Blue dasher vs Familiar bluet
These two are easy to mix up. Here's how to tell a blue dasher from a familiar bluet, and whether either one bites or stings.
Blue dasher
Pachydiplax longipennis
Familiar bluet
Enallagma civile
≠The key differences
A dragonfly rather than a damselfly: larger, with broader body and wings held open at rest; blue dasher is bulkier and perches differently.
⚖︎Side by side
| Blue dasher | Familiar bluet | |
|---|---|---|
| To humans | Non-toxic | Non-toxic |
| Size | Length about 28-45 mm; wingspan about 50-70 mm | About 29-39 mm body length |
| Colours | Powder blue, Dark brown/black, Yellow-green, Clear wings | Sky blue, Black, Tan, White (underside markings) |
| Family | Libellulidae | Coenagrionidae |
| Habitat | Still or slow freshwater: ponds, marshes, ditches, lake margins and occasionally slow streams with emergent vegetation | Ponds, lakes, marshes and slow-moving streams with standing vegetation and open sunny perches |
| Range | Widespread in the United States and southern Canada, common south into Mexico and parts of Central America; most abundant in lowland and disturbed wetlands | Widespread across much of North America, from southern Canada through the United States and Mexico into Central America and the Caribbean |
| Active | Active from late spring through early autumn (peak in summer); diurnal, most active in warm, sunny weather | Spring through late summer (varies by latitude); most active in warm daylight hours |
| Pest? | No | No |
🔍How to spot a blue dasher
- Males: powder-blue abdomen with a black tip, striped dark thorax, white face and metallic green eyes
- Females and young males: brown-and-yellow striped thorax and dark abdomen with yellow dashes
- Perches on plant stems or bare ground with abdomen slightly raised; wings clear with small dark pterostigma
🔍How to spot a familiar bluet
- Small damselfly with slim body and wings held together above the body when at rest
- Male: bright sky-blue with black stripes on the thorax, black markings on the middle abdominal segments and an almost all-blue abdomen tip
- Female: variable — blue form resembles males; common tan form is brownish with darker markings
- Found perched on emergent vegetation at ponds, lakes and slow streams; size about 29-39 mm
?Frequently asked questions
What is the difference between a blue dasher and a familiar bluet?
A dragonfly rather than a damselfly: larger, with broader body and wings held open at rest; blue dasher is bulkier and perches differently.
Is a blue dasher or a familiar bluet more dangerous?
Blue dasher: Non-toxic. Familiar bluet: Non-toxic. Blue dashers do not bite people except in extreme, rare handling situations; any bite would be a mild pinch only. Familiar bluets do not sting and are not poisonous.
Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.