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Sticker of Northeastern hammertail
Bug card No. 3015 of 4,939

Northeastern hammertail

Efferia aestuans
Name means: “named for the hammer-shaped tip of the male's tail”
Eats: Other bugs and small animalsFlies and mosquitoesGardens and meadows6 legs

The northeastern hammertail is a robber fly, a fast hunter of the insect world. It sits on a perch and waits, then zooms out to grab flying insects, even ones bigger than itself. It has a bushy moustache and huge eyes.

Lives in
Eastern North America, from Ontario to Florida and New Mexico, in grasslands, wetlands and sandy places
Length
1.4 to 2.8 cm (0.55 to 1.1 in)
Wingspan
3 to 5 cm (1.2 to 2 in)
Top speed
about 15 km/h (9.3 mph)
Flying, estimate
Can it hurt you?
Can bite
It is calm and friendly and often lands on people. It can poke with its sharp beak only if it is grabbed, so just let it sit.
What does it eat?
It catches flies, bees, butterflies, moths, grasshoppers and even dragonflies. Its babies live in sand and eat beetle grubs.
For real!Photo of Northeastern hammertail
Picture by Cody Hough. CC BY-SA 3.0, via Wikimedia Commons.

How big is it?

How long is it?

Northeastern hammertail about 2.8 cm long (1.1 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)A crayon about 9 cm (3.5 in)

How wide are its wings?

Northeastern hammertail wings about 5 cm tip to tip (2 in)A toy building brick about 3.2 cm (1.3 in)A crayon about 9 cm (3.5 in)A banana about 18 cm (7.1 in)
as long as 5 grains of rice in a rowwings as wide as 1.5 toy building brickscould fly across a whole football pitch in 25 secondsmoves 150 times its own body length every second

How big is Northeastern hammertail compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

Its sharp beak works like a straw. It makes its prey go still and turns its insides into a drink.

2

It can turn its head almost all the way round to spot prey and danger.

3

The bristly moustache on its face protects it from kicking prey.

4

Its babies grow up underground in sand dunes and have no wings at all.

5

Sometimes a female carries a smaller male on her back while she keeps hunting.

you asked

Most asked questions about Northeastern hammertail

?Does the hammertail bite?

Only if you grab it. It is calm, often lands on people and is not dangerous.

?What does the hammertail eat?

Other flying insects like flies, bees, moths and even dragonflies.

For bug experts

Scientific name
Efferia aestuans
Named by
Linnaeus, 1763
Group
Flies and mosquitoes
Family
Asilidae
Classification
Insecta > Diptera > Asilidae
Lives on
North America
Also known as
Northern hammertail, Eastern hammertail

Where the facts come from

  1. Efferia aestuans (Wikipedia, CC BY-SA 4.0): what it looks like, where it lives, what it eats, sizes and fun facts, retold in simple words.
  2. Picture by Cody Hough. CC BY-SA 3.0, Wikimedia Commons. The sticker of this bug is drawn from this picture.

If we got something wrong, sorry, we are bug fans, not a science journal. Tell us at [email protected] and we will fix it.

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