Cercarial Fauna of India: Occasional Paper No. 414

Contents: 1. Introduction. 2. History and classification. 3. Methodology. 4. Acknowledgements. 5. References.

Studies on larval trematodes began in 18th century. Muller (1773) for the first time coined the term “Cercaria” to describe microscopic animals with tails. It was used as generic name because the larval stages were considered adult trematodes as no one could suspect the need for a host change to complete life cycle. In early 19th century cercariae were also considered to be independent organisms of unknown taxonomic position. After study of Steenstrup (1842) the cercariae were regarded as larvae which attain sexual maturity after entering into gut of vertebrates. Diesing (1855) still considered them to be adults which later in 1858 he accepted as larval trematodes. With increasing knowledge, their importance in taxonomy was realised. Luhe (1909) made first serious effort to classify them. Our focus on Indian Fauna of Cercaria and Zoological Survey of India has been the lead as afar as basic research in malacology and helminthology in concerned. The two disciplines have grown up also most together. In fact, the thrust that was given to freshwater mollusc studies in the beginning of this century was largely due to the fact that these are intermediate hosts of helminth parasites, namely the flukes or the trematodes.