<p><strong>A river-spanning spider web dwarfs a park ranger in <a id="yvek" title="Madagascar" href="http://travel.nationalgeographic.com/travel/countries/madagascar-guide/">Madagascar</a> in 2008. Made of the world's strongest known biological material, the web is the product of a new species, the Darwin's bark spider, which makes the world's largest webs of any single spider, new studies say.</strong></p><p>Zoologist Ingi Agnarsson and colleagues have found Darwin's bark spider webs as wide as 82 feet (25 meters)—about as long as two city buses.</p><p>In Andasibe-Mantadia National Park (pictured), "the park rangers knew about them, and I think they've shown them to tourists for a while," said Agnarsson, of the <a id="hens" title="University of Puerto Rico" href="http://biology.uprrp.edu/department_info/index.html">University of Puerto Rico</a>.</p><p>But the Darwin's bark spider and its record-breaking webs were unknown to science until they were documented by the team, whose findings appear this week in the <em><a id="vxyt" title="Journal of Arachnology" href="http://www.americanarachnology.org/JOA_online.html">Journal of Arachnology</a> </em>and <em><a id="kibi" title="PLoS ONE" href="http://www.plosone.org/home.action">PLoS ONE</a>.</em></p><p>(Related: <a id="nft1" title="&quot;Largest Web-Spinning Spider Found.&quot;" href="http://news.nationalgeographic.com/news/2009/10/091021-largest-web-spinning-spider.html">"Largest Web-Spinning Spider Found."</a>)</p><p><em>—Ker Than</em></p>