Oncomelania hupensis (Gastropoda: Rissooidea) in eastern China: molecular phylogeny, population structure, and ecology

• Published in: Acta tropica 2000-11, Vol.77 (2), p.215-227
• Main Authors: Wilke, Thomas, Davis, George M, Cui-E, Chen, Xiao-Nung, Zhou, Xiao Peng, Zeng, Yi, Zhang, Spolsky, Christina M
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; China; Cytochrome oxidase I; DNA sequencing; DNA, Mitochondrial - analysis; DNA, Mitochondrial - genetics; Ecosystem; Electron Transport Complex IV - genetics; Evolution, Molecular; Fundamental and applied biological sciences. Psychology; Genetic Variation; Haplotypes; Medically important nuisances and vectors, pests of stored products and materials: population survey and control; Molecular Sequence Data; Oncomelania hupensis; Phylogeny; Polymerase Chain Reaction; Population genetics; Sequence Analysis, DNA; Snails - classification; Snails - genetics; Tropical medicine; Vectors. Intermediate hosts
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/S0001-706X(00)00143-1

The rissooidean snail genus Oncomelania is of medical interest as various taxa are hosts for the human blood fluke Schistosoma and the lung fluke Paragonimus; because of close co-evolved host-parasite-relationships, snail diversity may reflect parasite diversity. There is a considerable amount of confusion regarding the identity of smooth- and ribbed-shelled populations of Oncomelania hupensis in eastern China. We therefore studied the genetic variation, population structure, phylogenetic relationships and ecology of five smooth- and five ribbed-shelled populations in Hubei, Hunan, Anhui, Zhejiang, and Jiangsu provinces. Based on sequencing data of a fragment of the mitochondrial gene for cytochrome oxidase I from 80 individuals, we found little genetic variability within the ingroup-individuals studied here (average π=0.01922). Moreover, within the ingroup, smooth-shelled individuals cluster together with ribbed-shelled individuals. We therefore consider all smooth- and ribbed-shelled populations of Oncomelania throughout the lower Yangtze River basin to belong to the subspecies O. hupensis hupensis. Our data indicate that ribbing in O. h. hupensis is associated with the annual floods of the Yangtze River. The greatest haplotype ( d H) and nucleotide diversities ( π) are found in aggregates of ribbed-shelled snails along areas of the Yangtze River drainage subject to flooding. In areas not affected by flooding, the shells are smooth and genetic diversity decreases significantly.