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This paper aims to re-describe and illustrate the poorly known grasshopper Podismopsis insularis and to clarify the taxonomic status of its subspecies. This species occurs on all large islands of the Shantar Archipelago (Bolshoi Shantar Island, Feklistova Island, and Maly Shantar Island). The type specimens of both subspecies and additional material are examined. A new synonymy is established: Podismopsis insularis = Podismopsis insularis shantariensis, syn. nov. A thorough description of this species, photographs of male and female habitus and of male genitalia are also provided. The evolutionary radiation of grasshoppers of the genus Podismopsis over the islands of the Sea of Okhotsk basin during the last 8000–10 000 years is briefly discussed. The Shantar Islands National Park is important for conservation of endemic insect species.

Eighty six species of grasshoppers belonging to 11 subfamilies and 3 families are recorded for the Ciscaucasia. Paracinema tricolor (Charpentier, 1825), Stenobothrus stigmaticus (Rambur, 1838) and Omocestus minutus (Brullé, 1832) are recorded for the region for the first time. Limits of distribution in the region are established for Stenobothrus miramae and Acrotylus longipes, firstly recorded in 2016. The distribution of grasshoppers by the main physical-geographical areas of the Ciscaucasia is shown. The highest diversity of grasshoppers is registered for the Eastern Ciscaucasia, where 63 species are recorded, 20 ones (23.3% of the total number of species) of which were found only in the region, that indicates the faunistic specificity of the territory. Fifty four species of grasshoppers are recorded for the Central Ciscaucasia. High similarity of faunas in the Terek-Sunzha Hills and Mineralnye Vody laccoliths can be explained by the pervasion of mountain elements from the North Caucasus. High similarity of grasshopper faunas is observed also between different areas of the Western Ciscaucasia, where 45 species are registered. Life forms of grasshoppers, such as gramineous chortobionts (32 species, 37%), eremobions (18 species, 21%) and facultative chortobionts (17 species, 20%) are most abundantly represented in the Ciscaucasia. Grassfeeding chortobionts are observed exclusively in the Western Ciscaucasia, while psammobionts are distributed only in the Eastern Ciscaucasia. The number of geophils in the Ciscaucasia regularly increases from the west to the east with increasing landscape aridization. Eremippus opacus is the only endemic of the Ciscaucasia; Stenobothrus caucasicus is an endemic of the North Caucasus; Asiotmethis turritus and Nocarodes geniculatus are two subendemic species in the North Caucasus.

Sixty one species of grasshoppers from 35 genera and 8 subfamilies are recorded for the North-West Caucasus. The features of biotopic distribution of grasshoppers are analyzed on the main types of landscapes in the region. In the Kuban – CisAzov biogeographic province, the highest diversity of grasshoppers is characteristic of steppe biotopes with forb-grass vegetation, where 25 species are noted. The highest diversity is typical for low-mountain meadows and mountain steppes, which number 22 grasshoppers species each in the Black Sea – Kuban province. At the same time, these landscapes are characterized by a low value of the measure of similarity of Sørensen-Chekanovsky (0.51). Gramineous chortobionts (52%) and facultative chortobionts (16%) dominate in the fauna of the NorthWest Caucasus, the remaining life forms of grasshoppers are represented by a relatively small number of species. Among the grasshoppers, seven endemic species for the North-West Caucasus, as well as two endemic species for the whole Caucasus, are noted.

The presence of the grasshopper Chorthippus brunneus brevis (Orthoptera, Acrididae, Gomphocerinae) has been confirmed for the Vyborg district mainland of the Leningrad region, Russia, for the first time since 1908. Information about its habitats, characteristics of morphology, as well as calling signals of males is presented. The differences of the stridulatory file structure in the males of the closely related species Ch. brunneus brunneus, Ch. brunneus brevis and Ch. porphyropterus from the territory of Russia are considered. Information on the difference in calling of both subspecies of Ch. brunneus is given.

36 grasshopper species were showed for environs of the Dzhanybek Research Station. Features of their phenology and biotopical preference were investigated. Structure of grasshopper communities in common types of biotopes is discussed. Calling songs of 20 species of the subfamily Gomphocerinae are described. It is shown that species inhabiting the same biotope could have strong overlap of food and microhabitat niches, but they have different acoustic niches. In some cases, interspecific competition for the acoustic dimension of the biotope is important factor limiting biotopical distribution of grasshoppers

The Argiope lobata venom is shown to block synaptic potential at locust neuromuscular junctions and inhibit the high-affinity sodium independent L[3H]glutamate binding site in locust muscle membranes. The data obtained due to fractionation of venom evidence that it contains components which block synaptic potential and inhibit the binding of L[3H]glutamate (5 kDa and more) as well as components which block synaptic potential but do not inhibit the binding of L[3H]glutamate less than 5 kDa. These observations indicate that spider venom contains at least two components with different mechanism of action.

The manifestations of predatory aggression in response to placing a locust or a cricket nearby was studied on male mice of 12 inbred lines. Predatory aggressiveness was estimated by latency of the attach reaction and the percentage of aggressive mice in each line. Significant interlinear differences were established both in attach latency and in the number of killers. Significant negative correlation was found between the percentage of attacking mice in each line and the latency of the attack. Predatory aggressiveness of the mice increased with experience of attacking, the attack latency considerably decreasing at repeated testing. The number of mice attacking the insects increased with their repeated presentation in the first test 50% of tested mice attacked the locusts, and 76% in the second. The manifestation of predatory aggressiveness differently depends on the species of the victim, mice of different lines attack differently the locust and the cricket.

The study was devoted to the influence of serotonin (5-HT) on the mice predatory aggression towards locusts which was estimated by the latency of attack and the number of aggressive mice in the experimental group. 10 mg/kg of 5-HT injected intraperitoneally, significantly decreased the percentage of aggressive mice and prolonged the attacks latency. 5-Hydroxytryptophan (5-HTP), 5-HT precursor, had a more prominent inhibitory effect which was significant when the dose amounted to 50 mg/kg. Imipramin, an inhibitor of 5-HT reuptake, diminished predatory aggression in dose-dependent manner. Pretreatment of metisergid (blockader of 5-HT receptors) prevented the inhibitory effect of 5-HTP. 5-HT suppressing influence on mice predatory aggression is due by its action on central mechanisms as the injection of small doses of 5-HT in the mice lateral ventricle considerably decreased their aggression towards locusts.

Some present-day conceptions on the structure and physiochemical and functional properties of mitochondrial ribosomes of higher and lower eukaryotes are reviewed. Mitochondrial ribosomes are compared to the ribosomes of prokaryotic and eukaryotic types and plastid ribosomes; biogenesis and functions of mitochondrial ribosomes are also discussed.

On muscle fibers from m. flexor tibiae of the locust studies have been made of the effect of rapid changes in potassium and chloride concentrations on the membrane potential (MP). The MP constituted 56.0 +/- 1.0 mV. The relationship between the MP and the external potassium at [K]o.[Cl]o equals const may be described by Nernst equation for two different intracellular concentrations of these ions, at [K]o less than or equal to 40 mM and at [K]o greater than or equal to 80 mM. From the relationship between the MP and rapid changes in [K]o or [Cl]o at constant concentration of correspondingly [Cl]o and K]o relative membrane conductivity for these ions were found (TK=0.55 and TC1=0.41). Using impulse analysis, electrical constants of muscle membrane were determined (lambda = 1.9 +/- 0.1 mm; Ri equals 103 +/- 7 ohm.cm; Rm = 1.430 +/- 76 ohm.cm2; Cm = 16 +/- 1 muF.cm-2). High values for Cm correlate with numerous invaginations in muscle membrane which were revealed in electron microscopis investigations. Active responses of the membrane are gradual. In the presence of ions of Sr they are transformed into regenerative action potentials.

The amount of individual fractions in the whole histone isolated from the blood of hen, frog (Rana ridibunda), bream (Abramis brama), from rat thymus and from the locust (Schistocerca gregaris) was studied quantitatively. It is shown that the ratios between fractions F2a1, F2b, F2a2 and F3 are fixed. The share of each fraction in the sum of fractions F2a1, F2b, F2a2, F3 was found to be approximately 22.5, 30.5, 21.0 and 26.0 per cent, respectively. The share of the fraction F1 can variate within a rather wide range.

The distribution of ATPase activity in the flight muscle of Locusta migratoria L. was studied at the fine structural level after a brief fixation in formaldehyde or in glutaraldehyde. In both the cases, the final product of reaction -- fine grained electron dense precipitation--was clearly revealed in intact contractile muscle structures. The glutaraldehyde fixation provides a good preservation of all the ultrastructural components of muscle cell, and reveals deposites of the final product in sarcomeres at the resting length. However, after the glutaraldehyde fixation it is very difficult to recognize regions of fibrillar reaction on electronmicroscopic preparation. The formaldehyde fixation does not provide a good preservation of membranous structures. However after the formaldehyde fixation reacting regions are more extensive than after glutaraldehyde fixation, and, moreover, it is possible to demonstrate a correlation between the activity and the contraction of sarcomere.