Friday, April 2, 2021

[Herpetology • 2021] Novel Reproductive Behavior in An Asian Frog: Sex‐reversed Inguinal Amplexus [Leptobrachella laui; Megophryidae]

Leptobrachella laui (Sung, Yang, and Wang, 2014)

in Sung, Lee, Ng, et al., 2021. 

Amphibians exhibit diverse reproductive behaviors, including nine documented types of amplexus, the behavior in which male and female frogs position themselves for courtship, oviposition, and fertilization. All known forms of amplexus involve the male on top of or in line horizontally (cloacal apposition) with the female. Here, we report a novel form of amplexus observed in Lau’s leaf litter toad (Leptobrachella laui; Megophryidae) in Hong Kong, China. Termed “sex‐reversed inguinal amplexus,” the female climbs on top of a male and the male transports the female to a concealed breeding site. We were unable to determine whether this was the amplectant position in which frogs engaged during oviposition or solely during courtship and prior to oviposition, but there are a number of possible evolutionary drivers that may have given rise to this behavior, including limiting suitable oviposition sites or strong competition for males among females. Further research will be necessary to understand the evolutionary origins of this novel reproductive behavior.

Keywords: amphibian, amplexus, behavioral ecology, Leptobrachella laui, Megophryidae, oviposition

A pair of Lau’s leaf litter toads (Leptobrachella laui) in sex‐reversed inguinal amplexus, in which a female is on top of a male, in Hong Kong, China in March 2017.

Yik‐Hei Sung, Wing‐Ho Lee, Ho‐Nam Ng, Martha L. Crump and Nancy E. Karraker. 2021. Novel Reproductive Behavior in An Asian Frog: Sex‐reversed Inguinal Amplexus. Ecosphere Naturalist. DOI: 10.1002/ecs2.3407
Lingnan University scholar discovers novel reproductive behaviour in native frog species