It has all the ingredients of a Christmas miracle: not only a virginal mother but an expected late December due date. This time, however, the mother in question is Flora, a Komodo dragon.

Flora has astonished keepers at her home, Chester Zoo, by laying a clutch of seemingly viable eggs, despite having no mate.

"Essentially, what we have here is an imminent virgin birth and, because the eggs were laid back in May, it is not beyond the realms of possibility that the incubating eggs could hatch around Christmas time," said Kevin Buley, the zoo's curator of lower vertebrates and invertebrates.

"We will be on the look out for shepherds, wise men and an unusually bright star in the sky over Chester Zoo."

When Flora laid the 11 eggs, keepers discovered they contained embryos. Tests carried out by University of Liverpool scientists showed that Flora was both the mother and the father, a system of reproduction known as parthenogenesis.

Parthenogenesis - a term combining the Greek words for virgin and birth - occurs in some inspects, such as bees, as well as a limited number of vertebrates. A few other lizard species can reproduce without a male, but this is one of the very first times it has ever been reported in Komodo dragons.

In April, four Komodo dragons were born to a female, Sungai, who had not had a mate for two years. Sungai later went on to have young via traditional reproduction with a male.

The products of parthenogenesis are not clones, although they have exactly the same genetic make-up as the mother. All Flora's young could be different.

The news, details of which will be published next week in the journal Nature, had "very important implications for understanding how reptiles are potentially able to colonise new areas", Mr Buley said. "Theoretically, a female Komodo dragon in the wild could swim to a new island and then establish an entirely new population of dragons.

"The genetics of parthenogenesis in lizards means that all her hatchlings would have to be male.

"These would grow up to mate with their own mother and therefore, within one generation, there would potentially be a population able to reproduce normally on the new island."