Data on the distribution and habitats of Carabus hungaricus Fabricius, 1792 in Volgograd Province are reported and compared with those on the species’ distribution and abundance in the neighboring regions. Along the catena profile including a crop field, a forest shelter belt, upland zonal steppe areas, slopes and thalweg of a shallow steppe gully, the majority of C. hungaricus adults concentrated along the thalweg and on the north-facing slope of the gully. The maximum population density was observed in September, apparently due to the emergence of adults of the new generation. The numbers of C. hungaricus in the study area have multiplied tenfold since the 1980s and then only insignificantly increased during the first 20 years of the 21st century. Such a population increase was probably caused by transition to closed irrigation systems, which ended the discharge of irrigation water into the gully in 1994–1995.

A total of 29 species of entomophagous insects from 15 families of 4 orders were found for the first time in the galleries of the small spruce bark beetle Ips amitinus within its invasive range in West Siberia; 26 species were predators of Ips amitinus, including 11 species of obligate and 15 species of facultative zoophages. The most abundant obligate predators were Thanasimus femoralis (Zett.) (Coleoptera, Cleridae) and Medetera fasciata Frey (Diptera, Dolichopodidae); the most abundant facultative predator was Placusa complanata Er. (Coleoptera, Staphylinidae). The larval ectoparasitoids Dinotiscus eupterus (Walk.) and Rhopalicus tutela (Walk.) (Pteromalidae) and the endoparasitoid of adults Ropalophorus clavicornis (Wesm.) (Braconidae) develop on I. amitinus both in its native range and in the secondary ranges. Widespread representatives of the local fauna that have established new trophic links with I. amitinus absolutely predominate among its entomophages in West Siberia. The European species Phloeonomus sjoebergi A. Strand (Staphylinidae) and Epuraea dolosa Kir. (Nitidulidae) were found for the first time in Siberia. Ips amitinus has been included in the prey spectrum of Medetera penicillata Neg., which is an obligate predator of Polygraphus proximus Blandf., another invasive bark beetle of Far Eastern origin.

Two new species of the genus Phaeophilacris Walk., belonging to the tribe Phalangopsini, as well as a new subtribe, genus, and species of the tribe Paragryllini, are described from tropical Africa: Phaeophilacris (Araneacris nom. n.) multa sp. n.; Ph. (Paeophilacris) rara sp. n.; Paragryllodina subtrib. n.; Ugandacla sylvestris gen. et sp. n. A few changes are introduced into the key to the genera and subgenera of Phaeophilacridina. Some other African representatives of Phalangopsinae are also briefly discussed.

Body size is one of the important parameters that determine the biology, morphology, and physiology of animals. Despite their diminutive body size, the smallest insects retain the general structure, functionality, and diversity of their sense organs. The main sense organs of insects are compound eyes and antennal sensilla, which have been studied in a wide range of taxa. The size of the antennae and the number of antennal sensilla decrease considerably with body size. The size reduction of compound eyes is accompanied by some quantitative and structural changes: a decrease in the number and size of the facets, strong compaction of cellular elements, and various morphological adaptations unique to different insect taxa. Our review consists of two parts and includes not only coverage of the available literature on scaling of the sense organs in insects, but also analysis of the basic quantitative data on the insect vision organs and antennal sensory systems. The first part presented herein includes the general characteristic of the sense organs and an overview of the effects of scaling on the insect compound eyes. A unique database has been created, including data on the number and size of the compound eye facets in 370 species from 16 orders of insects. Allometric analysis has shown that the number of ommatidia in the compound eye is positively correlated with body size and is considerably reduced in smaller insects. The corresponding numbers differ by up to three orders of magnitude between larger and the smallest insects. The linear size parameters of the ommatidia are also correlated with the body size, the values differing by an order of magnitude. The complex morphology of composite sense organs seems to limit the size reduction of individual sensory units, so that optimization of the sensory apparatus in miniature insects is primarily accomplished by reducing the number of structural elements.

Larval morphology is described for seven species of horseflies (Diptera, Tabanidae) of the Hybomitra (s. str.) bimaculata Macq. group: Hybomitra bimaculata (Macquart, 1826), H. ciureai (Séguy, 1937), H. distinguenda distinguenda (Verrall, 1909), H. lundbecki lundbecki (Lyneborg, 1959), H. lurida (Fallén, 1817), H. muehlfeldi (Brauer, 1880), and H. nitidifrons confiformis (Chvála et Moucha, 1971). Some differences from the previously published data are noted as concerns external morphology and the structure of the head capsule and mouthparts in the examined species. For example, a chaetoid field was found on the preanal and anal segments in H. lurida. The lateral grooves are absent and the dorsoventral grooves are poorly developed in Hybomitra n. confiformis. The details of mouthpart structure completely coincide with those described in the literature only for H. muehlfeldi, while the six remaining species reveal some differences. A detailed study of the submentum has shown that its structure can be used as an additional diagnostic character. The larvae of all the examined species clearly differ in the length ratio of the submentum notch and the submentum itself. The submentum of H. muehlfeldi larvae differs from that in other species in the degree of chitinization of the anterior end around the notch.

Seasonal development of Molipteryx fuliginosa (Uhler) in Primorskii Territory, including the timing of oviposition and development until the emergence of adults, was studied during 6-year monitoring under natural and seminatural conditions. The species has a univoltine seasonal cycle. Eggs are laid randomly on various substrates, including the ground. The embryonic stage lasts from 12 to 36 days, depending on the air temperature. The development of nymphs from hatching to the final molt lasts from 55 to 83 days. The total duration of preimaginal development varies from 80 to 117 days. The optimal conditions and timing of seasonal development of M. fuliginosa in nature were determined.

Data on 15 species of leaf beetles found in the southern steppe and semi-desert landscapes near the boundary between Europe and Asia (Orenburg Province) outside their previously known ranges are reported. Twelve species are recorded for the first time for Orenburg Province and for the Ural region as a whole: Crioceris bicruciata, Labidostomis metallica metallica, Cryptocephalus kerzhneri, C. tataricus, Pachybrachis vermicularis, P. cribricollis, Stylosomus flavus, Chloropterus versicolor, Phyllotreta sholaksori, Chaetocnema major, Ch. nebulosi, and Cassida parvula. Of these, Cryptocephalus kerzhneri is for the first time recorded in Russia, and Phyllotreta sholaksori, recently described from the steppe zone of Omsk Province, is for the first time found in the Steppe Trans-Urals. The records presented here supplement my previous data, which testify to the presence of an important zoogeographic boundary passing through the very south of Orenburg Province within 51.00–51.50°N, from the Obshchy Syrt to the Turgai Plateau. To the south of this boundary the fauna of phytophagous beetles includes many species characteristic of the semi-deserts and deserts of Kazakhstan and the Caspian region, these species comprising a considerable proportion of the fauna.

The state of the natural foci of tick-borne encephalitis (TBE) was monitored during 15 seasons (2005–2019) in several key plots within a popular recreational and tourism area along Highway 25K-011 Irkutsk–Baikal. The populations of the virus and its main vector, the taiga tick Ixodes persulcatus, were shown to be in a stable state. The studied plots varied strongly in the density of adult ticks and in its multi-year and seasonal dynamics. Spatial and temporal variations in the tick infection rate were detected, but no specific trend over the study period was observed. The multi-year density dynamics of the vector did not correlate with that of its infection rate. A significant role of the taiga tick males in dissemination of the TBE virus has been highlighted.

The Eastern Caucasian highland natural plague focus is located on the northern slope of the Main Caucasian Range. This peculiar region has a rich fauna of rodent fleas comprising 32 species of 17 genera. Most flea species occur on a wide range of rodents from different subfamilies but belonging to the same ecological group. Fleas of 26 species are distributed throughout the longitudinal extent of the East Caucasus northern slope. Three species inhabit the Samur and Sulak river basins and have not been found in more western areas despite the presence of suitable hosts there. Three more species are confined to the westernmost part of the East Caucasus. The warm season is the most favorable period for plague transmission due to high gonotrophic activity of most flea species associated with the common vole.

Data on two little known weevil species from the Sayano-Shushenskii State Biosphere Reserve (West Sayan Mountains) are reported and three new species of the Phyllobius subgenus Angarophyllobius are described: Phyllobius (Angarophyllobius) shikalovae Korotyaev, sp. n. and Phyllobius (Angarophyllobius) ryvkini Korotyaev, sp. n. from the nature reserve, and Phyllobius (Angarophyllobius) makarovi Korotyaev, sp. n. from the adjacent territory of western Tuva.