Aeshna subarctica and/or crenata?

Selkärangattomat eläimet Sudenkorennot
1

Hello.
Around july 21st we stayed in Kangasniemi.
There was a beautiful small forest lake with spaghnum mosses nearby.
Around this lake I found several Aeshna. But I’m not sure which ones.
Where I live only juncea is present so I have never seen crenata, serrata and subarctica.

I have photographs of 3 individuals (coded yellow, blue and green).
Of the most blue individual I also have a (not great) photo of the tip.
They are probably all subarctica. But I’m not sure about that.

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The 3 individuals from the side:

IMG_4419
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And from the back:

IMG_4418
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Are these 3 the same species?
Which species? What do you use as a defining criterium?
I can upload larger photos if needed.
Thanks in advance

2

Hey.
Yes, all three individuals are Aeshna subarctica.

3

Kiitos!

4

Aeshna subarctica is rather similar to Aeshna juncea, but for example following differences between these species you can see:

  1. Leading edge of wings more brown than yellow.
  2. Appears darker and more uniform than A. juncea
  3. Three typical spots between the bands on side of thorax
  4. The black line along the facial suture is of constant thickness or even widens at the eyes (however not always), while in A. juncea it narrows at the sides