Wednesday, July 31, 2013

Painted Skimmer (Libellula semifasciata)

Last night I was helping a friend sort and identify the odonate images on his HDD when I came across several striking photos of a female Painted Skimmer (Libellula semifasciata). The photo below was taken by Jason King on June 3rd, 2013, about 1.5 km west of Tweed, close to the location where we later discovered a colony of rare Juniper Hairstreaks.

I mistakenly thought the male dragonfly in the next image, taken in 2011, might be a Painted Skimmer, but it's actually an uncommon color variant of a Four-spotted Skimmer – Libellula quadrimaculata praenubila.

In addition to the differences in the wing and abdominal markings, the Painted Skimmer has yellow pterostigmata bordered in black. I would say the specimen in Jason's photo has some yellow in its pterostigmata with strong dark edging. however, they are definitely not completely black as in my Four-spotted Skimmer. Furthermore, according to accounts I've found on the 'net (for example, at Urban Dragon Hunters), L. semifasciata has fewer forewing crossveins than L. quadrimaculata. So barring further evidence to the contrary the dragonfly in Jason's photo is indeed a Painted Skimmer.

I had been forewarned as far back as June 2011 by a reliable authority to keep an eye out for this species in Hastings County, as it had been sighted regularly in Presqu'ile Provincial Park. And I've been recently informed that Libellula semifasciata has been recorded as far north as the Bruce Peninsula (2008 – 09) and Algonquin Park (2011).

It's now late July – two months since Jason encountered the Painted Skimmer. Assuming they emerge early in the season like their cousins, I doubt if they are still flying, and I'll have to wait until next year to acquire my own photos of this attractive dragonfly.