A month ago in Yen Bai I caught a male Periaeschna sp. that at the time I thought solved a problem I ran into a week earlier. At that time I had seen a male Periaeschna hanging in a bush, but failed to catch it. The weekend after I caught a Periaeschna in the same general area and sort of wanted to associate it with the earlier male. Nevertheless the color of the eyes seemed different, the leg color was not blackish and the color of thorax and stripes seemed brown and yellow-green, not blackish brown and green. Recently I bumped into other Periaeschnids, in Ba Vi and in Xuan Son, both a female and several males. These convinced me that the Yen Bai Periaeschnids, apart from the one hanging in the bush, were something else. I have adjusted that entry into Periaeschna sp. But what is then Periaeschna magdalena? Taiwanese P. magdalena seem not as green, more yellow, as their thoracic stripes are concerned, and their eyes are not blueish, but yellow-green. Now, this may be geographic differences, and for the moment I will consider them as such, but I have a gnawing suspicion that there is more even than meets the eye and that these may be separate species. Maybe the answer lies in P. nocturnalis. This species could well be it, but the color of the eyes is not mentioned in Asahina (1986). There is unclarity relating to the occurrence of nocturnalis/magdalena in Vietnam. Karube (2004) regards the Vietnamese material as P. magdalena.
I have not been able to find a drawing of the penis, but I did take a picture. Maybe someone has material to compare it with?
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Periaeschna magdalena, female, Ba Vi, May 25 |
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Close-up of wing-base |
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Male Periaeschna magdalena, Xuan Son, June 8 |
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Another male from Xuan Son, June 1 |
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Appendages in ventral view of June 8 male |
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Apical segment of penis |
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Lateral view of same individual |
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The appendages in dorsal view of the June 1 male, distorted on one side |
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Scan of female from Ba Vi |
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Scan of Xuan Son male of June 1 |
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Xuan Son male of June 8 |
Karube have told me already that the Taiwanese Periaeschna probably represnets a new and distinct species from true P. magdalena. The differences between them are quite evident when comparing your photos with mine of Taiwanese Periaeschna.
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