Description of the larva of Protoneura romanae Meurgey from the West Indies (Zygoptera: Protoneuridae)

2010·0.62 MB·English

by  Meurgey, F

Odonatologica39(2):153-157 June1.2010
Description of thelarva of
ProtoneuraromanaeMeurgey
from theWest Indies
(Zygoptera: Protoneuridae)
F.Meurgey
Museumd’Histoire Naturelle, 12rueVoltaire,F-44000 Nantes,France
[email protected]
ReceivedMarch23, 2009/RevisedandAcceptedDecember 16,2009
The larvafromGuadeloupeisdescribed,illustratedforthefirsttime,andcompared
totheotherdescribed larvae.Additional notesonecologyarealsogiven.
INTRODUCTION
Therecently describedPwtoneuraromanae Meurgey fromGuadeloupe iscur-
rently restrictedto Guadeloupe (FrenchWestIndies) andseemstobepresenton
Montserrat, 70km N of Guadeloupe (DONNELLY,2007). As an uncommon
endemic, thisspecies is in needoffurtherstudies, notably to point outits distri-
butionandecological requirements. TheParcNationaldeGuadeloupe and the
NantesMuseumofNaturalHistoryfinancedathreeweeksmissionin June2007,
whichalloweddescribing larvalhabitatsandto determinetheconservationsta-
tusofP. romanae. Inthe presentpaper, I describeandillustratethefinal larval
instarofP. romanae, basedonspecimens fromGuadeloupe, andgiveadditional
notesontheecology.
PROTONEURA ROMANAE MEURGEY
Figures 1-10
Material. -48 lastinstar larvae (17reared).GUADELOUPE; Basse-Terre,ravine Boudoute,
14-111-2007,F. Meurgeyleg.;Basse-Terre,Sofaia,riviere Sale,F. Meurgeyleg.Allmaterialisdepos-
itedintheNaturalFlistoryMuseum ofNantes (France).
154 F.Meurgey
Figs 1-10.Protoneura romanae, last larval instar: — (1)generalaspect, dorsal view; —(2)premen-
tum, dorsal view;— (3)rightpalpallobe,movable hookomitted,dorsal view; — (4)femalegona-
pophyses, lateral view;cerci omitted; — (5, 7)malegonapophysesand cerci,lateral view; — (6,8)
female gonapophysesand cerci,lateral view; - (9)central lamella,lateral view; - (10)lateral la-
mella,lateral view.
Larva ofProtoneuraromanae 155
DESCRIPTION.-Head. - Trapezoidal,widestateyelevel, largerthanprotho-
rax (Fig. 1).Posteriorlobesprominent, fringedwitharow of 10-12small,strong
setae. Occipitalmargin strongly concave. Prementum(Fig. 2)short, trapezoidal.
Prementum-mentumarticulationreaching theinferiormarginofprocoxae.Mar-
gins sinuatewith 15-20strongsetaeonthedistalhalf.Ligulaprominent, strongly
convexandfinely serrated,uncleft.Prementalsetaeoneoneachside.Labialpalps
eachwith6 setae(rarely 5),movablehooklong, slenderandcurved,longer than
palpal setae (Fig. 3).Distalmarginofpalp withalongsinuousmedialhookand
ashort,almostsquareandfour-toothedlobe(Fig. 4).Antennaeseven segmented,
ringedwithblackandwhiteon antenomeres 2-5, thirdantenomere the longest.
Thorax.-Pronotumquadrangular withablack spotoneachside. Thorax
dark,markedwithfourwhitish spots oneach side.Wing pads parallel, translu-
cent,each witha medianandanapicalblack spot. Innerwing pads reaching the
endofabdominalsegment5. Legs white,eachwiththreedarkbands onfemora
andtibiae, 1 oneach tarsalsegment.
Abdomen.- Cylindrical, brownto yellowish, segments 1-8witheachtwo
black lateralspots andtwo dorsal black spots. Lateralcarinaofsegment 7-10
eachwitharow ofstrongspines, lateralcarinaofsegment6witharow ofsmall
setae, remaindersegmentsbare. Female gonapophyses surpassing distalendof
segment 10, andouterones denticulate(Figs 6,8).Malegonapophyses andcer-
cias inFigures 5 and7. Caudal lamellae(Figs 9, 10)lanceolate, planate except
forthemidrib, andterminallyacute. Laterallamellaeabout sixtimesas long as
wide, withastrong,S-shaped nodusending inansmallspine, locatedat0.80of
itslength. Dorsal carinawithapproximately 20-26setae, ventralcarinawithap-
proximately 40-52setae. Centrallamellaaboutfivetimesaslong asitsmaximum
wide;noduslocatedat0.75ofitslength, triangularandending inanacutespine
oneachside. Dorsalcarinawithapproximately 29-30setae, ventralcarinawith
approx.31-33setae. Basalportionofthelamellaestrongly sclerotized,patterned
withblack transversespots. Distalportion paler, whitishwithadistinctdarkXX-
-shaped mark.
Earlystages donot present thecharacteristic XXblackpattern on caudalla-
mellae.
Measurements (mm;females N=33,malesN= 12).- Total lengthwithoutcaudal lamel-
lae,femalesand males:9.8-10.1;- innerwingpads,females andmales: 3.9-4.0;- abdomen length
withoutcaudal lamellae,femalesand males:6.0-7.2; —central caudallamellae,femalesand males;
4.4-4.S; - lateralcaudal lamellae,females andmales: 4.8-5.0.
DIAGNOSIS. - The larva of Protoneuraromanae is closeto thatof P. ailsa
Donnelly. It differsfromP. ailsaby thefollowing setof criteria:(1) greatersize,
withbody length(including lamellae)comprised between14.6and15.1 mm(11.3
and 12.6in P ailsa); - (2) labialpalpswith6 setae(5 in P. ailsa); - (3)median
lobeoflabialpalpalmost squarebearing fourteeth(truncateandserrulatedinP.
ailsa); - (4) malegonapophyse directeddownward(parallel to the9thsegment
inP.ailsa); - (5)distalendof caudallamellaewitha distinctblack XX-shaped
156 F.Meurgey
mark(always whiteand unspotted in P. ailsa); — (6) nodusof central lamella
triangular inform(trapezoidal in P. ailsa).
Larvaeof P. romanaealso differfromP. capillaris Ramburinhaving 6 palpal
setae (5 in P. capillaris),and by theshape of caudallamellae.
ECOLOGICALNOTES. - Protoneuraromanaeisanuncommonspecies inGuad-
eloupe, observed mainly inforestedareasofBasse-Terreandinfewfloodedfor-
ests onthewestcoastofGrande-Terre.OnBasse-Terre,adultscanbe seenflying
along shadedbanksof montane rivers and streamsbetween 150and700meters
altitude.On Grande-Terre, afew, isolated,smallpopulations werefoundinblood-
wood forests(Pterocarpus officinalis)at sealevel.
Males present astrongterritorialbehaviourconsisting in patrolling a 2-3 m
long territorywith the headturned facing the streambank. Mating takes place
whileinflight untilthetandempair reaches asuitable oviposition site. Thetan-
dem pair skirts the banks, nevermore than 15 cmabovethe water,stopping on
deadfloating debris,like fallenbranches, leafs, or flowerpetals. Theoviposition
begins as soon as the femalechoses a good site. Themale always stays on the
female, beating wings constantly. Eggs are laidin floating deadleavesor small
branches.This can takemorethanhalf anhourtobecompleted.
Larvalhabitatconsistsof calmareas ofmontanerivers andstreamsunderthe
overhanging vegetation. Thetypical habitatconsists ofdeadbranches ofa fast
flowing mountainriver or stream in rain forest, withat least one abrupt bank
colonizedby spikemoss (Selaginella sp.) orferns. Inthesetypes ofhabitats, wa-
terdepth exceeds onemeter andthesubstrate isconstitutedby deadleavesand
rocks. Larvae are foundclinging on lianaor otherplant roots, and sometimes
ontheundersideofleaves.Emergence takes place during the day,between 10:00
a.m.and 16:00p.m. Thelarva climbsonrocks, plants orrootsbutalways inthe
shadiest partofthesupport.Themaximumheight observedwas 5 cm fromthe
water level. Tenerals stay a long timebesidetheirexuviae, aboutonehourand
thenrapidlyfly intothecanopy.
Floodedbloodwoodforest is endangered inthe French WestIndies, dueto a
high anthropogenic pressure andresulting inforestfragmentation. Thelow dis-
persal capability ofP. romanae doesnotallowa good geneticexchange between
distantforests,and weare nowfaceto a highrisk ofextirpation oftheGrande-
-Terre populations.
ACKNOWLEDGEMENTS
Ithank JERRELLJ.DAIGLEand THOMASW.DONNELLY fortheircommentsandsugges-
tions onthe manuscript, andJerrell J.Daigle,GAELLE WEBER and PATRICK JEAN fortheir
helpinthe field.Thisstudywassupportedbythe“ParcNational dela Guadeloupe”,andthe Natu-
ral History MuseumofNantes,France.
Larva ofProtoneura romanae 157
REFERENCES
DONNELLY,T.W.,2007.MoreontheCaribbean Islands; OdonatatakenduringMikeIvie’s Beetle
SurveyonMontserrat.Argia18(4): 13-14.
MEURGEY,F., 2006. Protoneura romanaesp.n.fromGuadeloupe(FrenchWestIndies). Odona-
tologica35(4);369-373.
MEURGEY,F.,2008. DescriptionofthelarvaofProtoneura ailsa Donnelly(Zygoptera:Protoneu-
ridae).Odumtologica37(3):279-282.