Simon Williams has been trying for two years to persuade the snakes from Tanzania to mate, but the living conditions in the wild need to be replicated in captivity for it to happen. He says he knows of people in France and Germany who have successfully hatched live eggs, but he could be the first in the UK.

The hatched egg was one of two surprises last week. His wife gave birth to their baby boy last Monday and when he came back home from the hospital he found one of his two Thrasops eggs hatched. He said: "I have been attempting to breed them for two years. There are very few captive and we don't know the exact conditions of they come from, although it's in Tanzania in Africa.

"You just try a mixture of conditions - humidity and dampness - and then you've got the problem of the eggs and how long you incubate them. Similar snakes are 50 days, but these ones took 87 days. You just keep trying. I had two clutches - one last year - but the eggs died on me. This year two out of nine have survived and one has hatched up until now.

"It was probably more accidental last year. You have to give them time to recover apart, about four or five months and them start establishing them. They have a mating ritual where he will follow her around and will rub up against her. We have got several different species of snake as well as gerbils, rats, spiders and tarantulas."