In 2023 and 2024, Chinese scientists collected specimens of a previously unknown snake in the Quan Am Mountain nature reserve in Yunnan, China.
Researchers identified it as belonging to the Ovophis genus of pit vipers, but genetic and morphological analyses revealed clear differences from known mountain pit viper species.
In 2025, the species was formally described as new to science under the name Ovophis zhaoermii, commonly known as the Quan Am Mountain pit viper. The scientific name honours Chinese herpetologist Ermi Zhao.
Like other pit vipers, the species has a distinct triangular head set apart from the neck, a relatively slender body and a short, tapering tail. It measures between 0.5 and 0.67 metres in length. Its head lacks markings, while the back is dark brown or reddish brown with large black rectangular blotches, and the tail features a continuous white-spotted band.
The snake was observed at night on the ground near streams, suggesting it is nocturnal and likely preys on amphibians such as frogs.
Initially, scientists believed the Quan Am Mountain pit viper to be endemic to a single population within the Quan Am Mountain nature reserve in southern Yunnan.
However, new research shows the species is also present in Vietnam.
Two adult female specimens, whereas all previously collected individuals in China were male, were found on Po Ma Lung Mountain in Lai Chau Province. Morphological and genetic analyses confirmed them as Ovophis zhaoermii.
Field observations in Vietnam indicate the species inhabits open forests with evergreen broadleaf canopies, low shrub layers and ground vegetation. It typically rests on rocks near streams or on rocky outcrops along stream banks to avoid flowing water, and is active at night.
Notably, Chinese studies recorded the species at elevations below 2,400 metres, while findings in Vietnam place it at higher altitudes ranging from 2,277 to 2,559 metres above sea level.
Like other members of the pit viper family and the Ovophis genus, the species possesses venom that can be dangerous to humans. However, its preference for remote high-altitude habitats means encounters with people are likely to be rare.
As a recently described species with limited specimens collected, its population size remains unknown. Scientists have proposed listing the guan am mountain pit viper in the red data book as a priority species for conservation to reduce the risk of extinction.
With the discovery in Lai Chau, Vietnam now records five species of mountain pit vipers, including Ovophis monticola, Ovophis anitae, Ovophis tonkinensis and Ovophis cf. meridionalis.
