Orb-weaver spider here basically unchanged since Jurassic

This critter, now called a living fossil, made its home in Ciudad Colón when this photo was taken several years ago. It's hard to miss these spiders with the body length of two inches or more. Photo: A.M. Costa Rica

University of Kansas scientists are thrilled because they found a Jurassic period spider fossil in China. They could have found the same type of critter very much alive in the Central Valley or hundreds of other Costa Rican locations.

The spider is the golden orb-weaver, which seems to have changed little in the last 175 million years. The fossil and its modern descendants have a leg span of more than five inches. The female spiders weave webs as much as 1.5 meters in diameter. That is nearly five feet.

The University of Kansas said that the fossil was found near Daohugou, China in a joint effort with the Capital Normal University in Beijing. Paul A. Selden, a professor at Kansas and Chinese colleagues authored a report on the find in Biological Letters, an online research journal. He said that the many millions of years was an extremely long range for any animal genus, said the university which called today’s spiders living fossils. They are frequent in tropical areas nearly all over the world. The genus is Nephila.

Today’s spiders generally feed on insects but can handle an infrequent small bat or bird. The spiders are striking because of the golden web and because of the size of the creature.

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