Swamp crab spider
The swamp crab spider is a small brown spider that walks sideways like a crab. It does not build a web. Instead it sits very still on low plants in damp places and waits for a bug to come close.
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Fun facts
The girls are much bigger than the boys. Boys are 3 to 4 millimetres long, girls up to 8 millimetres.
The boys are darker and have black parts on their first two pairs of legs.
The mother guards her egg sac, usually near the top of a tall plant.
Before mating, the boy strokes the girl's legs and ties her down with silk.
Most asked questions about Swamp crab spider
?Why is it called a crab spider?
Because it holds its legs out to the sides and can walk sideways like a crab.
For bug experts
- Scientific name
- Xysticus ulmi
- Named by
- Hahn, 1831
- Group
- Spiders
- Family
- Thomisidae
- Classification
- Arachnida > Araneae > Thomisidae
- Lives on
- Europe
Where the facts come from
- Xysticus ulmi (Wikipedia, CC BY-SA 4.0): what it looks like, where it lives, what it eats, sizes and fun facts, retold in simple words.
- Picture by Accipiter (R. Altenkamp, Berlin). CC BY-SA 3.0, Wikimedia Commons. The sticker of this bug is drawn from this picture.
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