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Sticker of Gem moth
Bug card No. 1811 of 4,939

Gem moth

Orthonama obstipata
Eats: PlantsMothsGardens and meadows6 legs

The gem is a small moth that lives almost all over the world. The males are light brown with wavy whitish lines, and the females are much darker, almost black-brown. It is a great flier and can cross wide stretches of open sea.

Lives in
Almost all over the world, even reaching Britain and Iceland
Wingspan
1.8 to 2.1 cm (0.71 to 0.83 in)
Top speed
about 10 km/h (6.2 mph)
Flying, estimate
Can it hurt you?
Harmless
Harmless. It does not bite or sting.
What does it eat?
Its caterpillars eat many low plants, such as bedstraw, bindweed, ragwort, groundsel, docks and knotweed.
For real!Photo of Gem moth
Picture by Ben Sale from UK. CC BY 2.0, via Wikimedia Commons.

How big is it?

How wide are its wings?

Gem moth wings about 2.1 cm tip to tip (0.83 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)
wings as wide as 4 grains of rice in a rowcould fly across a whole football pitch in 38 seconds

How big is Gem moth compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

Its wings are only about 2 centimetres from tip to tip.

2

Male and female look so different that you might think they are two kinds of moth.

3

Both have a small black spot with a white rim on each front wing.

4

It travels so far that it sometimes reaches Iceland.

5

Over the years people described it as new again and again, so it has many old scientific names.

you asked

Most asked questions about Gem moth

?Where does the gem moth live?

Almost everywhere in the world. It is a strong flier that wanders far.

?How can you tell a male gem from a female?

The male is light brown with wavy pale lines. The female is much darker, nearly blackish brown.

For bug experts

Scientific name
Orthonama obstipata
Named by
Fabricius, 1794
Group
Moths
Family
Geometridae
Classification
Insecta > Lepidoptera > Geometridae
Lives on
Europe, Asia, Africa, North America, South America, Australia and Oceania
Also known as
The gem

Where the facts come from

  1. Orthonama obstipata (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 Ben Sale from UK. CC BY 2.0, 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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