Excerpts from Jim Conrad's
from the June 24, 2012 Newsletter issued from the woods of the Loess Hill Region a few miles east of Natchez, Mississippi, USA
EBONY JEWELWING DAMSELFLY
Deep in nearby Homochitto National Forest's swamps where Baldcypresses and their knees rise from black water, things are quiet, almost somber, except for the black-winged damselflies. Nearly always at least one or two can be seen darting about snatching mosquitoes from mid air or fluttering from plant to plant. Often those without little white dots at the tips of their wings (the males) flirt with those bearing white dots, and sometimes the dotteds and un-dotteds couple, forming heart-shaped unions as they mate. That's an un-dotted male, his slender, metallic-blue body shining in the swamp's dim light, above.
Volunteer identifier Bea in Ontario recognized the species at sight because it's a common species in most of eastern and central North America, including Bea's Ontario. It's the Ebony Jewelwing, CALOPTERYX MACULATA. The technical name, or binomial, practically describes the species -- calo-pteryx in classical Greek meaning "beautiful-wing," and maculata referring to the white spots.
Despite looking so dainty, Ebony Jewelwings are voracious predators. During their aquatic larval stage, when they are known as naiads and vaguely look like wingless, leggy mosquitoes, they prey on many kinds of tiny aquatic organisms, including rotifers, copepods, hydras, water fleas and aquatic worms. When the naiads are ready to metamorphose into adults they climb to the water's edge, their external skeleton, or exoskeleton, splits open and the winged adult emerges. Then the winged adult preys not only on mosquitoes but also gnats, crane flies, aphids and other small invertebrates. In turn, birds such as flycatchers, as well as bats, frogs and many other insect eaters prey on them. So heavily involved in "eating and being eaten," Ebony Jewelwings are an important nexus in the swamp's web of life.