MAIN GOALS AND TASKS

• "Developmental biology and evolution of living systems" includes the studies on phylogeny of parasites, origin of parasitism in nematodes and reconstruction of evolutionary development in certain groups of parasites.
• "Ecology of organisms and communities" – the studies on ecology of soil-dwelling entomopathogenic nematodes; and
• "Biological diversity" includes the studies on taxonomy, specific diversity and bionomics of several groups of parasites in Russia, neighbouring and tropical countries.

Most important achievements

The Laboratory of fauna and systematics of parasites (previously "the sector" under the same name of Helminthological Laboratory of the USSR Academy of Sciences), at the moment of its foundation in 40-50 of the last century by Academician K.I. Skrjabin, was the first separate unit of academic science in the country aimed exclusively at taxonomy and systematics of worm-like parasitic organisms (helminthes). In three decades there were numerous volumes of ‘Essentials’ on nematology, trematology and cestodology contributed by the leading researchers on this lab (K.M. Ryzhikov, the Corresponding Member of the USSR Academy of Sciences; Prof. V.E. Sudarikov; V.I. Freze, D.Sc.). The Essentials were translated into English and still serve as a valuable source of information for taxonomists in many countries. Currently, the laboratory carries out the studies on taxonomy and systematics of the wide range of parasites from poorly known nematodes parasitic in invertebrates to economically significant fish trematodes and nematodes of ungulates. Still, the search of characters resolving position of a higher taxa in different groups of parasitic organisms remains an important direction in the research work of the Laboratory. In collaboration with researchers from other RAS Institutes, it has been discovered that localization of entodermal primordium in early embryogenesis of Nematoda differs significantly among representatives of three basic evolutionary lines of nematodes. Thus, the entodermal primordium originating from the anterior blastomere on two-cell developmental stage is characteristic for Dorylaimia, - from posterior blastomere - for Chromadoria. In Enoplia entoderm can derive from any cell of two-blastomere stage.

The Museum for helminthological collections has been maintained for several decades already. It is internationally registered and provides material for researchers worldwide. The work with collections includes, apart from the usual routine of maintenance, its replenishment and systematization of unidentified materials. Recently, materials collected in previous expeditions to the Darvinskiy and Astrakhanskiy Natural Reserves, Ob and Yenisei rivers, Turkmenistan, Lithuania and Tuva was sorted out, identified, catalogued, and included into the Museum collection. With 91 species belonging to 25 genera added to collection lately, it made more than 7000 specimens of 476 species from three classes of helminthes, including the type materials. Recently the systematic collection of Trematoda (18 families, 93 genera, 268 species, 1763 units of storage) has been established.

Analysis of specific diversity of metacercaria diversity in the Caspian Sea published in monographic series "Metacercaria of Trematoda, parasites of hydrobionts in Russia", has shown that majority of the Caspian trematode species originated from fresh waters.

Studies on entomopathogenic nematodes of the families of Steinernematidae and Heterorhabditidae have been carried out for about 30 years. Invasive juveniles of these nematodes are used now widely as biocontrol agents. Phylogenetic analysis of the Steinernema revealed a presence of several evolutionary lines, well defined both by molecular and morphological features. New data on the spatial distribution of entomopathogenic nematodes were obtained during the field surveys in Belgium (in cooperation with Institute of Agricultural and Fisheries Researches) and in Scotland (in cooperation with Aberdeen University).

The sequence data were obtained for several taxa of nematodes parasitic in invertebrates for the first time and used for phylogenetic analyses. Based on molecular data, phylogenetic relationships between two higher taxa of parasitic nematodes within Rhabditia (Secernentea): the superfamily Drilonematoidea and the order Rhigonematida, were analysed. Close phylogenetic relationships between free-living cephalobid nematodes and Dicelis nematodes (Drilonematoidea) parasitic in earthworms were revealed. Phylogenetic links between Ransomnematoidea (Rhigonematida) and free-living plectids were also demonstrated. Such findings are adding new facts to the understanding of parasitism acquisition among nematodes of subclass Rhabditia.