In the two weeks we have been gone, our Minnesota backyard has transformed from early spring to early summer. The perennials have shot up at least two feet, and there are quite a few insects flitting about. Today, the damselflies were almost as thick as the mosquitoes, as they cruised from leaf to leaf.
Male and female Northern Bluets (I am guessing) congregated like hands on a clock face on the new leafy growth of the goldenrod stems.
Male Northern Bluets are easily recognized by their striking blue patterned bodies. Fortunately, Minnesota is home to only three bluet damselfly species, making ID a little easier.
Female Northern Bluet damselflies lack the blue coloration on eyes, thorax, and abdomen, as well as the signature blue spot at the tip of the abdomen. Notice how the color of the post-ocular spots (behind the eyes) matches the color of the thoracic stripes on both the male and female.
This is a truly wide-ranging species, found throughout the northern hemisphere in North America, Europe, and Asia, but ranging as far south as India and Mexico. They appear early in the spring and are active until late summer, probably one of the most common damselflies seen.
Damselfly ID guides say that the Northern Bluet is highly variable in its blue color pattern. But this must be another species, and its color pattern doesn’t match any of the MN damselfly species. Help me out here, if you know what this is.
Eastern Forktail Damselfly males were found right alongside the Bluets. Their distinctive green and black thoracic stripes and bright blue spot at the end of the abdomen, as well as slightly larger size, distinguished them from the more common bluets.
Eastern Forktail damselflies are common throughout the north and eastern U.S., ranging as far south and west as Oklahoma. Thoracic stripes in females may be yellow-green to yellow-orange, but I didn’t see any of these among the Goldenrod leaves, so perhaps they have not emerged yet. Females begin mating within a few days of emerging, and lay eggs within a few hours of mating. Unlike most Odonates (dragonflies and damselflies), Eastern Forktails are monogamous, and all of the female’s eggs are fertilized by just one encounter with a male.
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