TEMPERATURE ON BIOLOGICAL CHARACTERISTICS AND ADAPTIVE MECHANISMS OF THE APPLE SNAILS

Apple snails from the family Ampullariidae are large freshwater gastropods that are native to South, North and Central America. Some ampullariids, mainly from the genus Pomacea have been introduced out of their native areas, and subsequently caused serious damage to the freshwater habitats in such as Asia. The strong resistance and rapid adaptation to ecological stressors play key roles for the rapid spread and outbreak of the Pomacea species in their non-native ranges. With the efforts from researchers both in China and abroad, the invasive mechanisms on the resistance to various ecological factors of apple snails have been extensively investigated. Among which, the mechanisms on tolerance to cold and hot temperatures have brought the most research interests. Environmental temperature is crucial for the survival, growth, development, and reproduction of apple snails that serves as one of the key factors affecting their geographic distribution. We reviewed the ranges of survival temperature of both Pomacea canaliculata (Lamarck, 1822) and Pomacea maculata Perry, 1810, because both the species were the most widely distributed and economically important ones. Based on which, we summarized the physiological, biochemical, and molecular mechanisms in adaptive to high and low temperatures of P. canaliculata and P. maculata. The physiological and biochemical mechanisms on adaption to temperature of apple snails have currently focused on changes of the chemical compounds and enzyme activities. While the molecular mechanisms have mainly focused on the expression differences of several heat shock proteins. The chromosome level genomes of P. canaliculata has been sequenced in 2018, which will promote the ecological adaptive mechanisms of apple snails with the application of advanced genetic manipulation techniques.