ileum. Isolated BRPs from A. torrentis have been shown to have a contractive effect on the smooth muscle of rat ileum in the laboratory setting. BRPs are thought to play a role in defense against predators, as the contraction in the ileum may stimulate the gastrointestinal system of a predator to cause vomiting and other unpleasant reactions. This deters the predator from consuming members of A. torrentis again. Threats Parasites Individuals of these species suffer from parasitism from blood-sucking parasites like frog-biting midges. These midges are attracted to the acoustic signal given by male members of A. torrentis, which results in limb movements to defend against these parasites. The limb movements include toe trembling, hind foot lifting, arm waving, limb shaking, wiping, leg stretching, and foot flagging. These movements may also be incorporated into a sexual display, as males that display these parasite defensive limb movements are perceived as more attractive by female members of the species. This species also suffers from parasitism from nematodes. Nematodes from the family Acuariidae have been found as stomach cysts in museum samples from this species. Conservation A. torrentis is listed as vulnerable by the IUCN, as last assessed in 2019. It was given this classification because its area range is only 15,838 km^2 in Hainan. Its habitat in Hainan is declining in terms of the extent and quality. Identified threats to the species include annual and perennial non-wood crops, wood and pulp plantations, logging and wood harvesting, dams and water management, and agricultural and forestry effluents. Previously, it had been a concern that the construction of hydroelectric plants in Hainan would pose a threat to A. torrentis. However, this concern has been alleviated by the fact that the construction of these plants has occurred and no new plants are planned, and no major damage to the species population has been observed. Habitat Loss In particular, an increase in the number of rubber plantations, banana plantations, and areca crops are decreasing the size of the forest habitat for A. torrentis. This also polluting the habitat with herbicides and pesticides. Such habitat loss is particularly concerning because A. torrentis is only found on the island of Hainan. Conservation Efforts To combat the threat of habitat loss, A. torrentis is present in several protected areas in Hainan, including nature reserves and forest parks. In addition, it is also on the "List of Beneficial or of Important