Emeralds
 To learn more about the groups (genera) of Emeralds, click on the links at the right
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This family is named for the brilliant green eyes developed by many species. Most
Emeralds are small to medium sized, averaging between 1.5 - 3" (42-52
mm) in length. This is a very variable family. Most have a dark thorax and abdomen
that may develop green or bronze iridescence. Spots may be present on the thorax
and abdomen, in many species these fade with age.
The abdomen may be long and slender, but in some groups is quite stout. In
many species the shape of the abdomen can give important clues to the identity.
The wings of Emeralds are generally clear but may develop an amber tint. In groups
like the Baskettails, dark basal wing patches or spots may be present. Females are
similar to the males but usually have duller eyes and a more robust abdomen.
Some Emeralds can be very difficult to find, mainly because they breed locally in
bogs or other difficult habitat. Others can be abundant, and commonly found
along almost any pond or lake shore. Emeralds are strong erratic flyers that fly
for very brief period of time, and for a somewhat short flight season. Many members
of the group occur farther north or at higher elevations than most other dragonflies.
Males can often be seen patrolling over breeding sites along the waters edge searching
for a receptive female. After males and females mate, the female flies alone
to lay her eggs. Emeralds show a wide variety of ovipositing behaviors.
Some species oviposit by flying low over the water tapping the tip of the abdomen
on the water surface releasing eggs. Others lay eggs in mud or shallow
water by inserting their well-developed ovipositors into the substrate. Female
Baskettails have their own method; the female carries the eggs in a rolled-up string
ball under her abdomen, when a suitable ovipositing site is found, she releases
the eggs into the water where the chain unwinds.
Emerald larvae are "sprawlers", they lie on the sand or soft muck in woodland
stream bottoms waiting to ambush prey. They have long spines down the back
and on the tip of their abdomens. They have a wedge shaped head and long legs.
Emerald larvae are generally black in coloration and hairy. To complicate matters,
there are some larvae to this family that are climbers, making their way among vegetation
looking for prey. These particular larvae appear smooth and patterned with brown
and greens.
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