Ultrafast launch of slingshot spiders using conical silk webs.

In the Theridiosomatidae spider family, at least three genera (Epeirotypus, Naatlo and Theridiosoma) use their three-dimensional cone-shaped webs as ultrafast slingshots that catapult both the spider and the web towards prey [1-3]. Also known as slingshot spiders, theridiosomatids build three-dimensional conical webs with a tension line directly attached to the center of the web. In 1932, Hingston [1] hypothesized that the slingshot spider releases the tension line using its front legs, while holding the web with its rear legs. Coddington [2] detailed how female spiders meticulously build their webs line-by-line. But lacking to date has been quantification of spider kinematics, such as displacement, velocity and acceleration. Here we report the first quantification of theridiosomatid motion, revealing that slingshot spiders generate the fastest arachnid full body motion through use of their webs for external latch-mediated spring actuation [4].