Giant salamanders, one of the world’s largest frogs and turtles with heads too big for their shells are among the creatures with a new home at London Zoo.

The new “secret life of reptiles and amphibians” exhibit opens to the public on March 29, housing more than 30 species, including critically endangered wildlife and some which are highly unusual and distinct from any other animals.

It replaces the old reptile house at London Zoo, and hosts some of the world’s stranger and lesser known creatures, supporting their conservation, captive breeding programmes and research that could help wildlife in the wild, the Zoological Society of London (ZSL) said.

For the first time, visitors will be able to see the zoo’s group of mountain chicken frogs, which were airlifted to safety from their Caribbean home in 2009 in a last-ditch bid to save the species from extinction due to a killer fungus.

They are kept in a biosecure unit to protect them from disease, with sterilised soil and plants dipped in dilute bleach solution, before being placed in the enclosure and staff changing their clothes before working with them.

Also among the residents of the exhibit are two Chinese giant salamanders, the world’s largest amphibians, which were rescued from being smuggled in a cereal box in 2016, before coming to live in the zoo.

It is hoped the critically endangered animals will breed – if, as the keepers think likely, they are a male and female.

Some 16 of the creatures in the exhibit are “Edge” species – which means they have few evolutionary relatives and are often extremely unusual in their genetic make-up and the way they look, live and behave.

They include the crocodile lizard, which has no more that 1,000 individuals in the wild in southern China and northern Vietnam, and the big-headed turtle, which has a large head it cannot retract into its shell.

Four adult big-headed turtles came to the zoo in 2018, having been confiscated after being smuggled in Canada, and seven youngsters were born in 2021, making London Zoo the first European zoo to breed them.

Amphibian and reptile species are threatened by habitat loss and being caught for meat and the pet trade, while amphibians in particular are at risk from disease such as chytrid fungus which all but wiped out mountain chicken frogs.

The team at ZSL say having animals in their care means they are able to research and learn about their lives and behaviour in ways that can help their survival in the wild.

For example, they are carrying out analysis of their Ethiopian mountain adders to see if the patterns on the snakes are stable, and if so could be used as identifiers of individual snakes which would support monitoring and conservation in the wild.

The secret life of reptiles and amphibians building has been designed to meet the needs of each of its 33 species, with different climate controlled zones, and staff checking temperatures, water quality and humidity on a daily basis.

It also gives visitors a glimpse into some of the behind-the-scenes breeding and animal care areas.

Dr Ben Tapley, curator of the exhibit, said they had developed a facility that could provide for threatened species and improve breeding success.

He added: “It is showcasing things that are completely different from ourselves and making people see species in a new light.

“All of these animals are quirky, they’re weird-looking, they’re completely different from anything else, and each one of them has a unique story.”

He said the survival of some species such as the mountain chicken frog is dependent on the captive populations.

Very little is known about other species, and by having them in the zoo’s care, staff could address knowledge gaps that would help with their conservation.

Dr Tapley said it was easy to get funding for large charismatic animals, but they were not always the most threatened.

In the creatures in the new exhibit, the zoo had “excellent ambassadors” for raising awareness and support for highly threatened reptiles and amphibians, he said.

“I hope by telling the stories of some of these lesser known animals, we can get greater support for their conservation,” he said.