Relation between the size of the above-ground and the underground phytomass of plant communities in the region of Gurwan-Turuu in Central Mongolia

Results are presented of measurement of the above-ground and underground phytomass in six different plant communities on the area of the dry steppes of Central Mongolia. The relation was calculated between the above-ground and underground phytomass. This relation was found to be mostly constant under the local conditions (1 :34). This allows to adopt the "top/roots ratio" as a synthetic index of the vegetation structure in the aspect of zonal differentiation.

Current knowledge of Coleoptera (Insecta) from the Lowermost Eocene Oise amber

The paper provides an overview on fossil Coleoptera from the Lowermost Eocene Oise amber of the Paris Basin (circa 53 million years old). At present 45 beetle families have been found from this source. This fossil “fauna” has some peculiarities in comparison with other amber deposits. Some of these families are not recorded in older outcrops (Pselaphidae, Smicripidae, Coccinellidae, Ciidae). Some subfamilies and tribes of other groups have their oldest representatives recorded in Oise, i.e., Eurygeniinae (Anthicidae), Inopeplinae (Salpingidae), Trinodini (Dermestidae), Megatominae (Dermestidae), Attageninae (Dermestidae), Brontinae (Silvanidae), Synchitini (Zopheridae) and Opatrini (Tenebrionidae). The genera defined in the “Oise fauna” show various geographical links with relatives in the recent fauna. These alternative links support that the faunistic composition of the early Eocene had a weak zonal differentiation. Scirtes circumcisus sp.n., Boleopsidae fam.n., Boleopsis polinae gen. et sp.n. and Antiphloeus stramineus gen. et sp.n. are described. The synonymy of the genera Scirtes Latreille, 1796 and Eohelodites Hong, 2002 is proposed.