Description of the larva of Coenagrion intermedium Lohman, 1990 from Crete, Greece (Zygoptera: Coenagrionidae)

4 Pages·1991·0.58 MB·English

by  Battin, T

Odonatologica20(3):333-336 SeptemberI, 1991
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Descriptionofthelarva ofCoenagrionintermedium
Lohman, 1990from Crete, Greece
(Zygoptera: Coenagrionidae)
T. Battin
InstitutfurZoologie,Universitat Wien,Althanstrasse 14,A-1090 Wien, Austria
ReceivedFebruary 22, 1991 /AcceptedMay 24, 1991
The ultimateinstar isdescribed and figured,based onexuviae and larvae from
Crete, Greece.Itisthefirst larvadescribed ofasp. oftheeasternmediterranean C.
puc/Za-complex.Briefnotesonthehabitat areprovided.
INTRODUCTION
Coenagrion intermediumwasfirstdescribedasasubspecies ofC.ponticumby
LOHMANN (1990a). However, most recent studies show that species rank
wouldbetterfit theCretanpopulation (Battin, inpreparation). C. intermedium
maybeexpected tobeendemic to theislandofCrete.
Atpresent,informationonlarvaltaxonomyoftherepresentativesofthegenus
Coenagrion in theeastern Mediterraneanis practically non-existent.
UltimateinstarlarvaeofC. intermediumwerecollectedfromastreamletnear
Fodhele, Crete and successfully rearedto theadult stage. The description and
figuresarebasedonlarvaeandexuviae, bothmaleandfemale.Terminologyused
forthelabiumis adopted fromCORBET (1953).
DESCRIPTION
Material. —5$and 2$iarvae,3S and 2$exuviae(preservedin70%ethanol),Fodhele, W.
Iraklion,Crete,Greece (35°22'N,24°57'E), I8-V-1988.C. Woreadou(Univ.Crete)leg,;the adults
emergedinVienna,29-V/4-VI-I988.
Thelarvaisofthetypical Coenagrionhabitus.Theground colourisbrownish,
withoutsignificant patterns.
334 T.Battin
Measurements (inmm).— Bodylength(excludingantennaeand caudal lamellae): 12.5;—
antennae:2.6;—caudal appendages5.5;—praementum,length:2.7;width 1.9;—prothoracalleg
(femur-tibia-tarsi):2.0-2.5-1.4; —metathoracal leg: 2.6-3.0-1.2;— metathoracal leg: 2.9-3.4-1.2.
Antennae 7-segmented, pedicellus about twice as long as scapus (Fig. 1).
Postocularregionwithsmall-spotcolouringandrudimentary spine shaped setae.
Ventralmarginofeye witha row ofspiniform setae.
Prementum(Fig. 2)with5 equallysized premental setae. Thedistalmarginof
the medianlobe presents very small, blunt spines (Fig. 3). Each labialpalp
provided with7palpalsetae,aboutaslongasthemovablehook.Distalmarginof
labialpalps(Fig. 4)with5to7bluntteethandastrong,inwardcurvedendhook.
Mandibles(Fig.5)armedwith4-5unequallysizedouterteeth,connectedoneach
sideto apointed lateraltooth.Innermarginwith astout,solitary tooth.Maxilla
(Fig. 6)withgaleasimple andprovided with diminutive,slightly featheredsetae,
thelaciniawith5unequally sized,largecurvedandstrongteethaswellaswith5-6
smaller ones.
Wing sheaths reaching about the posterior third of abdominalsegment 4.
Proximalpart offemoraincompletely and distalparts distinctlybanded with
dark brown. Theinsideofthe apical tibiaeis densely provided with tridentate
setae,whileunidentate,featheredsetae arepredominant ontheinnersideoftarsi.
Femalegonapophysis (Fig. 7)extending totheposteriorborderofsegment10.
The apexofthe valvulapresents 2 sharp spiniform setae. Male genitalia as in
Figure 8. Caudal lamellaewithout distinct pigmentation (Fig. 9). Nodal line
undulated, apices slightly pointed. Median caudal lamella: dorsal margin of
antenodalpart with strong spiniform setae, postnodal part densely set with
piliformsetae.Ventrally, spiniformandpiliformsetaeshorterandless denselyset
than dorsally. Inlateral caudallamellaedorsoventralposition and shaping of
setae reversed with respect to themedianone.
NOTES ON HABITAT
The larvae of C. intermedium were collected in the permanent part of a
streamlet, mainly surroundedby cultivatedareas. In Augustthewater tempera-
turevariesbetween19.5and20°Cwithanoxygen concentrationofabout78mg/1
and a pH ofabout 7.6. In riffle areas the substrate predominantly consists of
stones andgravel. Important amounts ofdetritus deposits are accumulated in
pools. The anisopteran faunaofthestreamletis rathervaried,otherassociated
Zygoptera were Calopteryxsplendens and Ischnuraelegans ebneri.
Figs I-9,Coenagrionintermedium (Lohmann):(I)antenna;— (2)labium,innerviewofprementum;
—(3)distal marginofprementum; —(4)rightlabialpalpofprementum;— (5)leftmandible,inner
side;— (6)rightmaxilla,inner side; —(7)end offemale abdomen,left lateralview; —(8)male
gonapophysis,ventralview;—(9)median(a), andlateral(b)caudallamella. —[ScalebarforFigsI,
2,4,7,8, 9: Imm;—forFigs 3,5,6:0,5mm].
LarvaofCoenagrionintermedium 335
336 T. Battin
DISCUSSION
This is thefirst larva described fromthe eastern MediterraneanCoenagrion
puella-complex sensuLOHMAN(1990b),originallyincludingC.syriacum, C.p.
ponticum, C.p. intermediumand C. puella. Striking affinities can benoticed
betweenthelarvaofC. intermediumandthe descriptionbyCARCHINI (1983)
ofC.puellafromItaly,which, bytheway,cannot beclearly differentiatedfrom
Italian C.pulchellum. However, becauseof the rather high intraspecific varia-
bilityofsomediagnosticfeaturesincoenagrionid larvae(e.g. GARDNER, 1977),
itwouldbeprematureto draw anyconclusionsfromthesescantydataasto the
taxonomicaffinitieswithinthespecies complex atthis stage.
ACKNOWLEDGEMENTS
1would liketothank CATHERINA WOREADOU(University ofCrete)forcollectingthelarval
material and JOHANN WAR1NGER (University ofVienna)forreading anearlier draft ofthis
paper.
REFERENCES
CARCH1N1,G.,1983.AkeytotheItalianodonatelarvae. Soc.int.odonatol.rapidComm.(Suppl.)
I: 1-101.
CORBET,P.S., 1953.Aterminologyforthelabium oflarval Odonata, Entomologist86: 191-196.
GARDNER, A.E., 1985. A key tolarvae. — ln: P.S. Corbet, C. Longfield& N.W. Moore,
Dragonflies,pp. 191-223,Collins, London.
LOHMANN, H., 1990a. Coenagrionponticum intermedium subspec. nov. vonder Insel Kreta,
Griechenland (Odonata:Coenagrionidae).Opusc.zool.ßumin.54: 1-7.
LOHMANN, H., 1990b. Revision der Coenagrion puella-Artengruppe (Zygoptera: Coena-
grionidae).Unpublishedmanuscript.