A flightless cicada that evolved before the dinosaurs and was thought to have been extinct for 80 years has been found alive on an island off the Australian coast. Jubilant scientists yesterday compared the discovery of the giant flightless insect as "the most significant event since the discovery of the Wollemi Pine". Dryococelus australis, which grows 15 centimetres long and has a body 1.5 centimetres thick, was once thought to have inhabited only Lord Howe Island. Lord Howe's cicada survived the dinosaurs, only to be wiped out in 1920 by rats that arrived aboard the supply ship Mokambo in 1918. Last week scientists from the National Parks and Wildlife Service and the Australian Museum went to Balls Pyramid, a volcanic rock jutting out of the sea 23 kilometres from Lord Howe Island, to investigate reported sightings of the dead cicada or phasamils. They found droppings but were unsure if they were from the nocturnal animal. After dark, Mr Nicholas Carlile, a wildlife service scientist, and Mr Dean Hiscox, a Lord Howe Island Board ranger, climbed 100 metres up a cliff. There they found three of the female insects feeding on a tea tree. "I was lost for words, except for the odd expletive," Mr Carlile said yesterday. "We couldn't jump for joy for fear of falling off the 60 degree slope." Another member of the group, Dr David Priddel, a senior wildlife service research scientist, described the find as far more exciting than the discovery of the Wollemi pine. "They move," he said, adding: "We are jumping out of our skins. There is nothing else like it. They become the rarest insects in the world." Dr Priddel said the insect, which evolved so large because it originally had no enemies, looked like "a walking sausage". He said that during the 1960s climbers on Balls Pyramid reported finding strange dead creatures resembling the long-lost cicada. Despite the observations, scientists were sceptical that the leaf-eating insect, assumed to live in only forest trees, could survive on such a desolate island. Dr Priddel, who suspects there may be as few as 10 survivors, said the next step would be to establish a breeding colony on Lord Howe Island.