Received: 31-10-2017 / Accepted: 25-12-2017
This study compared several morphological characteristics and reproductive biology of two fresh-water snail species, Pila polita(Pp) and Pila gracilis(Pg). The colors of the snail shells change over the stages in their life. With shell height <25 mm, Pp and Pg show green-yellow and green-dark color, respectively; with shell hight larger than 25 mm, Pp shell is green-dark and Pg is brown-yellow. Pila politaand Pila gracilisshow a close correlation between morphological characteristics such as shell height with shell width, shell height with total weight or shell height with meat weight. Results of broodstock conditioning and observations of some reproductive biology characteristics of two species showed that the weight and diameter of snail eggs, shell height and weight of newly hatched snails from Pila politawere higher than those from Pila gracilis(p<0.05).