Monday, June 8, 2009

Ebony Jewelwings and GBSF

On a recent foray into the wilds of Adams County, I came across a small stream flowing through the limestone glades. The most conspicuous insect occupying the waterway and vicinity were one of our most beautiful damselflies, the Ebony Jewelwing, Calopteryx maculata.

You've probably seen jewelwings before. They are very evident and easily identified. Their flight appears languid and fluttery, but that's deceptive. Like other dragonflies, jewelwings are quite speedy, especially if the situation calls for it. This one is a female, as can be told by the bright white stigmas, or spots on the corner of the leading edge of the wing.

We didn't encounter any of the females near the stream. All were back in the forest on either side, and not within a few hundred yards of the water. I suspect this might have been because of the testosterone-charged males, which don't stray far from the creek banks. If one of the females put in an appearance, these guys would be all over her.

This is the male, with solid coal-black wings. Their bodies are stunning in coloration; shiny iridescent green, turning to a bright blue depending on how the light strikes the insect. The small Adams County stream was full of male jewelwings, making sorties out over the water, briefly perching on overhanging vegetation, and duking it out with each other.


I caught this video of one of the males engaging in an almost hypnotic wing-flashing display; a kaleidoscope-like effect that is quite fetching. I think its purpose is to send a message to other males - "back off - this is my turf!" Note the Wood Thrush singing in the background.

Several of the stunning Golden-backed Snipe Flies (GBSF), Chrysopilus thoracicus, were also encountered in this same forest. These flies of early summer are striking in the extreme. Like many small insects, they'd be easy to miss, but if one pays careful attention you'll notice one sooner or later. I believe this one is a male, with a narrower tapered abdomen.

Top down on a GBSF. It's as if their napes were made of brushed golden silk. Like so many insects, precious little seems to be known about this species and its life cycle. If I knew more about Golden-backed Snipe Flies other than their name, I'd pitch it out there. But knowing the name and identity is a start, I suppose.


nanci said...

I saw Ebony Jewelwings for the first time about a year ago in Swan Creek park.They are gorgeous! Although I observed that their bodies were various separate metallic colors- the blue, green, and even a reddish or copper color. Do they inhabit areas around water, like dragonflies? I wonder about that, since I have only seen them in the park, and not around my garden or watergarden, only a distance of a 5 minute walk away! Thanks for the photos.

Jim McCormac said...

Hi Nanci,

Yes, jewelwings frequent creeks, streams and sometimes ponds and lakes. They are a type of damselfly, closely allied with dragonflies. Real showstoppers, these beasts, and that wing-flash behavior os very cool.


donaldthebirder said...

Ebony Jewelwings are awesome bugs, I blogged about them myself last year. Did not see them do the wing flash thing though.

Heather said...

Nice bug shots and commentary. I'll soon be posting about some of the insects that we saw during our last few hours at the Wilds, and I expect I'll be needing some correction on the IDs. I'm not too good with dragons and damsels yet, nor butterflies or frogs, but all in good time.

dAwN said...

those jewelwings are beautiful ..cant say I have ever seen them..I will be on the lookout now..
The video was a great bonus!

Anonymous said...

I had a similar experience in my back yard, and also had those awesome golden-backed snipeflies! they are super cool, that gold is shiny. - Ben Warner