Database of Trematoda

from East and Central Europe

Parasites of fish

Parasites of bivalvia

Parasites of Lithoglyphus

Reports

Publications

 Trematoda are parasitic flatworms known as flukes. Flukes are characterized by high species diversity (about 25000) and the complex life cycles. Adults are obligate parasites in a variety of vertebrate animals. All flukes use molluscs as first intermediate hosts in which asexual reproduction occurs. Freshwater bivalves of Palaearctic are mainly infected with flukes of families Gorgoderidae and Allocreadiidae, which reach sexual maturity in fish. Lymnaeoidea and prosobranch snails are intermediate hosts for variuos species of parasitic flatworms. Examination of mollusks for larval flukes is the keystone for the determination of the autochthonous fauna in the region under study and for the determination of the probability for vertebrates to be infected with pathogens. Unfortunately, life cycles and larval forms of most species still are unknown. On the other hand, many larval forms are described, the adults and taxonomic position of which is unknown. Morphological features are insufficient to link larval and adult flukes. Experimental laboratory studies are complex and not always give reliable results. The reevaluation of the systematic characteristics currently used and the search for new characteristics has been greatly facilitated by use of molecular markers. We studding larval flukes infecting molluscs in Lithuania and adjacent regions. Karyotypes and rDNA sequences of species will be determined. Comparative analysis will be made using original and GenBank data. We will also analyze fixed material sent by our colleagues, and adults obtained by dissection of vertebrate animals, the suppositional final hosts of studied larval flukes. The molecular phylogenetic analysis will help to link the larval forms found in the bivalves and adults, to clarify taxonomic position of unidentified larvae and to evaluate existing biodiversity. The accumulated data are placing on the Internet in this database  for species identification, biodiversity analysis and assessment of changes in ecosystems.