To the ecology of trematodes Opisthioglyphe ranae (Telorchidae)

The trematode Opisthioglyphe ranae is a usual intestine parasite contaminating 35 species of reptiles in Eurasia. However, the differences between marites having various development types have not been established. We studied the contamination of the moor frog (Rana arvalis) with the trematode Opisthioglyphe ranae in the dry steppe, the floodplain of the Irtysh River and anthropogenic biotopes of Kazakhstan. It was established that the O. ranae realizes both forms of its life cycle in all the studied habitats. The complex of O. ranae in the populations of the final host is structured and annually composed of two generations of mature individuals: the first has a three-host (trixenous) history of the development, but the second is formed according to the two-host (dixenous) variant of its life history. The first generation of trematodes is distributed in all R. arvalis, except for tadpoles and young-of-the-years. The formation of this generation of trematodes is connected with the feeding sites of a definitive host. The second generation is annually formed in May-June in spawning reservoirs, where O. ranae cercariae infect tadpoles and frogs' males. Individuals with a dixenous history of formation account for 30-35% of all sexually mature O. ranae.