Dragonflies are such iconic insects that it’s easy to assume that all dragonflies are the same, especially since they share the same distinctive body and wing shape. However, this is not the case. Dragonflies evolved over 320 million years into a large number of species that display differences in color, abdominal shape, eye morphology, and behavior.
There are approximately 450 different types of dragonflies in the United States, classified in seven families. The common family names are: darners, spiketails, clubtails, skimmers, emeralds, cruisers, and petaltails. The families vary by body shape, perching position, and hunting method.
Dragonflies are easy to identify as “dragonflies” thanks to their distinctive body and wing shape. But there is great value in going beyond simple identification and learning about the different types of dragonflies that share our natural world, if only because these insects are so beautiful, harmless, and easy to observe. Read on to learn about the different types of dragonflies found in the United States.
Darner dragonflies (family Aeshnidae)
Darner dragonflies are medium to large dragonflies. In the southeastern United States, darners range in size between 2.4-3.7 inches in body length (6.1-9.4 cm).
Species in this family are strong fliers; they can often be found far from water but are still associated with lakes and marshes. Darners spend most of their time flying or hovering. They course back and forth through an area and spot, catch and often eat prey in flight. When they do perch, they prefer to hang vertically from vegetation unless the temperatures are cool, at which time they will perch horizontally on flat surfaces in the sun.
Besides being strong fliers, darner dragonflies are strong insects in general. They attack larger prey than some other dragonflies. Their legs are so strong that males sometimes injure females by grasping them too tightly during mating (Abbott 2015).
Worldwide, genus Gynacantha, or “two-spined darners”, has the most species but only two of these are found in the United States (Abbott 2015). In North America, the largest genus is genus Aeshna, known as “mosaic darners”, with fifteen species, while the most widely distributed and commonly seen darners are usually the “green darners” within genus Anax.
Ways to identify darner dragonflies:
- Long, slender abdomens that reminded early people of sewing needles used for darning – thus their common name.
- Usually clear or tinted wings without colored bands or patches.
- Only species of flier that has blue coloration on their bodies (Paulson 2012).
- Brightly colored, boldly patterned bodies with two thoracic side stripes and abdominal spots.
- Very large eyes that meet in the middle of the tops of their heads.
Darner dragonfly genera found in the United States include:
- mosaic darners (Aeshna)
- springtime darners (Basiaeschna)
- swamp darners (Epiaeschna)
- spotted darners (Boyeria)
- pilot darners (Coryphaeschna)
- pygmy darners (Gomphaeschna)
- two-spined darners (Gynacantha)
- cyrano darners (Nasiaeschna)
- neotropical darners (Rhionaeschna)
- three-spined darners (Triacanthagyna)
Petaltail dragonflies (Family Petaluridae)
Petaltails are large dragonflies. The gray petaltail (Tacopteryx thoreyi) is the only petaltail found in the United States and is 2.8-3.3 in (7.1-8.4 cm) in body length.
Gray petaltails are seen in the United States from April to July but are only common in the woods around marshes and seeps. They fly quickly and in straight lines from perch to perch. Unlike darners, petaltails hunt by lurking; they perch motionless in a spot with a wide visual field of view until they spot prey then zoom out to intercept. Sometimes, they will make slow, figure-eight patterns around clearings to catch small flying insects (Paulson 2012).
Gray petaltails sleep in deciduous forests and perch vertically on flat surfaces, especially tree trunks and rocks where their dull gray and black coloration camouflages them very well despite their size. They may be attracted to light colored clothing and sometimes land on people moving slowly through their area.
Ways to identify petaltail dragonflies:
- Males have appendages on the tips of their abdomens that resemble the petals of flowers – thus their common name.
- Clear wings.
- Dull gray and black bodies that blend easily into tree bark.
- Heavy, robust bodies with single black thoracic side stripes.
- Widely spaced brown eyes that do not meet on the tops of their heads.
Petaltail dragonfly genera in the United States include:
- gray petaltails (Tachopteryx)
Clubtail dragonflies (Family Gomphidae)
In the southeastern United States, clubtail dragonflies range in size from 1.9-3.5 inches (4.8-8.9 cm).
The easiest way to identify a clubtail dragonfly is by observing the presence of an abdominal club. While some cruiser and clubskimmer dragonflies also have clubbed abdomens, this trait is rare outside of family Gomphidae (clubtail dragonflies are sometimes referred to as “gomphids”).
Both sexes of clubtail dragonflies have clubbed abdomens, although those of males tend to be larger and more obvious. Females carry the organs required to lay eggs in their abdomens, which make their abdomens slightly thicker along their entire lengths and their terminal clubs seem smaller.
Clubtails have short flight seasons so appear and disappear within a few weeks despite many species being locally abundant in their habitats during this time. They spend a lot of time at rest, usually perched horizontally on the ground, leaves, or on twigs, and hunt from their perches.
An interesting trait that clubtails share only with some species of skimmer dragonflies is “obelisking”. When perched out in the open, clubtails sometimes tilt their abdomens vertically so it points to the sun and sky. While not always the case – some larger males and females who are about to lay eggs may curl their abdomens toward the ground rather than obelisk with abdomens held out straight – clubtails often assume this position and it can be a good starting point for field identification.
Ways to identify clubtail dragonflies:
- Bulbous, enlarged abdominal tips that reminded early people of weapons like clubs – thus their common name.
- Clear wings
- Patterned green or yellow and brown or black bodies
- Multiple thoracic stripes
- Small, separated blue or green eyes
- “Obelisk” when perch in the open
Clubtail genera found in the United States include:
- greater forcepstails (Aphylla)
- pond clubtails (Arigomphus)
- spinylegs (Dromogomphus)
- ringtails (Erpetogomphus)
- common clubtains (Gomphus)
- dragonhunters (Hagenius)
- lesser forcepstails (Phyllocycla)
- leaftails (Phyllogomphoides)
- sanddragons (Progomphus)
- hanging clubtails (Stylurus)
Spiketail dragonflies (family Cordulegastridae)
In the southeastern United States, spiketail dragonflies range in size from 2.5-3.4 inches (6.4-8.7 cm) in body length.
Spiketail dragonflies perch vertically and usually out in the open where they can get a good view of their surroundings. When they fly, they fly low to the ground through sunny clearings and seem to be fond of bees and wasps as prey (Paulson 2012).
Most spiketail species are found in Eurasia, with only about 10 species found in the United States, all of which belong to the same genus Cordulegaster.
Ways to identify spiketail dragonflies:
- Females have thin, spiky ovipositors (egg-laying structure) on the ends of their abdomens – thus their common name.
- Clear wings.
- Black or brown bodies with yellow thoracic stripes and abdominal patterns.
- Blue or green eyes; either slightly separated or meeting on the tops of their heads in only one spot.
Spiketail dragonfly genera seen in the United States include:
- spiketails (Cordulegaster)
Cruiser dragonflies (family Macromiidae)
In the southeastern United States, cruiser dragonflies range in size from 2.6-3.5 inches (6.6-8.9 cm) in body length.
Cruisers are often found in the same areas as darner dragonflies, which can make field identification difficult because both have large eyes that meet at the top of the heads. But some male cruiser species have clubbed abdomens, which darners lack. This, along with cruisers’ comparatively inconspicuous coloring and single thoracic stripe, can help differentiate them.
Cruisers have long legs and like to perch vertically, often around eye level to humans so can be easy to spot. They fly up and down the lengths of streams and rivers and along lake shores, but may also travel far from water.
Ways to identify cruiser dragonflies:
- Spend most of their time in flight cruising great distances for prey and mates – thus their common name.
- Clear wings.
- Dark brown or black bodies with single, pale strip on each side of the thorax that runs under thorax from one side of the insect’s body to the other and spotted or ringed abdominal patterns.
- Large eyes that meet along the margins on the tops of their heads.
Cruiser dragonfly genera seen in the United States include:
- brown cruisers (Didymops)
- river cruisers (Macromia)
Emerald dragonflies (family Corduliidae)
In the southeastern United States, emerald dragonflies range in size from 2.3-2.9 inches (5.8-7.4 cm) in body length.
Emerald dragonflies are medium-sized, slim, and found around fast flowing streams. They are active mostly in the early morning and late evening so are not as easy to spot as those dragonflies that fly throughout the day. When they perch, emeralds perch between 45 and 90 degree angles but are mostly “fliers” and spend their active periods hunting on the wing.
Ways to identify emerald dragonflies:
- Named for their brilliant green eyes (immature emeralds have reddish-brown eyes).
- Brown-blotched or clear wings.
- Dark-colored bodies covered with yellowish hairs that create a haze around them when backlit. Bodies are sometimes metallic.
- Eyes meet at the top of their heads along their margins.
Emerald dragonfly genera seen in the United States include:
- baskettails (Epitheca)
- sundragons (Helocudulia)
- shadowdragons (Neurocordulia)
- emeralds (Somatochlora)
- boghaunters (Williamsonia)
- common emeralds (Cordulia)
- little emeralds (Dorocordulia)
- striped emeralds (Somatochlora)
Skimmer dragonflies (family Libellulidae)
In the southeastern United States, skimmer dragonflies range in size from 0.8-2.5 inches (2-6.4 cm) in body length.
Skimmers are the largest family of dragonflies, with over 1000 species worldwide, and 100 found in North America. They are commonly spotted around ponds and lakes and hunt from perches by spotting their prey from a distance, then flying to intercept.
Like clubtails, some skimmers obelisk when perching but with so many species in the family, perching behavior varies widely. Some skimmers are “hang perchers”, meaning they hang onto the perch from below and dangle (Abbott 2015).
Ways to identify skimmer dragonflies:
- Patterned wings with wide variety of species-specific colors and patterns.
- Boldly colored bodies.
- Abdomens are shorter and stouter than other dragonfly families.
- Mature males develop “pruinescence” (bluish or whitish coloration created within the exoskeleton).
- Large eyes that meet on the tops of their heads.
Skimmer dragonfly genera seen in the United States include:
- tropical pennants (Brachymesia)
- clubskimmers (Brechmorhoga) (have clubbed abdomens)
- convict skimmers (Cannaphila)
- small pennants (Celithemis)
- set wings (Dythemis)
- pondhawks (Erythemis)
- dragonlets (Erythrodiplax)
- metallic pennants (Idiataphe)
- corporals (Ladona)
- king skimmers (Libellula)
- marl pennants (Macrodiplax)
- sylphs (Macrothemis)
- hyacinth gliders (Miathyria)
- speckled dashers (Micrathyria)
- tropical king skimmers (Orthemis)
- blue dasher (Pachydiplax)
- rock skimmers (Paltothemis)
- rainpool gliders (Pantala)
- amberwings (Perithemis)
- scarlet-tails (Planiplax)
- whitetails (Plathemis)
- filigree skimmers (Pseudoleon)
- meadowhawks (Sympetrum)
- pasture gliders (Tauriphila)
- evening skimmers (Tholymis)
- saddlebags (Tramea)
Conclusion
Dragonflies are some of the most exciting insects to watch and it can be very rewarding to understand that they are so much more diverse than their basic body and wing design might indicate. Learning about the subtle differences between the families can fill dull, dragonfly-free winter days.
Related Now I Wonder posts:
For more about dragonflies and other insects in order Odonata, check out these other Now I Wonder posts:
- Is a dragonfly a fly?
- Can dragonflies walk?
- What do dragonflies do at night?
- What is the difference between a dragonfly and a damselfly?
- Dragonflies vs. Butterflies Part 1: First Comes Form
- Dragonflies vs. Butterflies Part 2: Second Comes Function
For information about insects in general, check out these other Now I Wonder posts:
- Do insects ever eat spiders? Part 1: Attacks from the air
- Do insects ever eat spiders? Part 2: Attacks from the ground
- Do insects have blood?
References
Abbott, John C.. 2015. Dragonflies of Texas : A Field Guide. New York: University of Texas Press.
Paulson, Dennis. 2012. Dragonflies and Damselflies of the East. Princeton: Princeton University Press.