Thread subject: Diptera.info :: big dragonfly

Posted by Matteo86photonature on 28-07-2008 19:19
#1

HI,
I don't know if is possible know the ID from this pic,
but I try to show:
I found this big Odonata (size 8/9 centimeters) in mountain (near a little alpine pond) at about 1900 meters altitude on Italian Alps, this month.
Someone knows the id?



img516.imageshack.us/img516/8568/810368ai7.jpg

Posted by Susan R Walter on 28-07-2008 20:08
#2

I would say Aeschna juncea.

Posted by cosmln on 28-07-2008 20:48
#3

IMO this is a female of Aeshna subarctica.

very brown, including the leading edge of the wing. on A.juncea this is yellow. the thorax is more or less uniform bluish (i refer at the markings from there). on the A.juncea this will be a gradient from yellow to blue.
will be nice if you have some other angles shots? a lateral one in which you can see the back of the eye? if he is a yellow point this is A.juncea, no yellow point will go to A.subarctica.

hope this helps you,
cosmln

Posted by Susan R Walter on 28-07-2008 22:52
#4

Cosmin - it seems juncea and subarctica are very similar species and I am not familiar in the field with subarctica, so you could be right. I noted the browness of the body, and it does seem rather pale overall for juncea, but the true colour of the wing leading edge may be difficult to judge from this photo. The impression of large size may be a point in favour of juncea.

I too would like to see more photos.

Posted by cosmln on 28-07-2008 22:59
#5

Susan R Walter wrote:
Cosmin - it seems juncea and subarctica are very similar species and I am not familiar in the field with subarctica, so you could be right. I noted the browness of the body, and it does seem rather pale overall for juncea, but the true colour of the wing leading edge may be difficult to judge from this photo. The impression of large size may be a point in favour of juncea.

I too would like to see more photos.


Yes i know, that this two are very alike.
I have never seen A.subarctica, but this is not like A.juncea I see here. Several exemplary seen couple of days back. And i have seen a lot of specimens (+40 in hand), all ages. But this looks different.

Maybe will see some more photos.

Also i will continue to search for A.subarctica in Romania, still have not been found.

cosmln

p.s.
completing [EDIT]
- also the anal appendage looks like from A.subarctica (at A.juncea are more slim, just checked also in exemplary i have in collection)
- Italian Alps is a known areal for A.subarctica (so will not be something new)

cosmln

Edited by cosmln on 28-07-2008 23:02

Posted by Matteo86photonature on 29-07-2008 07:00
#6

Thank you very much Cosmin and Susan

Unfortunatly this is the only shot I did because "she" went away quickly.

I know that for expert this could be ugly but as we have just this shot, we will call it just with the Genus...specie sp. :D


Ps: can maybe help you the place where I found it ?
It was at about 1900 meters altitude near Maniva mountain (Lombardia, Italy) on Alps. there was a 30 x 80 meters little lake (kinda pond).
It was 15.38 Pm, fresh climate but with sun (17 july)
Probably all this info don't mind with the difference between those two species but it's all I can say about it :)



thank you again

Matteo

Edited by Matteo86photonature on 29-07-2008 07:13

Posted by Susan R Walter on 29-07-2008 13:50
#7

I think if I were you I would call it Aeshna cf subarctica - I am 90% convinced by Cosmin's arguments. :D

Posted by Matteo86photonature on 30-07-2008 07:45
#8

perfect, I renamed it like that just now :)

thank you again!

greetings, Matteo