Dragonfly: Subarctic Darner from NA

[NikonUser]

Erland posted some nice field shots of mating Subarctic Darners
HERE
and noted that A. subarctica also occurs in NA.

The singular most useful feature for identifying NA Darners are the thoracic stripes. In NA the thoracic stripes of Subarctic males are rather narrow and bent forward on the upper half and with 2 yellow spots between the anterior and posterior stripes:

In Erland's top photo the stripes appear to be wider than those of NA subarctica and look a bit like the NA Sedge Darner Aeshna juncea, which unfortunately I have yet to see.

EDIT: title changed

[beetleman]

An excellent image NikonUser. It is a shame these insects do not keep their color once preserved.

[NikonUser]

Thanks Doug.
The colours do keep reasonably well if you degrease/dehydrate fresh specimens with a couple of changes of acetone.
Today the colour fading in preserved material is not that much of a problem as it is easy now to get excellent colour photos of live odes. I do keep a small reference collection of specimens plus colour photos (prints) and the digital files of all the live species I can get my hands on.
Before digital, getting colour photo's was far less convenient.

[Erland R.N.]

I've never seen a detail picture of a North American A. subarctica, so this is very interesting for me. The only two Darners (Hawkers by us Europeans) shared between North America and Europe is A. subarctica and A. juncea.

In Europe A. subarctica is very variable, and the one I showed are what could be called a brigth type, with a fairly large stripe between the two main on the thorax. In many European books the species is represented much like your shown, at least not with a big third stripe.

The best way to distinguish the two (in Europe but must be true for NA too) is that A. juncea has a yellow spot surrounded by black behind the head, while A. subarctica appears all black, because the spot is nearly black too.

Another thing is that in front of the two main stripes, A. subarctica has a faint stripe in front of the suture line (and just in front of the first main stripe).

Here is a link to a forum thread on a Danish nature site, where "everybody" records their observationsof all kind of animals in Denmark:

http://www.fugleognatur.dk/forum/show_m ... ForumID=23

All but the first picture there is taken by me.

At the top is a male A. subarctica.

Then a A. subarctica in flight

Then a female A. subarctica (bottom) and A. juncea (top) where the yellow spot behind eye is seen.

Finally some details on a female A. subarctica pointing out differences between the two species (probably does not make sence for non-danish readers).

The European A. subarctica are considered a different subspecies than the nominal NA one.

Erland