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Crab Spider

Scientific Name:

Thomisidae (taxonomic family)




All types except dry deserts and very cold mountains




Species range from Least Concern to Critically Endangered (IUCN Red List)

This species is


to the Truckee Meadows.


Any spider within the family Thomisidae is considered a crab spider. Crab spiders can usually be identified by their flat, short, and wide bodies. These spiders get their name from their tendency to walk sideways or backwards with their hind legs held open to grab prey. They are tiny spiders, with females much larger than males. Females grow to between 0.16 and 0.3 inches long, and are usually green, white, or yellow with two red dots. Males are usually darker with brown stripes and a greenish-white underside.

Fast Facts:

  • There are over 2,000 species of crab spiders around the world, and over 200 in North America alone.

  • While crab spiders can produce silk, they do not use it to construct webs. Instead, they hunt and catch their prey by camouflaging with their surroundings before ambushing.

  • Despite not being used in web building, crab spiders' silk is still very important. These spiders use their silk both for wrapping their eggs and to form balloons to lift them away in the air.

  • Female crab spiders protect their eggs and wait for them to hatch, a process which can take around three weeks. Females do not eat during this time, subsequently dying from exhaustion and lack of food shortly after the eggs hatch.



Haley McGuire (research & content)

Alex Shahbazi (edits & page design)

Last Updated:

March 27, 2024 at 1:48:22 AM

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