown.
with 6 long hairs below basal half and 4 long Dorsalplatewith5shorthairsonsub-apex(Fig.
anteroventralhairsinouterhalf.Hindtibiawith8 3f).Ventralplatepointed,arrow-shaped,middle
differentiatedposterodorsalsbeforethestronger partdark(Fig.3g).
pre-apicalbristles.Winglength1.02mm.Costal Male.Unknown.
index0.36.Costalratio1.44:1.Costalcilia0.05 Etymology. The species name refers to the
mm(Fig.3c).Halterebrown. chaetotaxyoffrons.
Abdomen.Tergitesbrownwithminutesparse Remarks. The new species is easily distin-
hairs only. Tergites II–V all very much broader guishedfromotherspeciesbythreepairsofsu-
58 Liuetal. (cid:127) ENTOMOL.FENNICAVol.24
pra-antennal bristles and the characters of ovi- Disney,R.H.L.2000:RevisionofEuropeanPseudacteon
positorsheath. Coquillett(Diptera,Phoridae).—Bonnerzoologische
Beitraege49:79–91.
Disney,R.H.L.2001:ThepreservationofsmallDiptera.
Acknowledgements. The research was supported by the —Entomologist’sMonthlyMagazine137:155–159.
National Natural Science foundation of China (No. Disney,R.H.L.&Michailovskaya,M.V.2000:Newspe-
31071965). cies of Pseudacteon Coquillett (Diptera: Phoridae)
fromtheFarEastofRussia.—FragmentaFaunistica
43:35–45.
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