Comparison on main morphologic characters for different varieties of Pomacea canaliculata in China

Based on the characteristics of Pomacea canaliculata's external shell and its soft part,they were divided into 3 types: black P.canaliculata,yellow P.canaliculata,and grey P.canaliculata.HE staining of their breathing tubes and feet proved that the different colors of the soft parts mainly resulted from the existence of melanin granules and the number of deposition.During the observation of the radula of P.canaliculata,the ratios of the first and second cusp to the centre radula of grey P.canaliculata largely exceeded that of the black and grey P.canaliculata.The differences of the three types were difficult to judge under scanning electron microscope.It's suggested that the analysis of the above differences of P.canaliculata would provide evidence in the researches about the treatment of angiostrongyliasis and the control of spread of P.canaliculata.