The larvae of Teinopodagrion caquetanum De Marmels and T. vallenatum De Marmels (Zygoptera: Megapodagrionidae)

2007·2.1 MB·English

by  Pérez-Gutiérrez, L A

Odonatologica36(3):307-313 SeptemberI,2007
Thelarvaeof
Teinopodagrioncaquetanum De Marmels
and T. vallenatum DeMarmels
(Zygoptera: Megapodagrionidae)
L.A.Pérez-Gutiérrez
Laboratorio deZoologíayEcologíaAcuática,DepartamentodeCiencias Biológicas,
Universidad deLosAndes,Carrera 1N° 18A 10,Bogotá,Colombia
[email protected]
ReceivedFebruary23,2007/ RevisedandAcceptedApril3,2007
Thelastinstarlarvaearedescribed andillustrated.Theyarediagnosedagainstthe
congeners onthebasis ofpublisheddescriptions.Theprincipal diagnosticfeatures
arefound in caudal gills, cerci and protuberancesof occipitallobes. Akeytothe
known Teinopodagrionlarvaeisprovided.
INTRODUCTION
Megapodagrionidae is apantropically distributedfamily. Thelarvalstagesof
mostspecies are unknown, especially thoseoftheneotropical taxa. Teinopoda-
grioniswelldistributedalongtheAndesmountainrange.DEMARMELS(2001)
reportsforColombiaT. caquetanum, T.macropus,T. mercenarium,T. muzanum,
T. oscillans, T. temporale. T.vallenatum, andas possible residents.T. curtum, T.
turikum, T. venaleand T. vilorianum.Sofar25species areknown, andthe larval
stagesofonlyfouroftheseweredescribed(DEMARMELS, 1982, 2001; VON
ELLENRIEDER, 2006). The following descriptions of 77 caquetanumand 77
vallenatumlarvaewill bringthetotalnumberto six.
MATERIALANDMETHODS
Larvae werepreservedin 75%ethyl alcohol and depositedintheentomologicalcollection ofthe
NaturalHistoryMuseumoftheUniversidad delos Andes(UNIANDES), Bogota.Drawingswere
made usingastereoscopeZeiss Stemi SV6coupledtoacameralucida. Measurements aregivenin
millimeters,total lengthincludes gills.
308 L.A. Perez-Gutierrez
TEINOPODAGRION CAQUETANUM DE MARMELS,2001
Figures2,4,7,9,11,13,16,18,19
Material. — 26 last instarlarvae. Colombia: Meta,Villavicencio,vereda La Argentina,594
m a.s.1, 10-XII-2004,L. Perez leg.
Generalcolourof larvaeterra cotta, presumably due to some ferrouscom-
pound covering body. Legs long, gillsshortandslender.
Head. — 1.6timesas wideas long, occiputconcave, occipital lobeswithslen-
der, conicalprotuberances (Fig. 2).Antenna6-segmented; firstandsecondseg-
mentsofaproximately samesize;withoutanydiscerniblecolourpattern, butwith
somemediansizedhairs(Fig.4). Articulationofpre-andpostmentumbetween
first pairoflegs, maximumwidthofprementumat 67, 56%itslength. External
margin devoidof spines, ligula moderately convex, finely serrate, mediancleft
shallow, prementumandpalpdevoidofsetaeandspines(Fig. 7). Movablehook
longer thanexternaledge of palp. Palp withthree teeth, ofwhich internaland
externalones are approximately the samesize; mediantoothtwicetheirlength.
Mandibularformula(sensu WATSON. 1956) L T12340a(m1234)b; R T 1234y
a(m°)b(Fig. 9).
Thorax. — Prothoraxnarrower than head, withdorsolateralconicalpro-
jections of same size as thoseon occipital lobes (Fig. 2). Legs withoutany dis-
Figs 1-7.Last larval instarofT.vallenatum (Figs 1, 3,5,6) and T.caquetanum (Figs2,4,7): (1-2)
head,dorsalview; - (3-4)rightantenna, dorsal view; - (5)prementum;- (6-7)prementum,dor-
sal view.
Larvae ofTeinopodagrioncaquetanum and T.vallenatum 309
cemiblecolourpattern (Fig. 11). Flat meso- and metathoraxirregularly black
patterned. Posteriorwingpads surpassing proximal borderofS5.
Abdomen. — Without any discerniblecolourpattern, but with a small
bluntprotuberance onS6andslenderdorsalhooksonS7, 8,and9.HookonS9
surpassing length ofsegmentposteriorly (Fig. 13),distalborderofS10without
triangular incision. Abdomen/lateralgill length proportion is 66, 15% (Tab. I).
Lateralgillstriquetral,mediangillfoliaceous; pointed andprolongued, without
any discerniblecolourpattern. (Fig 16).Cerci elongate withcurved dorsaland
ventraledges, andwithblunttip directeddownwards(Fig. 18).Gonaphophyses
small, unpatterned andwithoutspines (Fig. 19).
Measurements (inmm). - Total length:17.8(including gills),median gill4.5,lateral gill
5.3.
HABITAT. — Larvaewere collectedfroma smallstream in thefoothillsofthe
ColombianEasternCordillera, whichdrainsto theOrinoco. Ithasasandy bed,
presenting a ferrouscompound which tinged the larvaewith aterracotta col-
ouration.Theassociated riparian forestis heavily fragmented andcomposed of
endemicshrubsandtrees fromthetropical lowlandrainforest.
TEINOPODAGRION VALLENATUM DE MARMELS,2001
Figures 1,3,5,6,8, 10,12, 14,15,17,20
Material. - 3d last instar larvae. Colombia: Magdalena,Santa Marta, SierraNevada de
Santa Marta, QuebradaMalabrigo,ViaCerro Kennedy, 1600m a.s.1, 1 d,20-X-200I. Colombia:
Magdalena,Santa Marta, Sierra Nevada deSanta Marta,QuebradaHarimaca, 800m a.s.l., 1 <J,
13-IV-2005. Colombia: Magdalena,Santa Marta,Sierra Nevada deSanta Marta,Rio Gaira,Pozo
Azul, 1100ma.s.l.,1 S, 11-11-2006.
Larvapalewithconspicuous darkstripes on caudalgillsandlegs (Fig. 14).
Head. — Triangular, occiput concave (Fig. 3); conicalprotuberances ofoc-
cipital lobesnotstrongly protruding. Antenna6-segmented, being the firstseg-
mentthelargest,secondandthirdseg- Table I
ments withdark stripe, stripe on sec- Dimension proportion ofsome body parts of
ond segment located at middle and T.caquetanum and T. vallenatum
presentssomefine hairs,onthird seg- PPrrooppoorrttiioonn ccaaqquueettaannuumm vvaalllleennaattuumm
ment thedark stripe morebasally lo-
cated(Fig. 5).Articulationofpre-and LLoonnggiittuuddee 8844%% 8800%%
postmentumlocatedbetweenfirstpair cceennttrraall//llaatteerraall ggiillll
of legs, maximum width of premen- WWiiddtthh//lloonnggiittuuddee 1133..77%% 1177..55%%
WWiiddtthh//lloonnggiittuuddee 88..44%% 1111..2266%%
tum at72%itslength. Palpal andpre- llaatteerraallggiillll
mental setaeabsent(sensu CORBET, WWiiddtthh//lloonnggiittuuddee 6677..5566%% 7722%%
1953),lateraledgeofprementurnbeset pprreemmeennttuumm
withshortspinesalongitsentirelength LLoonnggiittuuddee 6666..1155%% 8833%%
(Figs5,6). Mandibularformula(sensu llaatteerraall ggiillll//aabbddoommeenn
310 L.A.Perez-Gutierrez
WATSON, 1956)L IT234
0a(m12'4)b;R T 1234ya
(m°)b(Fig. 8).
Thorax. — Pro- and
mesothorax dorsally
presents acordiformblack
spot, itsbluntendbecomes
visibleand extends up to
the wing pads insertion
point (Fig. 14). Wing pads
extending to base of S8.
Femora with three black
stripes, of whichthe most
basal one being narrower
andleastconspicuous. Tib-
iae and tarsi pale, unpat-
terned (Fig. 10), covered
with short spines, the first
spine is longer, claws sim-
ple.
Abdomen. — With
protruding lateralkeels on
S1-S8. Abdomen/lateral
gill length proportion is
83% (Tab. I). Blunt dorsal
hookspresentonS6-S9be-
ing theoneonS6thesmall-
Figs 8-13. Last larval instar of T. vallenatum (Figs8, 10, 12)
and T.caquetanum (Figs9, 11,13):(8-9)mandibles,inner view; est(Fig. 12). Distalborder
— (10-11)anteriorlegs, dorsal view; — (12-13)abdomen,lat- of S10 with asmallweak-
eralview. ly marked triangular inci-
sion; maximumwidth ofabdomenat S5 and S6, S9 is the narrowest. Caudal
gillslong, lateralgillstriquetral,mediangillfoliaceous, thelattervisibly shorter,
widerand withblunt tip (Fig. 15).All threegills besetwith spines along entire
borders, thesespines being largeranddenser towardstips. Twowidetransverse
darkbandsonall three gills,besidesof irregularly dispersed spots. Malegona-
pophyses smallandtriangular, finely spinous ventrally (Fig. 20). Cerci shortand
blunt, dorsaledge in basalhalfarched downwards, ventraledge arched upwards
in distalhalf (Fig. 17).
Measurements (inmm). - Totallength:20.7(including gills),median gill:6.7,lateralgill:
8.7.
habitat. — Thelarvaewerecollectedinamountainstream withheavy sand
bottomand slowcurrent inwell-preserved riparian forestin drytropical forest.
Larvae ofTeinopodagrioncaquetanum and T vallenalum 311
KEY TOTHE LAST LARVALINSTAROF TEINOPODAGRION
(MODIFIED FROM VON ELLENRIEDER, 2006)
1 Malecercuscylindrical 2
— Malecercustaperingtoend 3
2 (1)LabiumextendingbeyondcoxaeII;caudallamellae shorterthanabdomen;wingcasesextend-
ingtoendofS6;tibiaeunpattemed;abdomenwithdarklongitudinalmarksanddorsal hookson
S5-9;Venezuela andColombia oscillans
— LabiumextendingtobetweencoxaeIand II;caudallamellae shorter than abdomen;wingcases
extendingtoendofS5;tibiaewithonebasal darkband;abdomen paleandwithdorsalhookson
SI- 9,thoseon2-5minute;PeruandBolivia decipiens
3 Tibiaeunpattemed;wingcasesextendingtobeginningorslightlydistaltobeginning,ofS5;dor-
salhooksonS5-9;Venezuela andColombia venale
— Tibiaewithorwithoutbasalspots;caudallamellae longerorshorterthan abdomen 4
4 Tibiaewiththreebasalspots;caudallamellae longerthan abdomen;wingcasesextendingtoend
ofS5;dorsalhooksonSI-9Bolivia and Argentina meridionale
— Tibiaewithout basal spots;caudallamellae shorterthan abdomen;dorsal hooksonS6-9 5
5 WingcasesextendingtobeginningofS5; antennalsegmentsunpatterned;blunt protuberanceon
S6andslender dorsalhooksand increasinginsizefrom7,8, and9 caquetanum
— WingcasesextendingtobeginningS8;secondandthirdantennal segmentswithdarkstripes;dor-
salhooksofS7,S8andS9areverysimilar insize,onS6issmall.(EndemictoSierraNevada de
Santa Marta,Colombia) vallenatum
DISCUSSION
T. vallenatum is an endemic species of the Sierra
NevadaofSantaMarta(DE MARMELS, 2001). Its
knownaltitudinaldistributionvariesfrom800ma.s.l.
inMinca, PozoAzulsiteto 1600ma.s.l inQuebrada
Malabrigo. T. caquetanumisfoundinthefoothillsof
theColombianEasternCordillerawhichdrainstothe
Orinocobasin.
T. caquetanumand T. vallenatumlarvae are quite
similarin general appearance.Diagnostic characters
of T vallenatumare:
DorsalhooksarepresentonS6-S9, thatonS6isvery
small, hooksofS7, S8andS9 are very similarin size
and thickness; abdomenhas lateralkeels similar to
those foundin larvaeofHetaerina(Calopterygidae).
In T caquetanumthe dorsalhooks are moreslender
thanin T. vallenatum, and only thoseon S8 and S9
are similar insize.
Fig. 14.Teinopodagrionvallenatum: last larval instar,generalas-
pect.
312 L.A.Perez-Gutierrez
Median gill in T. vallena-
tum presents an intermedi-
ate widthbetween those of
T. venaleandT. oscillans, be-
sidesofhavingablunttip.In
T. caquetanumthemediangill
isvery small.
Cercus of T. vallenatum
male is evidently different
fromthatof T. venaleand T.
oscillans. Inthesetwospecies
thecercusisdirectedupwards
andhas smoothedges, while
in T. vallenatumthe edges of
cercus show sudden change
intheirdirectiontowardstip,
e. g., with dorsalmargin di-
rected downwards in basal
half,andwithventralmargin
arched upwards indistalhalf
ofcercus(Fig. 17).Segments
2and 3ofthe antenna ofT.
Figs15-20,LastlarvalinstarofT.vallenatum (Figs15,17,20) vallenatumhavedarkstripes;
and T.caquetanum (Figs 16,18, 19):(15-16)caudallamellae, segment 2 presents few and
lateralview;—(17-18)cercus,dorsalandlateralviews;—(19-
20)gonapophyses, - [Figs 17-20 nottoscale] relativelyshorthairs,segment
3hasnohairs. Neither T. ve-
nalenor T. oscillansshowsdarkstripes or hairson antennae. Wing padsextend
toanteriormarginofS8in T.oscillans, whileinT. venaletheyjust reachto S5.
ThemaindifferencesbetweenT. vallenatumand T.caquetanumlay intheshape
ofcerci, projections ofoccipital lobesand pronotum. (Figs 2, 3).Thelatter in
T. vallenatumis devoidoflateralprojections andalmost rounded;the occipital
lobesshow small, scale-likeprojections andwiderthanin T. caquetanum.
ACKNOWLEDGEMENTS
ThanksareduetoDrJURGDEMARMELSforhiscommentsonthemanuscript,andtotheRe-
search CommitteeoftheFacultyofSciencesoftheUniversidad deLosAndes,Bogota,forthefund-
ingpart ofthisproject,aswellastothe Laboratorio deZoologiayEcologiaAcuatica (LAZOEA)
ofthesameuniversityforallowinguseoftheequipmentandtheirinstallations forthedevelopment
oftheproject.
Larvae ofTeinopodagrioncaquetanum and T.vallenatum 313
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