Thirteen new Zygoptera larvae from Venezuela (Calopterygidae, Polythoridae, Pseudostigmatidae, Platystictidae, Protoneuridae, Coenagrionidae)

2007·4.6 MB·English

by  De Marmels, J

Odonatologica36(1):27-51 March I.2007
ThirteennewZygopteralarvae
fromVenezuela(Calopterygidae, Polythoridae,
Pseudostigmatidae, Platystictidae,
Protoneuridae, Coenagrionidae)
J.De Marmels
Museo del InstitutedeZoologiaAgricola“Francisco Fernández Yépez”(MIZA),
Facultad deAgronomía,Universidad CentraldeVenezuela,Apartado4579,
Maracay2101-A,Venezuela
[email protected]
ReceivedMarch30,2006 /ReviewedandAcceptedMay24, 2006
Theultimateinstar larvaeorexuviae ofthefollowingspp.andsspp. aredescribed
andillustrated: Hetaerina medinai Racenis,Euthoref.fasciata(Flagen),E.f.plagiata
Selys, E.f.fastigiata(Selys),MicrostigmarotundatumSelys, Palaemnema clementiaSe-
lys,Epipleoneurametallica Racenis,NeoneurafulvicollisSelys, Acanthagrionimeriense
De Marmels,A. vidua Selys, ArgiaadamsiCalvert,Cyanallagmalaterale(Selys), and
C. tamaenseDe Marmels. Akey totheknownlarvaeofPolythoridaefoundin Ven-
ezuela isincluded. Thelarva ofeach sp./ssp. isdiagnosedagainstsimilar larvae of
othertaxa,and notesonthelarval habitatareadded.
INTROCUCTION
Thelarvaeofnumerous species ofZygoptera, mostly rearedorrecovered to-
getherwiththeemerging adult, haveaccumulatedinthecollectionoftheMuseo
delInstitute de Zoologia Agricola “Francisco FernandezYepez” (MIZA) over
thepast twenty years.Inorderto makethis informationavailabletootherwork-
ers, I decidedto describeandillustratetheseimmaturestagesandto offerdiag-
nosticcomments andinformation aboutgeographic distributionandhabitatof
thespecies studied.
28 J.De Marmels
MATERIALANDMETHODS
Alllarvae andsomeexuviaearekeptinalcohol;therestoftheexuviaearekeptdryandweresoaked
with waterforstudy, andlateragaindried andmounted,orintroduced inalcohol and storedinvials.
ThedrawingsweremadeusingastereoscopeWildM8,coupledwith acameralucida. Allmeasure-
ments aregiveninmillimeters. Totallengthdoes notinclude caudal gills;lengthoffemur excludes
trochanter.
Figs1-7.Hetaerinamedinai,ultimateinstarmalelarvafromWaikinima;(1)headand pronotum,dor-
sal view;— (2)prementum,ventralview; — (3)anterior portionofprementum, dorsal view; —(4)
abdominal segments 6-10,left lateral view; - (5)abdominal segments7-10with cerci,dorsal view;
— (6)left lateral gill,left lateralview; - (7)median gill,left lateral view.
ZygopteralarvaefromVenezuela 29
CALOPTERYGIDAE
HETAERINA MEDINAIRÁCENIS, 1968
Figures 1-7
Material (2 3,ultimateinstarlarvae;supposition:onlyspeciesinrangeatthiselevation above
sealevel), - 1 <?,Venezuela,Bolivar State,Waikinima Tepui(CerroGuaiquinimaNational Mon-
ument), 1000 m,05°53’N, 63°30’W,12-11-1990; 1 S,Bolivar State,ElPilon,road Santa Elena de
Uairen-Icabaru,950m,28-1-1985,both J.De Marmelsleg.
Larvaebrown. Iftherewas any body patterninthe living specimens, this has
vanisheddueto thealcohol.Headlittlebroaderthanthorax; occipital lobesob-
tuselyangled withdorsaltubercle.Antennawith sevensegments;length offirst
segmentequaling 80%ofmaximumwidthofhead(Fig.l),pale brownwithba-
salhalfdarkerandextreme tip paler; segmentstwoandthreeshowasimilarpat-
tern. Labiumreaching tobetweensecondpair ofcoxae, otherwiseas illustrated
(Figs 2-3).Pronotumbearing a triangular process oneach sideof middlelobe
directedlaterodorsad(Fig. 1).Femoraandtibiaeofalllegswiththreedarkcross-
bands; there are no strongsetae or spines along anteriorborder offirst femur.
Wingsheathsreaching toendofabdominalsegment4,orbeyond. Abdomenwith
recognizable, albeitvery low, mediodorsaltuberclenearposterior borderofseg-
ments 6-9in thelarva fromWaikinima (Fig. 4;absent inthe specimen from El
Pilon); segment 10withbluntdorsal longitudinal ridge ending inthree closely-
setspines, whichsurpassend of segment;anadditionalspine eachside atsome
distancefromthemedianspines; fourapicalspines laterally oneachside(Figs4-
5);ventrally onelarge spineeachside atabout halfthedistancebetweenmedian
lineandlateral margin, accompanied once by three minuteaccessory spinules;
segments8and 9with lateralapical spine. Caudal gillsas illustrated(Figs 6-7);
allmarginal spinules besetwithasingle, short, soft, apical seta.
Measurem ents (inmm). - Totallength21-24;lateralgill6-7;head width3.0-3.5;hind fe-
mur5,8;hind tibia 5.7-6.2.
REMARKS. — H. medinaiis anendemic ofthe Pantepui region, andwas the
soleHetaerinaspecies present atthecollectingplacesof thelarvae. Theonlysite
known to mewhereH. medinaidescendstobelow500m abovesealevelisat the
bauxiteminesof Los Pijiguaos, innorthwesternBolivar State. There itoccurs
syntopically withH.sanguineaSelysandH. westfalliRacems,bothwithunknown
larvae.Thelarva ofH.medinaidiffers fromthatof H. caiadominulaHagen de-
scribed by GEIJSKES (1943) mainly intheshapeofthecaudalgills.ZLOTY et
al.(1993) describedthelarvaeof sevenspeciesofHetaerinafoundinCostaRica,
fiveofwhichoccurin Venezuelaas well, butoutsidetherange ofH. medinai.
30 J.De Marmels
POLYTHORIDAE
Larvaeofthisfamilyaredifficultandsometimesseemingly impossible to iden-
tifyon external morphology, even at the generic level. The immaturestages of
Figs8-21. DiagnosticcharactersofVenezuelan Polythoridaelarvae:(8-11)head showingangulation
ofoccipitallobes,dorsal view, of(8)Chalcothore montgomeryi,— (9)Chalcopteryx scintillans, —
(10 Coracyane, —(11)Euthoref.fastigiata;- (12-15)shapeofprementumof(12 Coramarina, —
(13)C. cyme, - (14)Euthoref.fastigiata,- (15)E.ffasciata; (16-21)lefthindwingsheath,left
lateralview, of(16) C.marina, -(17)C. cyane,- (18)E. f.fasciata,- (19)E.fasciataplagiata, -
(20)E.f.fastigiata,- (21)E.fastigiatameridana.
Zygopteralarvae fromVenezuela 31
manyspecies are stillunknown, andthe descriptions ofthoseknown arebased
ononeor fewspecimens, afactwhichfurthercomplicates thetask, becausepo-
tentially informative characters cannot be evaluatedby comparison among a
significant numberof taxa, oreven among specimens ofthe same species. Of
thefourspecies ofCoraSelys knowntooccurinVenezuelathelarvaofjusttwo
havebeen described,viz. C. cyaneSelys (DE MARMELS, 1982)and C. marina
Selys(NOVELO-GUTIERREZ & GONZALEZ-SORIANO, 1985).Thesetwo
are easily separated fromlarvae ofEuthoreSelys, and fromeach other, but the
hithertounknownlarvaeofC. incaSelysandofC. xanthostomaRismay resem-
blethatofCentralAmericanC. chirripaCalvertdescribedby CALVERT(1911),
whichisclosely similarinshapeofthecaudalgillstolarvaeofEuthore, notof C.
cyaneandC. marina.Thekey given heremusthencebeconsideredprovisional.
KEYTOTHEDESCRIBEDULTIMATEINSTARLARVAE OF
POLYTHORIDAEFOUNDINVENEZUELA*
1 Totallength(excl. caudal gills) lessthan 9mm: occipitallobesstronglyangledlateroposteriorly
(Figs.8-9) 2
- Totallength(excl.caudal gills)morethan 9mm;occipitallobes notobviouslyangledlateroposte-
riorly(Figs 10-11) 3
2 Foreand hindwingsheathsofapproximatelysameoutline;projectionsofcaudal gillslongand
pointed Chalcothore montgomeryi(Racenis)
—Forewingsheath narrowwithcostaland analbordersparallel;hindwingsheathbroaderwithanal
borderconvex; projectionsofcaudalgillsnotknown,butprobablyshortand blunt,asinC.ruti-
lans (Rambur)(SANTOS&COSTA, 1987) Chalcopteryxscintillans McLachlan
3 Prementumlongishand narrow(Figs 12-13);hindwingsheath slenderwith costaland anal mar-
ginsparallel(Figs 16-17) Corai 4
—Prementumappearingshorter andbroader(Figs 14-15);hindwingsheathbroader,with analbor-
derconvex(Figs 18-21) Euthore 5
4 Dorsal spines of abdomen (Fig. 22) and projections of caudal gills (Fig. 24) long and
slender Coramarina
- Dorsal spines of abdomen (Fig, 23) and projections of caudal gills (Fig. 25) short and
blunt Cora cyane
5 Total length(excl. caudal gills)less than 15mm;hind tibialessthan 4mm Euthorefasciata
—Total length(excl.caudalgills) morethan 15mm;hindtibiamorethan4mm Euthorefastigiata
*Notincluded inthekey, besides ofCoraincaand C.xanthostoma,isPolythoreterminataFraser,
asinglemaleofwhich wascollectedbyJ.W.Williamson,inTachiraState in 1920. The localitylabel
ofthis malecouldbeerroneoushowever (DEMARMELS, 1999),andthe larvaofthisspecies,and
ofthe genusPolythoreCalvertingeneral,isunknown.
EUTHOREF.FASCIATA(HAGENinSELYS, 1853)
Figures 15,18,26,28
Materi al (1 <J, 1 2,ultimateinstarlarvae;supposition:only Euthorein range). — 1 9,Ven-
ezuela,AraguaState, road Maracay-Choroni,Regresiva del Diablo (HenriPittierNational Park),
1350m, 1-VI-2000; 16,30-V-2002,bothJ.De Marmelsleg.
32 J.De Marmels
Larvabrown, verysimilarto larvaeofE.fastigiatameridanaSelysdescribedby
DE MARMELS(1995). Mandiblesas inE.fasciataplagiata(seebelow). Dorso-
medianspine ofabdominalsegment 1 minute.Ovipositorsurpassing distalbor-
derofabdominalsegment 10byadistanceequal to threequartersthelength of
thatsegment,as seenin lateralview,but thismay vary dependingon the degree
ofabdominalcontraction, whichisconsiderableinthespecimensexamined; outer
valvesofovipositor coveredwith spinules which tendto formanirregularrow
atventralborder, as wellas along dorsolateralmargin. Caudalgills(Figs 26-28)
as inE.fastigiata meridana.
Measurements (inmm). - Totallength 11-12 (noteabdominal contraction);lateralgill
3.0-3.5;headwidth 4;forewingsheath4.8-5.0;hindfemur 3;hind tibia 3.4.
REMARKS. — E. f.fasciatais commonatthe collectingspot next to a cascade
incloudforest, where itoccurs together with Coracyane and C. xanthostoma.
Figs22-30.Diagnostic larvalcharactersofVenezuelan CoraandEuthore:(22-23)skylineofabdomi-
nalsegments6-10,left lateralview,of(22)C. marina, —(23)C. cyane; - (24-27)leftlateralgill,left
lateralview,of(24) C.marina, - (25)C. cyane,— (26)E.f.fasciata, — (27)E.f.fastigiata;—(28-
29)median gill,leftlateral view,of (28)E.f.fasciata, — (29)E.f.fastigiata;— (30) abdominal seg-
ment9showingmalegonapophyses,ventralview,ofE.fasciataplagiata.
ZygopteralarvaefromVenezuela 33
Iattributethe present larvaeto Euthorefasciata, becauseof thecomparatively
broadprementumandtheroundedanalborderofthehindwing sheaths, aswell
as theirclosesimilarity withlarvaeofE.f.plagiata described herebelow.
EUTHOREFASCIATAPLAGIATA SELYS, 1873
Figures 19,30
Material (4<3,ultimateinstarlarvae;supposition:onlyEuthoreinrange). — 4<J, Venezuela,
TachiraState,Palmira,QuebradaLaFlautera, 1200 m,9-VII-2000,J.DeMarmels leg.
Larvaedarkbrownwithpaleareaarounddorsalspineonabdominalsegments
7-9,andmiddleofsegment10. Mandibleswithfourlargeteethin theouterrow,
andafifth, smallone, inthe mostmesalposition (ventral view);right mandible
additionally withsmalltoothatbaseofthefirstlargetooth(ventral view).Male
gonapophyses (Fig. 30) slightly moreprotruding distallythan in E.fastigiata.
Measurements (inmm).— Totallength12.2-13.3;lateralgill2.5-3.2;headwidth 3.9-4.0;
forewingsheath5;hind femur3.3-3.5;hindtibia 3.3-3.8.
REMARKS. - No consistentmorphological differences(besides ofsize)could
befoundbetweenlarvaeofE.f.plagiata andlarvaeofeitherE.f.fasciata orE.
fastigiata (see below). Thelarvaewere collectedinamountainstream inforest,
betweenleaflittercaughtby stonesinthefastflowingwater,andbetweenmasses
offloatingrootletsoftrees.Adultswerecommon,andafewHetaerinacruentata
(Rambur) wereobserved atthesame spot. BICK & BICK (1992) consider E.f.
fasciataandE.f.plagiataformsofonespecies basedonfemalewingcolourpat-
tern. However,femalesare polymorphic inbothsubspecies, whereasmalesshow
moreconsistentdifferences(DE MARMELS, 1988). InVenezuela, E.fplagiata
is present only around theTachira depression, while E.ffasciata hasbeenre-
cordedto thenortheast, fromBarinasStateto theCoastalCordillera.
EUTHOREF.FASTIGIATA(SELYS, 1859)
Figures 11,14,20,27,29
Material (38,19,ultimate instarlarvae;supposition:only Euthorein range).— Id,Ven-
ezuela,TachiraState,SanVicente deLaRevancha,VegaGrande, 1800m, 17-V-1999;23,1 $,8/9-
V-2002,allJ.DeMarmels leg.
Larvaedarkbrown,indistinguishable fromlarvaeofE.fastigiatameridanaSe-
lys. Mandibulardentitionisidenticalinthesetwo subspecies, i.e.fiveteethinthe
outerrow inbothmandibles, theright mandiblewitha smallaccessory toothat
thebaseofthefirstlargetooth(ventral view).Theovipositor inthefemalelarva
ofE.ffastigiata reacheswellto thedistalborderofabdominalsegment10(fe-
maleultimateinstarlarvaeofE.f.meridanahavenotbeendescribedsofar).
Measurements (inmm). —Totallength 15.3-18.0;lateralgill4.0-4.2;head width4.5-5.0;
forewingsheath6;hind femur4; hindtibia4.2-4.8,
34 J,De Marmels
REMARKS. — Thelarvaeof E.f.fastigiata were collectedin a stony stream
withina gallery forest,between masses ofrootletsoftrees intheflowing water,
andbetween leaflitterretainedby stones atspots withfastcurrent. Adults, in-
cluding tenerals, were common.NumerousHetaerinacruentata,Teinopodagrion
oscillans(Selys), afemaleCannaphila vibex(Hagen), aswellas anunknowngom-
phid, werealso recorded. BICK& BICK(1992) treatE. f.meridanaasdifferent
atthe specific levelfromE.f.fastigiata, buttheir strict allopatry, together with
theirclosesimilarity, seemto supportasubspecific status.
PSEUDOSTIGMATIDAE
MICROSTIGMA ROTUNDATUM SELYS, 1860
Figures31-39
Material (26,ultimateinstar). -Id, exuviae(reared):Venezuela,AmazonasState,km 2,
roadSan CarlosdeRioNegro-Solano,ca. 100m,4/13-1II-1984:1 S,larva(supposition)samedata,
both J.DeMarmels leg.
Larva andexuviae darkbrown, unpattemed. Headbroaderthan thorax; oc-
cipital lobesbroadly rounded, occiput concaveinmiddle(Fig. 31). Antennawith
seven segments (Fig. 32). Labium atrest reaching backwards to hindborder of
first coxae; prementum(Fig. 33) with about 20 spinules laterally in distalhalf;
medianloberounded, itsfreeborderweakly serrulate; labialpalpbearingfiveor
six (once) setae(Fig. 34); mandiblesas illustrated(Figs 35-36). Legs unpatterned,
femoraandtibiaewithunconspicuous spinules; larger spinules neartipoftibiae
andventrallyontarsalsegments.Wingsheathsreaching tomiddleofabdominal
segment 5. Spinulation ofabdominalsegment 10as illustrated(Fig. 38), its dor-
sal borderwithbroad, semicircularmedianexcision, themargin ofwhichbears
nospines; middlethirdof ventraldistalborderof samesegmentwithoutspines,
butventral surfaceofeach lateralthirdof samesegment,and ofmalegonapo-
physes withminute, tubercle-likespinules. Caudalgills ofexuviaelost, thoseof
larva damaged (Fig. 39).
Measurements (inmm). - Total length23;lateral gill(larva)4; headwidth 5;lengthof
prementum4;forewingsheath7.5-9;hind femur 6.
REMARKS. — Thelarvaewererecoveredfroma crevice inthestem ofafallen
tree inthejungle. Thiscrevicewas about70 cm longand 10cm deep; the width
ofitsopening didnot exceed 5 cm. Abundantleaflitterwas foundonthe bot-
tomofthecrevice.Fromthefivepseudostigmatid larvaeofvaryinginstarsfound
only two ultimateinstarlarvaewerecollected.Onelarvawas rearedsuccessfully,
theotherone died.Unfortunately, thealcoholinwhichtheexuviaeandthelarva
werekept laterdriedupandbothspecimens suffereddamageandpartialortotal
loss(exuviae) ofthecaudalgills.Whetheralllarvaefoundinthiscrevice, includ-
ing the onedescribed here, were Microstigma Rambur, is not known. Another
ZygopteralarvaefromVenezuela 35
pseudostigmatid species observedintheareawasMecistogasterlinearisFabricius.
ThelarvaofthelatterwasdescribedbySAHLEN& HEDSTROM(2005). Itmay
beseparated fromthatof M. rotundatumbythefewermandibularteeth,andby
thepresenceofsix palpal setae(only fiveinMicrostigma rotundatum). Nolarva
of Microstigma hasbeen formally described so far, although DE MESQUITA
Figs31-39. Microstigmarotundatum,ultimateinstar maleexuviae:(31)head and pronotum, dorsal
view; - (32)rightantenna; - (33)prementum,ventralview; - (34)rightlabialpalp,dorsalview; -
(35)rightmandible,ventral view; - (36)leftmandible,ventralview; - (37)apicalportionofabdo-
men,leftlateralview;- (38) abdominalsegment10,leftlateralview;- (39)tipofabdomenshowing
rightlateralandmedian gills,rightlateral view - (Note:Fig. 39isofsupposedlarva).
36 J.De Marmels
(1992)presented apaperwitha description ofthelarvaofM. maculatumSelys,
during the4thBrazilianLimnological Congress.
PLATYSTICTIDAE
PALAEMNEMA CLEMENTIA SELYS, 1886
Figures40-44
Material (3 d, 12,ultimateinstar exuviae: males takentogetherwithemergingadults). — I
3,Venezuela,TachiraState,San Felix,QuebradaLaResbalosa,350m, 16/23-VI-1998; 1 d, 19-V-
1999;12,1l-VII-2000;1 3, 12-V-2002,allJ.De Marmels leg.
Exuviaepaleyellowish brown, unpatterned; frons, clypeus, labrumandlabial
palps ferruginous; freeborder oflabrumfringed with long, hair-likesetae; ba-
sal socket of antenna bearing a groupof five or six such setae; afewsetae also
along central portion of concave occipital border and along ecdysial line, on
vertexes well as on postocular lobesnear lateralangle; a row of shortersetae
also laterally andventrally along hindborder ofcompound eye. Antennawith
Figs40-44.Palaemnema clementia,ultimateinstarexuviae: (40)left antenna, male; — (41)anterior
portionoflabium,male,dorsalview; —(42)tipofabdomenwithovipositor,leftlateralview; —(43)
rightlateral gill,male,leftlateral (internal)view;— (44)median gill,male,leftlateral view.