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Sticker of Sombre goldenring
Bug card No. 3980 of 4,939

Sombre goldenring

Thecagaster bidentata
Eats: Other bugs and small animalsDragonflies and damselfliesPonds, rivers and shores6 legs

The sombre goldenring is a big dragonfly with a black body and bright yellow rings. It lives near cold springs high up in the mountains. Its babies hide at the bottom of the water for years before they can fly.

Lives in
Central and Southern Europe, by mountain springs and streams
Length
8 cm (3.1 in)
Wingspan
10 cm (3.9 in)
Top speed
about 46 km/h (29 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. It does not sting people. It only hunts small insects.
What does it eat?
Like all dragonflies, it hunts other insects. Its larvae hunt in the water, and sometimes even climb out at night to catch small creatures on the ground.
For real!Photo of Sombre goldenring
Picture by Charles J. Sharp. CC BY-SA 4.0, via Wikimedia Commons.

How big is it?

How long is it?

Sombre goldenring about 8 cm long (3.1 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)

How wide are its wings?

Sombre goldenring wings about 10 cm tip to tip (3.9 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 2.5 toy building bricks in a rowwings as wide as your handcould fly across a whole football pitch in 8.2 secondsmoves 160 times its own body length every second

How big is Sombre goldenring compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

Its larvae live in the water for three to five years before they turn into flying dragonflies.

2

If the winter is so cold that the water freezes, the larvae grow even more slowly.

3

The mums lay their eggs in the upper parts of mountain streams in May and June.

4

Its numbers are going down, because dry summers make the mountain springs dry up.

you asked

Most asked questions about Sombre goldenring

?How big is the sombre goldenring?

Its body is about 8 centimetres long and its wings are about 10 centimetres from tip to tip.

?Where does the sombre goldenring live?

In Central and Southern Europe, around springs in the mountains. It lives as far south as the island of Sicily.

For bug experts

Scientific name
Thecagaster bidentata
Group
Dragonflies and damselflies
Family
Cordulegastridae
Classification
Insecta > Odonata > Cordulegastridae
Lives on
Europe
Also known as
Two-toothed goldenring

Where the facts come from

  1. Thecagaster bidentata (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 Charles J. Sharp. CC BY-SA 4.0, 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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