Monday, August 20, 2018

Lilypad Forktails appearing everywhere!

I had a meeting yesterday morning with MaLisa Spring, coordinator of the Ohio Dragonfly Survey, and entomologist Dave McShaffrey of Marietta College, coauthor of the book The Dragonflies and Damselflies of Ohio. We convened at a beautiful park just south of Lancaster known as Alley Park. There is lots of interesting habitat in the vicinity, and we hoped to get afield for a bit following our meeting and search for dragonflies.

The weather put somewhat of a damper on field plans, with intermittent mild showers keeping the dragons largely under wraps. These insects are creatures of the sun, and magically disappear when the sun fades. Fortunately, there were periods of bright overcast and no rain and at such points we had some success.

A prince baskettail, Epitheca princeps, rockets along the shoreline of Lake Loretta in Alley Park. Both Dave and I expended scads of pixels and collectively hundreds of shots trying to photographically nail this animal. This was my only decent shot. There was also a river cruiser in the genus Macromia making occasional passes but we couldn't get that one. These species are FAR more often seen on the wing and finding a perched one is rare. Thus, the need for wing-shooting. A record for the Ohio Dragonfly Survey requires an identifiable photograph. CLICK HERE for instructions on how to submit records, and we would love to have your reports!

As an aside, here is the equipment and settings that I used to make this shot. Canon 5D IV and Canon 300mm f/4 lens, in aperture priority mode at f/4.5, ISO 320, 1/1600, in AI Servo mode with single focus point active. These are generally pretty good settings to try and bag a flying dragon. The main problem is locking focus on the rapidly darting insects.

After finding several species at Lake Loretta, we moved a bit to the south, to a pond that none of us had visited before. Google Earth gives us the overview above. The pond is heavily fringed with growths of fragrant water-lily, Nymphaea odorata, and this aquatic species shows up edging the shoreline in the photo above.

A male eastern pondhawk, Erythemis simplicicollis, rests on a lilypad near the beautiful flower of a fragrant pond-lily. The presence of an abundance of this floating-leaved plant put us on alert for the presence of a coveted species of damselfly.

A number of species of dragonflies and damselflies, especially the latter, habitually frequent the floating leaves of water plants. This is an orange bluet, Enallagma signatum, resting atop the leaf of long-leaved pondweed, Potamogeton nodosus. Our hoped for target species can resemble this bluet, but would likely not choose the pondweed as a rest stop.

Bingo! Within a minute or two of arriving at the pond, we had it - lilypad forktail, Ischnura kellicotti! This is an orange form female, and note her similarity to the orange bluet in the previous photo. There are a number of differences upon inspection, but two obvious ones are the huge orange post-ocular spots (the big dots behind the eyes), and the highly distinctive posture of drooping the tip of the abdomen down to touch the leaf surface. It's like that abdomen tip is a counterweight, pulling her head and forelegs off the leaf.

Also, the forktail is at rest on a fragrant pond-lily leaf - a plant with which it apparently shares an incredibly intimate association. We probably saw a few dozen forktails here, and I don't think any of us saw one perched on anything other than a pond-lily.

Here's an adult male lilypad forktail, looking quite different from the orange-form female in its coat of blue. Same giant post-ocular spots and drooping abdomen tip, though. This animal was photographed at another spot a few miles way; a small lake also covered with pond-lilies. It too was loaded with forktails. Both of these sites were new populations, and represented a new Fairfield County record of this state-endangered species.

When Dave McShaffrey and his coauthor Bob Glotzhober wrote the aforementioned book The Dragonflies and Damselflies of Ohio, published in 2002, they only knew of one site for lilypad forktail, Mud Lake in Williams County in the extreme northwest corner of the state. Dwight Moody found them there in 1992, and until very recently that remained the only known population. Within the last decade, other populations began to turn up and the number of new finds is picking up steam. At least ten counties have been added to its Ohio distribution and lilypad forktails are certainly awaiting discovery in many other locales.

The key to finding them is locating extensive stands of fragrant water-lily. Then carefully search - binoculars are very helpful! - the surfaces of the pond-lily leaves for resting forktails. These bugs are tiny, and can easily be overlooked but once one has the search image they're pretty easy to spot.

Why are lilypad forktails seemingly expanding their range? I don't know. I'm convinced that they are, though. I don't see any way that all of these new populations were overlooked for all these years, especially as some sites are well known, well studied, and heavily visited. This species is primarily southern, occurring along the Atlantic and Gulf coastal plains with scattered inland populations. Ohio is near its northern limits, at least of the inland sites. It may be that steadily rising mean averages temperatures is allowing them to push ever northward.

If you encounter patches of fragrant water-lily, keep a sharp eye out for these little damselflies resting atop the leaves. If you find any, please alert the Ohio Dragonfly Survey. We'd be appreciative of any and all dragon and damsel records, too.


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