HONG KONG (KTVX/NEXSTAR) — A university scholar has discovered novel reproductive behavior in a frog species native to Hong Kong.

According to the Science Unit of Lingnan University (LU) in Hong Kong, a student has discovered that the female among Lau’s Leaf Litter Toads positions herself on top of the male, which is a reversal of the more usual mating arrangement.

“The discovery of this new mating behaviour demonstrates the variety of natural wonders even in a small city like Hong Kong,” Sung Yik-hei, the assistant professor of the science unit, said in a statement.

Officials deemed the mating behavior of the Lau’s Leaf Litter Toads — which is native to the city of Hong Kong — as “unconventional.”

According to LU, Field surveys were conducted in the city between 2010 and 2017 to observe interactions between the male and female frogs.

According to Sung, frogs and toads use external fertilization. The female releases her eggs outside her body, and the male releases his sperm on the eggs at the same time.

Usually during mating in frogs and toads, Sung said, the male mounts the female or places himself horizontally to align his reproductive organ with those of the female. However, in Lau’s Leaf Litter Toads, the male gives the female a “piggyback ride to a hidden location where they complete reproduction.” Sung said the process is called “sex-reversed inguinal amplexus.”

“This behavior has not been observed in other species of frogs and toads, but the frogs conceal themselves soon after pairing so that it is hard to determine if this is simply a ride on the male’s back or how the eggs are fertilized,” Sung said. “In fact, despite the endeavors of local herpetologists, Lau’s Leaf Litter Toad eggs have never been documented before.”

Sung said the discovery, which was published in the latest issue of the international academic journal “Ecosphere,” is a boon to wildlife conservation efforts.

“Through keen observation and persistent hard work, we can begin to understand more about nature,” he said. “This gives us the ability to conserve the amazing Hong Kong wildlife.”