Compared with mammals and birds, amphibians and reptiles require more targeted conservation efforts, Wang Yingyong, a leading herpetologist from the School of Life Sciences at Sun Yat-sen University in Guangzhou, Guangdong province, told China Daily.

"These species are often distributed in smaller habitats, overlooked by the general public and are particularly sensible to environment changes," said Wang, who is also deputy director of the school's herbarium. "They are usually too small to be considered as flagship species and only a few of them have been put under the State protection. As a result, some species may have already faced extinction before we knew."

From 2010 to 2022, Wang and his team launched a project to systematically collect topotype specimens — specimens collected in the same locality where type specimens were found — of more than 300 amphibian species distributed in the country and their DNA data for their classification research.

They conducted multiple visits to over 210 sites across the country where frog type specimens had been obtained. Although they managed to collect specimens of the majority of their targeted species, there were instances of failure, Wang said.

For example, a species of Ophryophryne distributed in Mengla county, Xishuangbanna prefecture in Yunnan province, has evaded their search efforts.

"The type specimen of the frog was collected from an area near a river in Mengla," Wang said. "We visited that site five or six times and made thorough searches along the river, but failed to find the frog."

Without the frog's specimen and DNA data, he said, he and his colleagues cannot identify some Ophryophryne species they discovered in Guangdong.

"We are uncertain whether the species may have already become extinct," he said. "Nevertheless, we are committed to continuing our search."

During the years, the researcher said, he has even witnessed the rapid disappearance of some species.

In 2008, he and his students discovered a new species of horned toad at Heishiding nature reserve in Fengkai county, Guangdong. In 2014, the species, Boulenophrys obesa, was published and named after the nature reserve.

Sun Yat-sen University's School of Life Sciences has established a field research base at the reserve and mapped out a permanent plot to monitor indigenous forest.

At the permanent plot, they found the horned toad and collected the type specimen. From that point onward, up until 2014, they typically gathered one or two specimens during their fieldwork at Heishiding. However, after 2014, they no longer encountered any of the species again at the permanent plot.

"Over the years, numerous students from our school would visit the plot, gathering samples of every plant thriving in that area," Wang said. "We extensively explored the area, treading upon the forest floor. Such human interventions could potentially have adverse effects on the local environment. Sensing these changes, the frogs gradually vanished from the vicinity."

He said that the horned toads could possibly still inhabit some other area within the reserve. "However, my certainty remains in question until we manage to spot them once more in their natural habitat," he added.

chenliang@chinadaily.com.cn