The larva of Dythemis maya Calvert, 1906 and a redescription of the larva of D. sterilis Hagen, 1861 with a key to the larvae of the genus (Anisoptera: Libellulidae)

2004·2.8 MB·English

by  Novelo-Gutiérrez, R

Odonatologica33(3):279-289 SeptemberI,2004
Thelarvaof Dythemismaya Calvert, 1906and
aredescriptionof thelarvaof D. sterilis Hagen, 1861
witha key tothelarvaeof thegenus
(Anisoptera: Libellulidae)
R.Novelo-Gutiérrez¹ andE.González-Soriano²
1DepartamentodeEntomologia,Institute)deEcologfa,A.C.,ApartadoPostal63,MX-91070Xalapa,
Veracruz, Mexico - e-mail:[email protected]
2 DepartamentodeZoologfa,InstitutodeBiologfa,UNAM,ApartadoPostal70-153,MX-04510Mexico,
D.F.,Mexico — e-mail:[email protected]
Received September10,2003/RevisedandAcceptedFebruary 16,2004
Thelast instarlarvaofD.maya isdescribed andillustratedforthe firsttime,based on
reared material from Hidalgo,MorelosandMichoacanStates, Mexico. Thelarva ofD.
mayaisthelargestofthegenusandisremarkablydifferentfromotherlarvae,mainlybythe
reduced orwantingdorsalprotuberances,andintheshortlateralspineson theabdomen.A
redescriptionofthelarvaofD.sterilis andsomenotesonotherlarvaeofDythemisarealso
provided,andallspeciesarekeyed.
INTRODUCTION
Dythemis Hagen, 1861isaneotropicalgenuswithsevenspecies(BRIDGES, 1993),six
ofwhichhavebeendescribedintheimmaturestage — D. fugaxHagen, 1861(NEED-
HAM, 1904,non-reared), D. multipunctata Kirby, 1894(DEMARMELS, 1982),D.
nigrescens Calvert, 1899(YOUNG&BAYER, 1979),D.rufinervis (Burmeister, 1839)
(KLOTS, 1932by supposition), D. sterilisHagen, 1861 (GEIJSKES, 1946by suppo-
sition),andD. veloxHagen, 1861 (NEEDHAM&COCKERELL, 1903, non-reared;
NEEDHAM, 1904,non-reared).
Herewe describe thelarva ofDythemis maya Calvert, the only larva of the genus
hithertounknown,basedon materialfromHidalgo, Morelos and MichoacanStates,
Mexico;the description isbasedonlastinstarlarvae andexuviae, oneofthesefroma
recently emerged adult.The larvaofD. sterilisHagen isredescribedbasedonreared
individualsfromVeracruzState,Mexico.GEIJSKES (1946)describedthelarvaofthis
species by supposition basedon non-rearedyoungerindividuals(onespecimen was a
280 R. Novelo-Gutierrez&E.Gonzalez-Soriano
F-2 instar).Forcomparison, wedescribesomefeaturesofD. multipunctata Kirby and
D. nigrescens Calvertnot mentionedintheiroriginal larval descriptions, andprovide
akey toall7species.
DYTHEMISMAYACALVERT
Figures1-9
Material.— 4exuviae(2d,25),6last instarlarvae (9).MEXICO;HidalgoState,Zimapan,Rio
SanFrancisco, 20°34’N, 99°38’W(1650m asl), 18-FV-1996, R.Novelo leg.(Id emerging);Michoacan
State,VillaVictoria,18°45T03”N,103°22’680”W (680masl), 17-V-2002,R. Novelo leg.(19),deposited
atIEXA,Xalapa,Mexico;MorelosState,Ajuchitlan,ArroyoLosIdolos, 18°28’065”N,98°59’546”W(950
masl),8-VH-1996,E.Gonzdlez leg.(79, 1d),depositedatCNIN, UNAM.
DESCRIPTION. — Larvae darkbrown, with acomplex pattern ofobscureand light
bands,spots anddots,poorly setose(Fig. 1).Exuviaelightbrown,colorpatternas in
larvaebutlessevident.
Headalmosttwiceas wideaslong, cephalic lobesrounded,notbulging, withlarge
stoutsetae,occiputalmoststraight, slightlyconcaveatmiddle,postocciputwithadense
bmshoflongsetae;anteriormarginofIronswith arow oflong,delicatesetae,remain-
derofheadglabrous. Antennae7-segmented (Fig.2), thethirdthelongestandthefirst
theshortest; relativesizeofantennomeres: 0.6,0.7, 1.0,0.7,0.9,0.9,0.9;basalhalfof
flagellomeres 3-6darkbrown,apical halfyellowandwith long,delicate,sparse setae,
7 whollydarkbrown.Labmmmostlysmooth,setoseonapical0.25, clypeus quitegla-
brous. Mandibles(Fig. 3) withfourincisorcusps, anadditionalsmallcusp atbase of
ventralcusponrightmandible,molarareawiththreelowbluntcusps(Fig.3a),andtwo
lowbluntcusps(Fig. 3b)onrightandleftmandibles,respectively. Maxilla:Galeolacinia
withseventeeth,threelong slightlyincurvedteethon dorsalmargin,threeshortslightly
incurvedteethon ventralmargin,apical toothlargest; maxillary palplittle shorterthan
galeolacinia, endinginarobustbluntspine.Labium;Prementum-postmentumarticula-
tionreachinganteriormarginofmetastemum;prementumsub-rhomboidal(Fig.4),with
8+4,8+5,8+6,9+4,9+5or9+6long setae(usually 8+4),thetwo orthreecentralsetae
thelongest, lateral margins sinuate, widening to distalmargin, thenabruptly widened
atapical 0.30;a groupof 15-17smallspiniformsetaeonlaterodorsalmiddlethird,4-5
short, stoutspiniform setae onthebaseofpalp articulation; ligula prominent (Fig. 4),
its distalmargin finely serrulated,with 18-20shortsetae,two ofthemattip;labialpalp
(Figs4,5a) with8-11 (usually 10)long setae,6-7minutesetaeandonesetellaonbasal
internalsurface, dorsal margin witharow of 16-18small, stout,spiniform setae,distal
margin with 8-9crenulationsmoderately developed, eachcrenulationfinelyserrulated
and with3-5 stoutspiniform setae oninnersurface(Fig. 5b),external surfaceofpalp
mottled;movablehooklong andslender.
Thorax. — Pronotaldisc yellow, with awide, longitudinal, darkbrownbandon
middlethird (Fig. 1),proepistemum yellowwitharow oflargespiniform setae inter-
mingled withadensebrushoflong setae onanteriormargin,proepimeron darkbrown
Dythemislarvae:somedescriptionsandkey 281
witha densebrush of
long whitesetae on its
ventral margin. Pro-
notum with a row of
spiniform setae on an-
terior margin except
atmiddlethird, lateral
margins widely round-
edwithshortspiniform
setae (Fig. 6) (the in-
sertions ofthese setae
are highly developed
giving a granular as-
pect), posterior margin
mostly smooth except
forsomespiniform se-
tae and long delicate
setae on posterolateral
areas. Synthorax with
a longitudinal, lateral,
wide, darkbrownband
forked distally,remain-
derlightbrown, dense-
ly coveredwithminute
spiniform setae. Legs
long (i. e. when fully
extended,hindlegssur-
passingthetipofabdo-
men), yellow, femora
(distal ring poorly de-
fined) and tibiae each
Figs 1-2. Dythemismaya: (1)last instar larva (leftlegsomitted); — (2)
with three dark rings
rightantenna.
(Fig. 1),arow of spini-
formsetae ondorsalandventralbordersoffemora,andonexternalandinternalborders
oftibiae,distalendsoftibiaewithsingle andbranchedsetae oninternalsurfaces(Fig.
7a); tarsilightbrown,withtworows ofspiniform setaeon ventralmargin,theinternal
row onfore-andhindtarsiwithbranchedsetae,theexternalrow withunbranchedse-
tae (Fig.7b),bothrows onmiddletarsi withbranchedsetae;clawsyellow. Wingpads
lightbrownonbasal0.66,remainderyellowish;anteriorwingpadsreaching basal0.50
ofabdominalsegment6, posterior wingpads reaching posterior margin of6.
Abdomen almosttwiceas longas its maximumwidth,sidesconvex, maximum
widthatsegment6, segments 1-5paleonmiddorsalarea, darkerlaterally, 6-10brown
282 R. Novelo-Gulierrez&E.Gonzalez-Soriano
withacomplexpatternofdarkbrownandyellow spotsanddots;lateralmargins of4-9
witharowofsmallspiniform setae increasinginsizeandnumberposteriorly,ending in
asmallspineon8-9(Fig. 1),0.2and0.4aslongasthemiddorsallengthofitsrespective
segment(dorsallength measuredjust lateralofthedorsal protuberance); dorsalprotu-
berances on3-9assmallacutespines (Fig.8a), very uniforminsizeandheight, thaton
3the smallest;posterior margins oftergites 2-5withsmalldelicatesetaeonmiddorsal
areabecoming spiniformon lateralareas, spiniform setae covering allthesurfaceof
6-10;stemites smooth,exceptposterior margins of7-10whichhave arow of minute
spiniformsetae.Caudalappendages (Fig.9):Epiproctandparaproctspyramidal, sharply
Figs 3-5.Dythemismaya:(3)mandibles;(a)rightmandible,internalview, (b)leftmandible, ventrointemal
view; — (4)prementum; — (5)labialpalp:(a)internalviewoftherightlabialpalp(arrowindicatessetella),
(b) detailofthepalpalcrenulations showingthe fineserrulations onborders,aswell asthe stoutspiniform
setaeoninternalside.
Dythemislarvae:somedescriptionsandkey 283
pointed, withlong, whitesetae ondorsal surfaceandlateralmargins(epiproct), andon
dorsalandventralmargins (paraprocts), spiniform setae onmiddorsalandventral sur-
face(epiproct), andon lateralmargins (paraprocts); cerci digitiform,sharply pointed,
smooth;relativesize: epiproct 1.0,paraprocts0.98, cerci0.65(0.62 infemale);basal
widthofepiproct0.80its dorsallength.
Measurements (in mm). —Totallength(includingcaudalappendages)18-22;abdomen 10.2-13;
hindfemur(dorsalmargin)5.2-5.7;maximumwidthofhead 5.2-5.9;maximumwidthofabdomen5.7-7.1;
epiproct 1.32-1.40, paraproct0.93-1.23,cercus0.68-0.89.
BIOLOGICAL NOTES. — Larvae were collectedata smallpool formeddownstream
ofalowwaterfallinMorelosandMichoacan.InMorelos,two exuviaeandoneteneral
adultwerecollectedattheverticalrocky wallsurrounding thepool. Maleswere seen
perching onbushesandsmalltrees surrounding thepool; aggresive interactionsamong
maleswerecommonly seen.Otherodonatescoexisting atthesite wereE. semicircu-
Figs6-8.DetailsofthemorphologyofDythemislarvae: (6)posterolateralborderofpronotum ofD.maya
showingthestout,longsetae; — (7) details oflegsetaeofD. maya:(a)four-branchedsetaeondistalend
ofprotibia, (b)singleandbranched setaeonventralborderofforetarsus; —(8)profileview ofabdominal
tergites1-10showingdorsalprotuberanceson3-9.
284 R. Novelo-Gutierrez &E.Gonzalez-Soriano
lareSelys, 1876,PerithemisintensaKirby, 1889,andAeshnapsilusCalvert, 1947.In
Hidalgo State, amalewas foundemergingonabush at11;18honaclear, sunny day
atapool situated inasecondary basinofashallowstream.
DYTHEMISSTERILISHAGEN
Figures8b, 10-14
Material. — 1 exuviae(<J), 13lastinstarlarvae(5c5,89),2younginstars (<?).MEXICO;Veracruz
State,Tlapacoyan,Ixtacuaco20°03’21”N, 97°05’30”W (100masl), 10-VII-2002,R.Noveloleg.(8<J,89).
DepositedatIEXA,Xalapa,Mexico.
REDESCRIPTION. — Larvae andexuviae asdescribed forD. maya except; Relative
sizeofantennomeres:0.5,0.6, 1.0,0.8,0.9,0.9,0.9,basal0.33of7thantenomeredark,
remainderyellow.Labium;Prementum-postmentum articulationalmostreachingposte-
riormarginofmesostemum;prementumwith5+3,6+3,6+4or7+3 longsetae(usually
6+3), a groupof 10-12small spiniformsetae onlaterodorsalmiddlethird;labialpalp
with 7-8long setae (usually 8), 7-9basal minutesetae oninternalsurface(no setella
observed), dorsalmargin witharowof13-15small, stoutspiniform setae,distalmar-
gin with 8-9 crenulationsmostofthemobsoleteexcept thedorsal two or threewhich
are moderately developed (Fig. 10),with 3-4stoutspiniform setaeontheinnersideof
each crenulation.
Thorax. — Posteriormarginofpronotumsmoothatmiddlethird,denselycovered
withspiniformsetaeonposterolateralareas(Fig. 11).Legs;Femorawiththreedarkrings,
thebasalring thedarkest. Anteriorwing padsreaching posterior marginofabdominal
segment6, posteriorwingpads reaching basal0.75ofsegment7.
Abdomenlonger thanits widestpart (ratio 1:0.8),lateralmargins ofsegments
2-9witharow ofspiniform setae(minuteon2-3) increasing insizeandnumberposte-
riorly,ending inalarge, strongspineon8-9(Fig. 12),thosespines 0.6and0.9 as long
asthemiddorsallength ofitsrespective segment (dorsal lengthmeasuredjustasideof
thedorsalprotuberance); dorsal protuberances present ontergites 3-9(Fig. 8b), small
andupright on 3-4, strong,acuteand backwardly directedspines on5-9, thoseon7-8
the longest; protuberances with abundantlong setaeon 3-5andstoutspiniform setae
on6-9 (Fig. 13); tergites 3-9, including theirposterior margins, densely coveredwith
smallspiniform setaeexcept atmiddlethirdof3-5; sternites 1-5smooth,6 with some
sparse,spiniform setae,7-9withabundantspiniformsetae including posterior margins;
asmall, dark,oval spottoeach sideofmidlineonsternites3-8; asubapical, lateraltuft
oflong, stiff, reddishbrownsetae oneach sideofstemite9.Caudalappendages (Fig.
14): long reddishbrownsetae on dorsalsurfaceandlateralmargins ofepiproct andon
dorsaland ventral margins ofparaprocts; relativesize: epiproct 1.0, paraprocts0.92,
cerci0.66(0.52 infemale);basalwidthofepiproct0.70its dorsallength.
Measurements (inmm).—Total length(includingcaudalappendages) 12.6-15.6;abdomen 7.3-
9.5;hindfemur(dorsalmargin)4.7-5.0;maximumwidthofhead4.5-4.S;maximum widthofabdomen4.9-
5.8;epiproct1.1-1.2,paraproct 1.0-1.1,cerci0.6-0.7;lengthofdorsalprotuberanceonabdominalsegment6,
Dythemislarvae: somedescriptionsandkey 285
0.3-0.4;on7,0.6;on8,0.6-0.7;on9,0.3-0.4(measured fromtheposteriormarginoftheirrespective tergite
totheapexoftheprotuberance).
BIOLOGICALNOTES. — Larvaewerecollectedattheedgesofasmallopenstream in
standing waterorinslowly flowing muddy-sandy areas. Onemaleemergedincaptiv-
ityon July 11,at07:30h.
DYTHEMISMULTIPUNCTATA KIRBY
Figure8c
Material.— Iexuviae(9,reared),1 lastinstarlarva(9).MEXICO:VeracruzState,“LosTuxtlas”,
EstaciondeBiologlaTropical,LagunaEmilia, 18°34’N, 95°04’W,28-VIII-1985, R.Noveloleg.,deposited
inIEXA,Xalapa,Mexico.
Head. — Relativesize ofantennomeres: 0.5,0.6, 1.0, 0.8,0.7,0.7, 0.7.Labium:
Prementumwith6+3 setae, labialpalp with 7 setae. Abdomen: As described forD.
sterilisexcept: dorsalprotuberances on 3-5smalland upright, thoseon6-9 stoutand
backwardly directed(Fig. 8c); sternites 1-4smooth, 5with somesparse,spiniform se-
tae,6-9withabundantspiniform setaeincluding posteriormargins;asmall, dark,oval
spottoeach sideofmidlineonsternites4-8.Caudalappendages: Relativesize;epiproct
1.0,paraprocts 1.0,cerci0.58;basalwidthofepiproct0.70its dorsallength.
Measurements (inmm). —Totallength(includingcaudalapp.) 18.6;abdomen 11.8;hindfemur
(dorsalmargin)5.0;maximumwidthofhead5.0;maximumwidthofabdomen 5.5;epiproct 1.1,paraproct
1.1,cerci0.6;lengthofdorsalprotuberancesonabdominal segment6,0.3;on7,0.4;on8,0.5;on9,0.2.
DYTHEMISNIGRESCENSCALVERT
Figures8d, 15-16
Material. — 4exuviae(38,19)(reared),4lastinstarlarvae(28,29).MEXICO:MorelosState,Tlaq-
uiltenango,ElAstillero,RibCuautla(850masi),5-II-1983,1,Olivaleg.(19);Ayala,SanJuanAhuehueyo
(1150masl),25-11-1985,R.Noveloleg.(38,19emerged2/5-1II-1985);Tlaltizapan,LasEstacas(980masl),
8-V1I-1987,R. Noveloleg.(28);Xochitepec,RioSabinos(1080masl),5-IV-2002.R. Noveloleg.(19).
Head as describedforD. mayaexcept: Relativesizeofantennomeres: 0.5,0.6,1.0,
0.7,0.9,0.9,0.9,7thantennomere yellow.Labium:Prementalsetae7+2,7+3,7+4,or
8+4 (usually 7+3),palpal setae8-9(usually9).
Thorax. — Anteriorwingpads surpassingposterior marginofabdominalsegment
5, posteriorwing padsreaching posteriormarginof6.
Abdomen.— Themaximumwidthisreached atposterior marginofsegment6
(although YOUNG & BAYER,1979,gavedimensionsforsegment 5, intheirfigure
4itis clearthatsegment 6 isthe widest). Lateral margins of4-9withsmallspiniform
setae intermingledwith smalldelicatesetae,ending inalarge, stoutspine on8-9(Fig.
15),being 0.4and0.8aslong as themiddorsallengthoftheirrespective segment;dor-
salprotuberances as describedforD. sterilisbutthaton3small(Fig. 8d); tergites2-10
asstatedforD. maya; sternites1-6smooth,7-9withminutespiniformsetae,scarce and
286 R. Novelo-Gutierrez&E. Gonzalcz-Soriano
sparseon7, abundanton8-9 mainly onposteriormargins, tuftsoflongsetaeonstemi-
te9 as thosedescribed forD. sterilis exceptyellowishcolored.Relativesizeofcaudal
appendages (Fig. 16): Epiproct 1.0,paraprocts 1.0,cerci0.66;basalwidthofepiproct
0.70itsdorsallength.
Measurements (inmm).—Totallength(includingcaudalapp.) 16.5-18;abdomen9.9-10.4;hind
femur(dorsalmargin)5.1-5.3;maximumwidth ofhead4.9-5.0;maximum widthofabdomen S.7-5.9;epi-
proct 1.2,paraprocts 1.2,cerci0.75-0.8;lengthofdorsalprotuberancesonsegment6,0.4-0.5;on7,0.5-0.6;
on8,0.5-0.6;on9,0.3-0.4.
DISCUSSION
ThelarvaofDythemis mayaisremarkably differentfromotherlarvaeofthegenusby
thefollowing features:body size largest, length oflegs (relative tothebody’s length)
theshortest(eg., whenfullyextended,the tibiaeof hindlegs scarcely reaching thetip
ofanalpyramid), lateralspines on abdominalsegments8-9the shortestinrelationto
thedorsallength of theirrespective segment, dorsalprotuberances ontergites 3-9re-
ducedorabsent.Inthislastrespect,itisinteresting tonotethatspecimens ofD. maya
collectedatHidalgo andMichoacan Statesshow dorsalprotuberances on tergites 3-9
reduced,whilethosefromMorelosStatelackthemcompletelyexceptforthatontergite
Figs9-16.DetailsofthemorphologyofDythemislarvae; (9)caudalappendagesofD.maya. dorsal view,
showingthelongsetaeandthesharplypointedapices; — (10)frontodorsalviewofleftlabialpalpofD.steri-
Us,showingdorsal crenulationsmoderatelydeveloped,andremainder obsolete;—(11)posterolateralborder
ofpronotum ofD.sterilis-, —(12)lateral marginoftergite9ofD.sterilis,showingthe spiniformsetaeand
Dythemislarvae;somedescriptionsandkey 287
3,andalsoontergite9 insomeindividuals.
Someinconsistencesarisebetween GEIJSKES’s (1946) original descriptionof the
larvaof D. sterilisand the redescription presented in this paper,probably due to the
youth ofthe specimens Geijskes used.Themaininconsistency is therelativesize of
antennomeres,whichhestatedas: “11, 13, 18, 16, 19,22,21”, these numbersclearly
indicating that6thantennomere is thelongest. However,inthefourspecies treated in
thepresentpaper, wefoundthe3rd antennomere is thelongest, as inmanyOdonata
larvae,withthelast3antennomeres ofthesamelength. Otherminorinconsistenciesare
relatedtobody dimensions.Likewise,KLOTS (1932) mentionedthat thelarvaofD.
rufinervishas “dorsalhookssharpandslenderonsegments3-9, decreasing insizepos-
teriorly, smallon9”. Wehavenotseenlarvaeofthisspecies butinallotherDythemis
larvae,thereverse istrue: dorsalprotuberances on3-8increaseinsize posteriorly,then
decreaseslightly on9.
BesideshavingallthelarvaeofDythemisknown,itisimportant topointoutthatsome
ofthemwere describedfromnotfully grownlarvaeandnon-rearedindividuals(fugax,
velox),as wellas by supposition (rufinervis)(seeabove). Thus,itremainsas animpor-
tanttasktoredescribesuch speciesbasedonfull-grownlarvaeandrearedindividuals.
Dythemis maya was reportedby GONZALEZ& NOVELO(1996) as aspecies en-
tirelongcaudalspine,dorsalview; - (13)middorsal areaofabdominal tergites8-10ofD.sterilis,showing
thespiniformsetaeonposteriormargins,aswellasthedorsalprotuberancesof7-9;—(14) analpyramidof
D. sterilis.dorsal view; — (15)detail oftheposterolateral largespineontergite9 ofD.nigrescens,dorsal
view; — (16)analpyramidofD.nigrescens,dorsalview.
288 R. Novelo-Gutierrez&E. Gonzalez-Soriano
demictoMexico.However,inrecentyears,ithasalsobeenfoundinTexas, USA(AB-
BOT, 1996).In Mexicoitis commonestinthestatesof thePacificslope (fromSinaloa
toGuerrero) although italsohas beenreported from CentralMexicoandsomestates
oftheGulfslope (GONZALEZ&NOVELO, 1996).
KEY TO THEDYTHEMISLARVAE
(ModifiedfromNeedham etal.,2000)
1 Dorsal protuberancesonabdominal segments3-9well developed(Figs8b-d);prementalsetae7-12(oc-
cassionallysomefugaxwith13setae) 2
—Dorsal protuberanceson abdominal segments 3-9reduced (Fig. 8a) or wanting;premental setae
12-15 maya
2 Lateralspinesonabdominalsegment9equaltoorshorterthanthemiddorsallengthofthis segment... 3
—Lateral spines on abdominalsegment 9 almost 1.3-1.5 times the middorsal length ofthis seg-
ment fugax*
3 Largerspecies, metafemurusuallylongerthan 5mm;palpalsetae8-10 4
—Smallerspecies, metafemurusually5mm orshorter;palpalsetae5-8 5
4 Inlateralviewdorsalmarginofdistal0.5ofdorsalprotuberancesonabdominalsegments6and7slanted
distinctlyupward,that ofprotuberanceonsegment8nearlystraightandparalleltobodyaxis velox*
—Inlateralviewdorsal marginof distal 0.5ofdorsal protuberanceson abdominalsegment 6barely
slantedupward, on segment 7 parallel tobodyaxis, andon segment 8 distinctlycurved downward
(Fig.8d) nigrescens
5 Lateralspinesofabdominalsegment9lessthan0.5middorsallengthofsegment;endemictoGreaterAn-
tilles rufinervis*
— Lateralspinesofabdominalsegment 9morethan0.5middorsallengthofsegment 6
6 Inlateralview dorsalprotuberanceonabdominalsegment 4smalland vertical,thaton7reachingbasal
0,25 ofabdominalsegment8(Fig.8c) multipunctata
—Inlateralviewdorsalprotuberanceonabdominalsegment4largeandcurved totherear, thaton7reach-
ingbasal 0.50ofabdominal segment8(Fig.8b) sterilis
Note:Theasterisk(*)indicatesthatlarvaewereunavailable forexamination.
ACKNOWLEDGEMENTS
WethankTIBURCIOLAEZ-APONTE(Xalapa)fortheelectron microphotographs.Biol. CESAR RO-
JAS-GOMEZmadethefinalcompositionofthefigures.SpecialthanksareduetoDrKENJ.TENNESSEN
(Alabama)forhiscriticismofthefinalmanuscript,andforsomedataonthelarvaofD.fugax.
REFERENCES
ABBOT,J.C., 1996.NewandinterestingrecordsfromTexasandOklahoma.Argia8(4): 14-15.
BRIDGES,C, 1993.Catalogueofthefamily-group,genusgroupandspeciesgroupnamesofthe Odonata
oofftthheeWWoorrlldd..[2ndedn].Bridges,Urbana,IL.
DEMARMELS,J.,1982. Cuatronäyadesnuevasdela familiaLibellulidae (Odonata: Anisoptera).Boln
Enl.venez.(N.S.)2(11):94-101.
GEUSKES,D.C., 1946.ObservationsontheOdonataofTobago,BWI. Trans. R.ent.Soc. Land.97:213-
-235.
GONZÄLEZ-SORIANO,E.&R.NOVELO-GUTIERREZ, 1996.Odonata. In:J.Llorente,A.N.Garcia&
E. Gonzälez,[Eds], Biodiversidad, taxonomiaybiogeografiadeartropodosdeMexico:hacia una