Spiny Orb-weaver
Gasteracantha falcicornis
This spider was observed at City Park, Nairobi, Kenya, October 2010. Roy Erling Wrånes kindly supplied the species name.
An orb-weaver spider sitting patiently in the center of her web is a waiting target for a hungry, skilled bird to pluck out and eat. But Gasteracantha spiders have evolved sharp abdominal spines that discourage such predation. Just in case the sharp-eyed predator forgets how unleasant this meal would be, the spider also shows bright warning coloration.