Eastern Forktail

Common Name: Eastern Forktail.

Scientific Name: Ischnura Verticalis.

What to look for?  Damselfly, not dragonfly! A damselfly is smaller, has a slimmer body, and will fold their wings along the body when at rest (dragonflies keep wings extended to the side). The Eastern Forktail is lime green on the head, deep sky blue on the tail end and black everywhere in between! There is some black striping on both the head and thorax. Their bulging eyes protrude on the sides of their head, are dark above and greenish below with small green eyespots. They have a very slender, elongated abdomen that is almost entirely black and divided into some nine segments. One of the most distinguishing features is deep sky blue coloring of the last two segments at the tip. The female Eastern Forktail is similar in color to the male, but is bluer on the final abdominal segments. Adult damselflies have two pairs of elaborately veined wings that are the same size and shape. Their six legs are poor for walking but good for perching.

Where can they be found at Carillon Stonegate Pond? The Eastern Forktail will be found here from May to September.  They are mostly found low among vegetation near or at the shore or basking in the sun on walkways.

How big are they? The Eastern Forktail averages approximately 1 ¼ inches in length with the abdomen being one inch. And their wingspan is approximately ¾ of one inch.

What are their flight patterns? In general, damselflies are weak-flying insects. When Eastern Forktails do fly, they are very agile when in flight. They can fly forward, backwards and are also capable of hovering in the air. And they feed and mate while in flight.

How else do they behave? An adult Eastern Forktail may survive for only a few months so feeding and mating behaviors are paramount. Adult males commonly perch on branches or other objects, patrolling their territories, driving away rival males and attempting to mate with females. Damselflies, including the Eastern Forktail, cannot sting; however, when handled, they might try to bite, which will feel like a pinch. Damselflies are extremely beneficial predators and help control populations of harmful insects.

What’s for dinner? Eastern Forktail adults eat small flying insects that they grasp in flight. They hold their legs in a basket shape to capture their prey during flight. During their nymph development stage, they will rest quietly on a submerged plant, then send their extendable, scoop-like jaws outward to snatch and draw in small aquatic animals as they swim or walk near the nymph.

Where do they take up residence? The Eastern Forktail is found from the Midwest to the east coast and from southern Canada to the Gulf states. Eastern Forktails reside in a variety of wetlands, but prefer small well-vegetated ponds.

When and where do they breed and nest? There are three stages in the damselfly life cycle: (1) egg, (2) naiad (the nymph of a damselfly) and (3) adult. Unlike most damselflies, Eastern Forktail females tend to be monogamous, mating only once. A female may fertilize over a thousand eggs using the sperm from a single-male encounter. Eggs are either laid in water, on underwater vegetation, or other water-filled cavities such as in bromeliads. Eggs usually hatch within a few weeks. Once hatched, the naiad has an elongated body, long legs and three leaf-like appendages or gills on its tail. Damselflies live as nymphs for several years and undergo five or more molts as they grow. At the last stage, a naiad crawls out of the water and clings to a plant, drying its skin. After a few minutes basking in the sun, the outer skin splits open at the head and the adult damselfly emerges. In a matter of days, the adult Eastern Forktail is sexually mature and returns to an area near water to breed – starting the cycle over.

Where do they migrate? No.

What is their conservation status? No.

Do they make any interesting sounds? No.

Interesting Facts About the Eastern Forktail (and damselflies compared dragonflies):

  • The name "forktail" comes from tiny projections off the tip of males' abdomens, which help to identify the species.

  • Dragonflies and damselflies, like cockroaches, are two of the oldest insect groups. During prehistoric times, they were supposedly as big as hawks.

  • There are four details that distinguish a dragonfly from a damselfly: (1) eyes, (2) body shape and size, (3) wing shape and size, and (4) position of the wings at rest.

    •  (1) Eyes: Dragonfly are broadly rounded and lie mostly flat against the head; whereas, Damselfly are largely spherical and protrude off the sides of the head.

    • (2) Body Shape and Size: Dragonfly has broader thorax than abdomen; whereas, Damselfly have narrower thorax and abdomen with each the same width; Dragonfly is generally larger than Damselfly.

    • (3) Wing Shape and Size: Dragonfly has forewings and hindwings of different shapes and sizes; whereas, Damselfly has forewings and hindwings of same shapes and sizes.

    • (4) Position of the Wings at Rest: Dragonfly rests wings flat or parallel to the ground and to the side of its body; whereas, Damselfly rests its wings straight up and pressed together over the top of its body.

For more information on the Eastern Forktail and sources of information used in this blog (these are the several of the sources that I am using to learn as I blog), please visit Odonata Central, The Dragonfly Woman, Iowa State University's Guide, University of California – Berkeley, and Wisconsin Odonata Survey.

The Carillon at Stonegate community is very fortunate to have a variety of wetland, forest and prairie environments conducive to a variety of birds and other wildlife, insects and plants. Our community and the Kane County Forest Preserve do an exceptional job in maintaining this natural environment – both for the benefit of the birds and wildlife and for our residents to enjoy.

 

Take a hike and see what you can find – and identify!