Non-toxic, there are 9 genera in Oncology. It is distributed all over the world except South America. There are more than 70 known species in China, among which Oncomelania species are only distributed in Heilongjiang and Jilin provinces in China. Ampulla and ampulla are distributed in Palaearctic and East Asia. The other six genera are oriental species, snails and snails are endemic to China, snails are only distributed in lakes in Yunnan Province, and snails are distributed in Hunan and surrounding provinces, mainly inhabiting rivers.

Some species of Oncomelanidae are 1 and the second intermediate hosts of Echinococcus. Some species multiply in large numbers, causing the cooling water pipes of Yanhe Lake factory to be blocked.