Sir James Goldsmith, its leader, announced that Dr Bellamy is the party's choice to take on the Prime Minister at Huntingdon in the General Election.
It makes no difference that the environmental campaigner has never voted and has no wish for power. "He is one of our greatest botanists, writers, broadcasters and campaigners for the environment, a lover of the English countryside and a great lecturer," said Sir James, introducing him to 400 of his fellow prospective parliamentary candidates at a rally in Manchester.
"He is a founder of the Conservation Foundation and his infectious love of nature has inspired millions and made him into the figure that he is. He is a great asset to the party, who is enormously respected."
Dr Bellamy said: "I have watched Mr Major on Prime Minister's question time and I would hate to be Prime Minister. What an awful job for bad pay - to stand there and get that c--p thrown at you twice a week!"
As to Huntingdon, he said he was familiar with the ecology of the constituency and had visited its dogs' home, but he did not think he would spend much time there during the campaign as he doubted if Mr Major would know who he was.
"If I get less than 2,000 votes I would be slightly miffed, but I am standing against the Prime Minister," he said.
Dr Bellamy revealed he had been talked into standing by Sir James after saying that he would vote for the first time for the party because he felt so strongly about Europe.
"The two potential leaders of the next government have been swinging backward and forward about whether we should be in or out - especially over the single currency. I know as an ecologist that a single unit cannot work, we need biodiversity.
"I don't want to see this country stick its head into something we won't be able to get out of.Britain is faced with a catastrophic future if it goes willy-nilly into a federal state run by unelected bureaucrats - faced with saying 'Yes Minister' in 24 languages."
Dr Bellamy said he thought the British people were going to demand a referendum. "We are not trying to get into power to run the country. We are trying to give the country the chance to run itself within Europe. We have got to keep Britain as a nation which is free to act and stand against the tyrannies of the rest of the world."