Eight-armed animal preceded dinosaurs

Scientists have discovered what they believe is an eight-armed creature, which colonized a large section of the world's oceans over 300 million years before the first dinosaurs emerged.  The findings represent the first comparable animal fossils from the Ediacaran Period, 635 to 541 million years ago, which appear in two drastically different preservation environments - black shale of South China and quartz rock of South Australia.  

http://www.abc.net.au/science/articles/2008/11/04/2409959.htm?site=science