Sunday, 18 July 2010

Gotcha

This little Jumping Spider, Salticidae, has occupied the same couple of centimetres on one of my orchids. It has been in the same place every day for over a month. At night it moves to an adjacent stem where it hides under a dead leaf.

Jumping spiders have very good eyesight. The eyes can create a focussed image on the retina which has up to four layers of receptor cells providing them with tetrachromatic colour vision. This extends into the Ultraviolet range.

Jumping spiders are active hunters and do not use the web for this purpose. They are peculiar in that some have been observed feeding on nectar and pollen, a dietary mode not usually associated with spiders.

There are not many insects in my shade house but the spider lucked out when it came upon this fly and nabbed it.
Note the strand of silk to the upper left. This is so the spider can regain its original site should it fall or leap for an insect. The hundreds of micro hairs at the tip of each foot allow the spider to cling to any surface, vertical or otherwise.

This is lurking Crab Spider has hidden in this ginger flower for days. Note the little spider above.
It is the White-faced Crab Spider, Thomisus spectabilis, aptly named. See the white horizontal band through some of its eyes. Note the strand of silk. This serves the identical purpose for the crab spider noted above for the jumping spider. Crab spiders do not produce typical webs but they do produce silk to help them regain their posts.
The spider is feeding on another spider. It could be the one noted in the photo above but it seems to be a small Huntsman, another spider that marauds at night and has no orb-like web.

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