SNAIL HOSTS OF PARAGONIMUS IN ASIA AND AMERICA

We have undertaken a comprehensive review of snail hosts of Paragonimus world-wide exclusive of Africa based on modern malacological data,where available,and with consideration of the phylogeny of the snail groups involved.This is the first comprehensive review since those made by Chen(1979)and Chen et al.(1983),and there have been considerable taxonomic changes over the past decade. A number of names and concepts found in the medical malacological and parasitological literature up to the present time require revision or correction.There ae vast radiations of snails of the superfamilies Cerithiacea and Rissoacea involved in the transmission of Paragonimus in CHina.We list 54 species world-wide of which 35(65%)occur in China.Revisions and corrections pertaining to China include:(i)the family Hydrobiidae does not occur in China or S.E.Asia and thd Pomatiopsidae should be used,(ii)The genus Bythinella is entirely European(Hydrobiidae:Amnicolinae).The so-called Bythinella of China belongs to the genus Erhaia(Pomatiopsidae).(iii)The generic name Pseudobythinella described from China is preoccupied,a junior synonym of Pseudobythinella Melville 1956,a fossil from england,ll chinese Pseudobythinella are now classified as Erhaia.(iv)Akiyoshia has been used as a generic name for some snails in Hunan transmitting Paragonimus,Akiyoshia is from Japan and biological/ecological data indicate tat the Chinese taxon is not Akiyoshia.(v)The genus Tricula in recent Chinese literature is comprised of four genera determined by detailed comparative anatomical data:Tricula,Neotricula,Gammatricula,and Jinhongia Shells cannot be used to discriminate among them.(vi)tricula cristella has been consistently misidentified in collections in China and literature.However,genuine T.cristella does transmit Paragonimus skrjabini.(vii)Tricula minutoides in the Chinese literature has been misidentified,and specimens,are T.cristella.(viii)The genus Melania and the family Melaniidae are used in the Chinese literature.The so-called melaniid snails belong