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Sticker of Spinybacked orb-weaver
Bug card No. 1274 of 1,500

Spinybacked orb-weaver

Gasteracantha cancriformis
Name means: “belly thorn, shaped like a crab”
Eats: Other bugs and small animalsSpidersGardens and meadows8 legsNot an insect, but a bug cousin

The spinybacked orb-weaver is a small spider that looks like a tiny shield with spikes. Its back is white or yellow with black spots, and it has six pointy spines around the edge. It is wider than it is long, a bit like a crab.

Fun fact: spiders are not insects. Insects have six legs, spiders have eight. Everyone calls them bugs anyway!
Lives in
North, Central and South America and the Caribbean, also Hawaii, at woodland edges and in gardens
Length
5 to 9 mm (0.2 to 0.35 in)
Top speed
about 1.1 km/h (0.68 mph)
On foot, estimate
Can it hurt you?
Harmless
What does it eat?
It spins a round web and eats the small flying insects that get stuck in it.
For real!Photo of Spinybacked orb-weaver
Picture by Sam Fraser-Smith from Brisbane, Australia. CC BY 2.0, via Wikimedia Commons.

How big is it?

How long is it?

Spinybacked orb-weaver about 9 mm long (0.35 in)A grain of rice about 6 mm (0.24 in)A toy building brick about 3.2 cm (1.3 in)
small enough to sit on your fingernailas long as 1.5 grains of rice in a rowcould run across a dinner table in 3.3 secondsmoves 34 times its own body length every second

How big is Spinybacked orb-weaver compared to YOU?

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How fast is it?

cool stuff

Fun facts

1

A female is about 5 to 9 millimetres long but 10 to 13 millimetres wide.

2

Its spines can be red or black, depending on the spider.

3

Its daily rhythm is about 19 hours long, not 24 like ours.

4

Males are tiny, only 2 to 3 millimetres long, with short stubby spines.

5

It sometimes lives right next to big colonies of other web-building spiders.

you asked

Most asked questions about Spinybacked orb-weaver

?Why does this spider have spikes?

The six spines on its back are part of its shape. They make it look like a little spiky shield.

?How long does it live?

Less than a year. It hatches, lives through the winter and dies after having babies in spring.

For bug experts

Scientific name
Gasteracantha cancriformis
Named by
Linnaeus, 1758
Group
Spiders
Family
Araneidae
Classification
Arachnida > Araneae > Araneidae
Lives on
North America, South America, Australia and Oceania
Also known as
Spinybacked orbweaver

Where the facts come from

  1. Gasteracantha cancriformis (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 Sam Fraser-Smith from Brisbane, Australia. CC BY 2.0, Wikimedia Commons. The round sticker of this bug is cut from the same 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.

More from the same group: Spiders

Also at home here: Gardens and meadows