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A Guide to Common Singapore Spiders
by Joseph K H Koh
  Common Two-Tailed Spider
Hersilia sp.
close-up of camouflaged female
In resting position, the flattened lichen-coloured body is pressed against the tree trunk, thus blending perfectly with the surrounding bark, and casting little or no shadow to betray its presence.
Classification: Family Hersiliidae, Two-Tailed Spiders.
Habitat: Tree trunks in gardens and jungle fringes.
Female: 8.5-10 mm.
Male: 6-8 mm.
Living almost exclusively on tree trunks or stone walls, they immobilise their prey by spreading silk while jumping over and running around it.
When alarmed, the spider erects its two long spinnerets and darts to the opposite side of the tree with a movement so swift that all one can see is an apparent blurring of a part of the bark.

Two of the spinneretes are disproportionately long and pointed, hence the name "Two-Tailed Spiders". The head region is elevated above the rest of the cephalothorax. The body is compressed and legs are exceedingly long (except the third pair).
close-up of male face showing palps
Face of a male
Two-Tailed Spider
  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