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A Guide to Common Singapore Spiders
by Joseph K H Koh
  Nepenthes Crab Spider
Misumenops nepenthicola (Pocock) 1898
close-up of bright red female
A female: inside a dissected pitcher of Nepenthes gracilis
It presumably attacks insects attracted by the sugary liquid secreted by the glands near the rim of the pitcher.

Eggs are laid on the inside wall of the pitcher
Classification: Family Thomisidae, Crab Spiders
Habitat: Lives inside the pitchers of the Common Pitcher Plant (Nepenthes gracilis), just below the rim.
Female: 6 mm.
Male: 6 mm.
Distribution: Singapore, Malaysia.
close-up of white crab spider
Some other Misumenops Spiders

These spiders live among foliage,
not inside the pitchers
of pitcher plants.
close-up of orangey spider
Crab spiders move sideways, like crabs. The body is not as hairy as in most spiders.

They are slow-moving spiders which do not actively hunt like Wolf Spiders. Instead, they remain stationary and await in ambush for some unsuspecting insects to land in front of them.

The first two pairs of legs in most Crab Spiders are longer and heavier than the third and fourth pairs, and are armed with spines for holding and grasping prey.
  From "A Guide to Common Singapore Spiders" by Joseph K. H. Koh
BP Guide to Nature Series published by the Singapore Science Centre and sponsored by British Petroleum
© 2000 Joseph K H Koh