Up to the present, the largest type collections are represented for the following taxa:
Trombiculid mites - about 200 species described by N.I. Kudryashova and E.H. Shluger.
Millipedes - more than 200 species described by S.I. Golovach, E.V. Mikhalyeva, V. Sher (all are diplopods), and by A.A. Shileyko, Jr (chilopods).
Chelicerata - more that 650 species (mostly spiders) described by many authors.
Tanaid crustaceans - 63 species described by R.K. Kudrina-Pasternak.
Cirripedes - 63 species described by G.B. Zevina, M.P. Memmi, S.V. Galkin.
Copepods - 31 species described by M.V. Heptner, E.A. Streletskaya.
Isopods - 139 species described by several authors.
Decapods - 55 species described by many authors; there are also paratypes obtained by exchange from other museums in Europe and N America.
Mollusks - there are about 600 specimens of species allocated to 6 classes, including nomenclatorial types (holotypes, lectotypes, syntypes) of 260 species. Of them, there are types of about 430 species of gastropods.
Besides, there are isolated type specimens of nearly all major invertebrate phyla.
Arachnoids
The oldest part of arachnological collection of the Museum contains specimens of spiders (600 specimens) and harvestmen (70 specimens) from Western Europe, predominately from France. They were purchased from W.S. Rosengauer (Wien) in the 1860s. A collection of 220 specimens of spiders from Australia and Oceania identified by acknowledged arachnologist L. Koch, Jr. was obtained from Godefroi Museum in Hamburg.
The first large collection of spiders from territory of Russian Empire was brought by A.P. Fedchenko from Turkestan in 1875. It contains about 1.200 specimens, including types of 30 species, and was studied by A.I. Kroneberg.
Earlier curators of arachnological collection were P.R. Freiberg (1890s), N.S. Grese (1910s), and V.I. Pereleshina-Sychevskaya (1920s). They dealt with extensive spider collections from Central Russia mainly donated by Society of Amateurs in Natural History, Anthropology, and Ethnography. The large part of these collections appeared to be dried up and was recently soaked in the lactic acid by K.G. Mikhailov.
One of the essential entries of the first half of XX century was a collection brought by Pereleshina from Kamchatka in 1930. It contains more than 1.500 specimens including representatives of some rare species and the types of several newly described ones.
Inflow of the materials became more intensive in the 1980s when Mikhailov became curator of arachnological collection. Type series of more than 400 spider species came to the Museum. Extensive sample collected by S.K. Alekseev in North Osetia was acquired in 1985-1986. In total, the collection of spiders includes now more than 20.000 items, or about 200.000 specimens.
Taxonomic composition of this collection is uneven. The most represented are the families Clubionidae, Salticidae and Linyphiidae which are most numerous in the FSU fauna. Families Gnaphosidae, Thomisidae s.lato and Araneidae are also worthy of being mentioned as quite numerous.
Geographically, most extensive samples came from Central Russia, Middle Volga Basin, Caucasus, Turkmenia, Southern Kazakhstan and mountains of Middle Asia, while Crimea is less represented. Yamal and Taimyr Peninsulae, Polar Ural, Altai Mts, Yenissei River are most represented among Siberian regions, while Chukotka, Kamchatka, Sakhalin Isl., and Kuril Isls. are best covered among collections from Far East.
There are also noteworthy recent acquisitions from Vietnam and Pacific, from Seychelles. Unfortunately, Africa, South America and Australia are not represented in the spider collections of the Museum.
Since the 1980s, all the spider collection is arranged taxonomically by families, and species within each family are arranged alphabetically.
Collection of the harvestmen (order Opiliones) is not extensive and contains mainly materials from Western Europe acquired in middle of XIX century and from Moscow Government came at the beginning of XX century. More recent is not numerous but interesting collection from some tropical regions in Asia, Africa and America. Materials from Ural and Siberia have been coming regularly since the 1990s.
Among pseudoscorpions, of special interest are types of two species of the cave fauna of Caucasus described by I.I. Laptev. Extensive samples (more than 2.000 specimens) were coming during last decades from Caucasus and other regions of the former USSR.
Collection of the scorpions is not large. Several specimens acquired in the 1860s and representing West Europe, America and Australia are to be mentioned first. There are also specimens from North Africa and Near East. Materials that came from Middle Asia in the 1980s are more extensive.
The phalanxes are rather scanty in the collection, mainly from Caucasus, Middle Asia and the Mediterranean. There are type series of 4 species decried from territories of Soviet Union and Iran.