A Giant Among Spiders

Explanation: What a beautiful and startling arachnid this is! Behold the Giant Wood Spider ... also known as the Gold Orb Weaving Spider, the Tiger Spider, and other names.

This species is widely-distributed in the Indian subcontinent through southeast Asia and Australasia, and is secure, listed as "Least Concern" by IUCN. Nonetheless, it is a treat to find (again). Here, we encounter it in a small village in northeast India.

Their color markings apparently reflect ultraviolet light which could serve to attract bees and other visually-oriented prey species to their doom (Tso et al. 2004).

But there are examples where the wonderful silk of the Giant Wood Spider's web is actually stolen by other spiders, such as by the spider Argyrodes lanyuensis (Tso and Severinghaus 1998)! This is an example of one species stealing something from another species ... called kleptoparasitism ... which we have encountered in earlier EPOW episodes.

Like other spiders, such as the black window and red-back spiders, orb-weavers including this monster produce powerful neurotoxins that immobilize their prey.

Such neurotoxins are found to have potentially important value for pharmaceutical and pesticide industries (Jackson and Usherwood 1988).

This is another fine example of how nature can surprise us with an ecosystem service.

And, finally, break our your red-blue 3D glasses!
Enjoy this anaglyph,
and don't be scared!


Information:
     Jackson, H., and P.N.R. Usherwood. 1988. Spider toxins as tools for dissecting elements of excitatory amino acid transmission. Trends in Neurosciences 11(6):278-283.
     Tso, I.-M., C.-W. Lin, E.-C. Yang. 2004. Colourful orb-weaving spiders, Nephila pilipes, through a bee's eyes. Journal of Experimental Biology 207:2631-2637.
     Tso, I.-M. and L.L. Severinghaus. 1998. Silk stealing by Argyrodes lanyuensis (Araneae: Theridiidae): a unique form of kleptoparasitism. Animal Behavior 56(1):219-225.

EPOW - Ecology Picture of the Week