One of the world's largest frogs, Britain's only native crayfish and Amur leopards, are among the creatures staving off extinction with the help of UK zoos.
A list of species whose future is most reliant on conservation programmes by domestic zoos has been drawn up by the British and Irish Association of Zoos and Aquariums (Biaza) to highlight their work to save wildlife.
The top 10 list includes Polynesian tree snails, the Potosi pupfish from Mexico and the Scimitar-horned oryx from Tunisia, Morocco and Senegal, which are all extinct in the wild.
The critically-endangered mountain chicken frog, facing extinction in its Caribbean home from exploitation by humans, habitat loss and a deadly fungus, is being bred in captivity in the UK.
Just 45 Amur leopards remain in the wild, but there are 220 of the critically endangered cats in a global conservation breeding programmes in zoos around the world, with a reintroduction scheme currently in the planning stages.
Around 95% of Britain's white-clawed crayfish have vanished from the country as a result of the introduction of American signal crayfish and disease, prompting UK zoos to breed the species for release in safe areas in the wild.
The top 10 list also includes ploughshare tortoises and the blue-eyed black lemur, both from Madagascar.
Zoos are also helping the blue-crowned laughingthrush, whose population numbers less than 250 mature birds in the wild in China, and even a tree, the Verdcourt's polyalthia, which is found in just three places in the Kilombero valley, Tanzania.
Dr Andrew Marshall, from Biaza, said: "Without the valuable conservation and breeding work of many of our member zoos and aquariums, many 'at risk' species such as these may be lost to extinction forever."
The top 10 were chosen from hundreds of zoo-backed conservation programmes, focusing on species at high risk of extinction.