장음표시 사용
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BIOGEOGRAPHY AND EVOLUTION OF OREAL LEPIDOPTERA
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OBSERVATIONS ON THE MATER COGNITION AND COPULATORYREHAVIOUR OF AESHNA CYANEA MULLER) ANIS OPTER A AESHNIDAE)A. AMBRUS
Iurisich u. I6. H-949I GPhiaria, HungaryTwo different night patierias of Aestina cyanea MULLER) were studied at the maling placewith the application Of capture-mark-retense techniqueS. The mate recognition abili ty of the males was investigated experimental ly with the fishing-line technique and lamates in hando the male turned out to recogniZe the sitiing segglaying)semale with a special female-searching 1 ight. The males tried to copulate with a tethered female, a se male held in hand and even a male held in hand. Super 8 nam movi e film was taken on certain acts of the lila cycle of A. cyanea, including the recognition os sitiing semales and other acts of the maling. The hypothesis of the dualfunction of the precopulatory sperm translocation - as a tool of male recognition - is delat-led here. Steps of the hypothetical male recognition system are drasted for closely related aestini d. gomphid. corduli id and cordulegasterid species based On preserved infecis. Key wOrds AeShria Cyanea, Odonata, male recognition, copulatory bellaviOur
A estina cyanea MULLER) is one of the most rapid vigorous ly nying large dragoni lies in Central Europe. It is no wonder that there are many papers de alii gwith this species, e specialty the territoriali ty of the males. Studies have been made on the time-sharing system of patrolling males at the maling place POETH KE 9 KAISER l98β); the density-dependent bellavi our os males POETHKE l 988) the bellavi our of females at the maling place AISER l 98 ) and so on. The well-de vel oped density-dependent territoriali ty of the males and therecognition abi lily of siti ing females makes this species useful for investigat ingilie male recognition and copulatory bellavi our os a large dragoni ly. This paper pre Sent S the non-quantitati Ve records of capture-mark-re lease CM R) studies combined with experimental studies on the reproductive bellavi our of the adulis. The working hypothesis was that the precopulatory movemenis includ ingintra- male sperna trans location) are the most important factors in the mate recognition proces s when the male gets close to the fe male. The refore experiments were designed to imitate the natural male-la male encounters to achie Ve copulations with in reach. They were documented on Super 8 iram movie film. The low
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speed replays made it possibie to stud y the move ments of copulation in delatis which have led to a new interpretation of the precopulatory Sperna tranS location.
Two typical habitats of A. cytinea were studied in Hungary. One at Tatabanya described in AMBRUS l 992)J. another on Sopron. at the Nw horder of Hungary. The lalter consists of twoponds of nearly 0.l and 0. 3 hectares of Open water, severat hundred meters away Dona euch ollier. The legit, of the shoretine of the two ponds could allow approximately 9 and id males smaximum)to patrol at the Same time. Multiple CVR studies were carried Out in Tatabanya in l986. and in Sopron in l98J. l 989 and l990. Experimental studies with semales and movi e film were carried Out in the last two occasions. The most extensive study was made belween d August and 26 october, l989. with 4J sam-ples concerning more thaia 500 captures, and recaptures or registrations without capture os 204 individuat s. including 28 captures Or registrations of 24 semales. As many as 50 semales were observed when persorining Such activities aS egglaying, sine lingor mating. Eight specimens of the captured semales were used as attractant sor males nying on sishing-line, fastened to the trian k on the ground or heid in hancl. to attraci males. Other semales were simply released frona hand when males came close to them or just when grasped them. Some moments were sit med with a Sankyo ES 4 XL camera with a silmspeed os l8 Danaestsec. The study was repeated in l990 with sonae extensions and res inemenis to the methods. Males in hand were used also to attraci patrollisag males. Females were fastened to a telescope stichinstat ted on the camera fixed sociis). Frames of the movi e silm were stud ted and counted to estimate the tength of certain acis.
OBSERVATIONS ON PATROLLING MALES
when there are no conspecific males.
they usual ly try to come close to them. The nexi Steps are any of the agressi Ve
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MATE RECOGNITION AND COPULATORY BEHAVIOUR OF A. CYANEA
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hut accurate tim ing was made Only in one case. A fe male was released hom handjust when a male approached her and the movements were fit med. It lasted for 2 seconds 36 frames) Dona the grasping and landing on the thorax of the female tothe completed wheel. MDVemeritS Ofta ing the semale Based on fit med evenis with fastened females the motions os a male thathas recogniZed a female are l. landing on the thorax of the se male 2. selecting the right direction sis necessary), 3. grasping the head of the female with final appendages lower on the occi-put Upper bellind the compotand eyes), 4. taking on frona the thorax and moving forward with a very shori stop x 0.lf sec, n l0, sd α 0.0β sec), after whichola. the sperna translocation may be performed. In the fame moment thehead of the female can touch the ventral si de of the metathorax and l-2 abdominat segments of the male. In the case of tethered females, the males returned to the thorax of the fe- males and tried to bring them to copulation by stimulating the head with openedmandi bies inconsiderately. In the case of Deely moving females, the last step, the irrigation of the head is absent hecati se the se male heiads her abdomen just when the male moves for-ward. and the wheel is completed without clear tandem sso me doZen cases without accurate tim ing).COPulatiori The duration os copulation is known to be long KAISER l9 4). Here are two incomplete timing accurate stat ting time of the copulations unknown) whichshow that the patring must last for at least one hour. The durations os copulations with females on fishing-line were not timed. but the movements of the 2 3 abdominat segments of males were detected. The process of sperna trans location is
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MATE RECOGNITION AND COPULATORY BEHAVIOUR OF A. CYANEA
Sperna trans location ST) performed by PnA males alone at the shoretine ornear the shore was observed in two occasions in both l 986 and l 989. and on oneoccasion in l990. The sperna content of the copulatory organ of the males was not isvestigated.
One male was observed three times whicli has a native fauit on his abdomen pre- venting him to perform ST. This specimen was always extremely agressi Ve. Sometimes; at the early stage of the nying season the females can show
males can obvio us ly recogniZe the sultable places as they lay eggs alone and frequently use the Same substrate in a gi ven biotope. The WAY males usualty visit just the fame, sheltered places looking for se males. The abi lily of males to recogniZe the siti ing 1 emales can give evidence for this hypothesis in the case of A. Cyanea. But we haVe no information abolit the causes of individual differences
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between the mate recognition abili ty of A. cyanea males mentioned before. In case of the A. cyanea, the inductive effect of previolis maling success quasi learning process), andior the amount of producedistored sperna fas stimulant: see the case of the male with abdominat mal formation) could be possibi e causal factor of individual differe iaces. The generat recognition abili ty of A. cyanea males of the sitiing females and the clear WAY display is not a common attribute of anisopieran males. UT-
interest in the landed females and ny away, as demonstrated by fishing-line experiments AMBRUS, uia published). Simple observations of Ormetrum ciancellatum stlowed that the males were not interested in the sitiing se male while restingas close to her as 30 O cm. but immediate ly stat ted to chase her and grasped herwhen sile took off AMBRUS unpubiis hed). The mate recognition abili ty of A. cytinea males offered good opportuni tyfor investigat ing the maling procedure in-depth, and to analyse it Step-hy-steps rona the view-point of reproductive i solation barrier in the sense of TENNESSEN
Visual stimuli must he essentiat factors of male recognition. The remote visual stimulus may be first os ali the flight manner of the se male. as the male tends to lose interest in the exhausted, unusual ly slowly flying female on a fishing-line, despite of her correct colouration hut is interested sexualty in the males lying in se male-manner sescaping frona the water) despite of his male colour
This study cannot give evidence for the recognition os conspecific night patiern andior colouration as remote visual stimuli. as it should he stud ted in amixed population with such similar Species as AeShnia junceia, A. SuharCticia Or A. viridis. In this case AeShnia muta was the single aestin id species present at thepond which was never attacked sexu atly by A. CFGHeia maleS. While only the existence of the remote visual stimuli is certain, the close visual stimuli are known beller as regariis their functioning. The males recogniZing the conspecific individual in hand with abdomen covered by fingers) comecloser, land on the thorax and try to copulate should the ''mateV he a se male or a male. As the abdomen was invisibie, covered by fingers except for the very basalarea, the thorax must holit the specific uni sexual) visual stimuli on the dorsalside: the complex patieria of wingbase and the mesepisternat stri pes. Furthei more the colour patieria of the head and the abdomen base may offer additional specificin formation. but the significant difference belween the colouration of the sexes Seems not to affect the interest of the approaching male in the individual held in hancl. It was also found in the case of the male in hand with the abdomen tess
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MATE RECOGNITION AND COPULATORY BEHAVIOUR OF A. CYANEA
covered. so the distinctive colouration of the male acting as close visual stimuliwithout agressive bellavi oui . does not provoke the attack of the approachingmate. But the colour patieria of the dorsal vlew of the thorax may give clue abo ut
the right direction of landing and placing the final appendages. The nexi steps in male recognition are clasping the head of the se male hythe final appendages and the precopulatory ST whicli is usualty combined withthe movement of the lamale's abdomen cui ving forward to the wheel position. As this is one of the most important phases of patring when the pre-copula turn SOut to hecome copula or not depending on the readyness of the female throughreflex- like actions, we Should pay more attention to thi S Stage.
There is the exact print of upper appendages of male on the back side of the head of both sexes). including the final curved spine. The lower appendage sits to the occipiat as well. Presumably there are receptors whicli can be stimulatedon ly with the specific appendages fas correct keys). As the final appendages of males are Species-specific, the tactile stimuli may work with the lock-and-keymechanism. It is not easy to test this supposition, but the proces s may be lookedat in directly the incompatibili ty of the final appendages to the head of the se maleatone cloes not prevent the tandem linkage. But the heterospecific tandem does not make copula too frequently as it is mentioned by BICK Ω BICK sl 98 l). I
os maling. UTZERI sl 98β) has reported ii observations by different authors onST performed by a male dragonny alone. AMBRUS l 990) considered the ST tobe common at the end of the pre-reproductive period of Cordulia aenea awayfrona the water. MILLER l 984) found sperna in the secondary genitalia os sonae males of libellulid dragonfli es and supposed that they could controi the amount of sperna released. The sperna amount stored in the secondary genitalia of A. Cyanea was not in Vestigated here, but obvious ly A. cyanea males can hold it asthe pre-copulatory ST may be performed alone. Neveriheless the males do ST he- fore copulation: but why. does it have another function During pre-copulatory ST the head of the se male come close to the venti alside of the l-2 abdominat segments and metathorax of the male or reatly the ver-