Cribellate Orb Weaver (Uloborus spp.)
Detailing the physical features, habits, territorial reach and other identifying qualities of the Cribellate Orb Weaver.
Updated: 2/26/2018; Authored By Staff Writer; Content ©www.InsectIdentification.org
The tropical Cribellate Orb Weaver spins a very fine silk web that uses design, not substance, to tangle its prey.
The legs of the Cribellate Orb Weaver have flared, feathery tufts of hair at the 'ankles'. The front pairs of legs are extremely long. Oftentimes these front legs are stretched out in front of the spider, grouped next to each other. This position elongates the spider while it sits on its web. Two bumps at the top of the abdomen help disguise the brown and white speckled abdomen.
Webs are built flat and parallel to the ground, at or around knee-height. The spider sits on it, or near it, in its tucked position. Sometimes it lies in wait on the underside of the web, giving it the appearance of a dead flower or piece of leaf. The Cribellate Orb Weaver creates a web that lacks sticky silk. The web itself has tiny gaps between the strands that easily catch the legs of insects landing on it. Small prey get easily tangled, rendering sticky silk unnecessary. The cribellum on the legs allow the spider to 'comb' its web, keeping the fine strands separated until prey enters.
This tiny spider is found in humid, tropical climates and is one of the only spiders that lacks venom. Instead of chemically immobilizing their prey, Cribellate Orb Weavers kill their victims by winding them tightly in silk, squeezing them to death.