Spiny orb weaver

Spiny orb-weavers is a common name for Gasteracantha, a genus of spiders. They are also commonly called spiny-backed orb-weavers, due to the prominent spines on their abdomen (cf. genus Isoxya). These spiders can reach sizes of up to 30 mm in diameter (measured from spike to spike). Although their abdomen is shaped like a crab shell with spikes, it is not to be confused with a crab spider.

Often brightly colored, spiny orb-weavers have a broad, hard abdomen that can be white, orange, or yellow with red markings. The female shell is ringed by six red or orange spines, whereas the smaller male lacks the spiny projections and instead has four to five stubby dark projections.

Orb-weavers' bites are generally harmless to humans.