Morphological variability is the result of interaction between genetic diversity of the population and environmental selection. Despite the large number of studies of morphological variability of ground beetles, there is very little research dedicated to influence of environmental factors on it. This article discusses the influence of natural and anthropogenic factors on the variability of Bembidion minimum (Fabricius, 1792). B. minimum is a West Palearctic species which is distributed in North Africa, Europe, Western Asia. It is a macropterous species that lives in humid biotopes along the shores of seas, rivers and standing water bodies. 410 specimens were collected from 12 ecosystems differing by plant cover, degree of litter development, mechanical composition of the soil, mineralization and acidity of soil solution, type and intensity of anthropogenic impact. 13 linear characteristics, one angular characteristic, density of elytra puncturing and contrast of spots on the beetles’ elytra were measured. Additionally 6 morphometric indices were calculated. More than a third of the variability of imagoes in the studied populations was found to be determined by the general body size. Sexual dimorphism was observed on all linear parameters and most morphometric indices. Females do not differ from males in the back angles of the prothorax. Natural and anthropogenic factors to a greater or lesser degree were shown to affect the morphological variability of B. minimum: soil acidity and mineralization have the greatest impact. The soil acidity causes significant variability of most linear parameters; mineralization – body length, head length, prothorax length and width, elytra width. Plant cover and mechanical composition of the soil have a slight impact on imago morphology. The type and structure of vegetation significantly affect head width, prothorax length and width, and the mechanical composition of the soil – body length and head length. Degree of litter development does not cause significant changes in the linear dimensions of beetles. With thickening of the litter the posterior spots on the elytra become brighter, they have sharper contours, and density of elytra puncturing also changes. The mean value of the back angles is affected by the herb layer of meadow vegetation, soil mineralization and acidity. The variability of morphometric indexes under the influence of natural factors was found to be lower than variability of linear characteristics. The recreational load and cattle grazing cause similar changes in linear measurements and morphometric indexes of B. minimum. With escalation of these factors, the body length, length and width of elytra of both females and males decrease. Assessing the natural morphological variability of populations in ecosystems whose environmental factors are within extreme and sub-extreme values for a given population is a promising direction of research in modern ecology.

Bembidion (Talanes) aspericolle (Germar, 1829) is a Western Palearctic species which lives on the shores of the Atlantic Ocean, the Mediterranean, Black and Caspian Seas and saline inland habitats from Central Europe to Central Asia. Anthropogenic impact is one of the most important environmental factors affecting the morphological variability of ground beetles. The objective of our research is assessment of the morphological variability of this species in three ecosystems differing by intensity of anthropogenic impact. 13 linear characteristics, one angular characteristic, density of pores on the prothorax and elytra, contrast of spots on the beetles’ elytra were measured, and 6 morphometric indices were calculated. The mean value of body length in females is more than in males in the studied populations. In the ecosystem with high anthropogenic pressure, female body length is shorter by 3.7% and elytra length is shorter by 6.0% than in females in the ecosystem with low anthropogenic impact. Differences between populations in the body length of males are not significant. In the ecosystem with high anthropogenic transformation, sexual dimorphism is observed only on head and prothorax width. The ratio of maximum width of elytra to maximum prothorax width decreases significantly with increasing anthropogenic load. The impact of anthropogenic factors on the ecosystem produces significant changes in elytra length and head width of B. aspericolle and in four of the six morphometric indices. It is reasonable to use these morphometric characteristics of B. aspericolle adults in bioindication. The complex of anthropogenic factors does not have a significant impact on the value of anterior and posterior angles of prothorax, density of prothorax and elytra puncturing and contrast of the light spots at the top of the elytra. The sex of the specimen influences all linear characteristics. The absence of significant differences in morphometric indices between males and females shows that the body proportions of the beetles remain unchanged and only linear dimensions vary. Research on the morphological variability of B. aspericolle is important for understanding microevolutionary processes in populations of beetles under anthropogenically induced changes in the environment.

This article discusses the effect of soil salinity on the variability of Bembidion (Notaphus) varium (Oliver, 1795). The authors of the article collected imagoes of this species in five ecosystems that differed in soil salinity; 13 linear characteristics, one angular characteristic and 6 morphometric indices were measured. Significant changes in six linear parameters of B. varium (body length, head length and width, width of prothorax between front angles, maximum width of prothorax and elytra width) and two morphometric indices are observed in the considered ecosystems. Soil salinity probably has the most impact on the variability of these characteristics. However, the influence of other important natural and anthropogenic factors is not ruled out. Significant differences between the sexes are observed for all linear parameters: females of B. varium are larger than males. There are no differences between males and females in morphometric indices. The head width, prothorax length and width, elytra length and width depend on the body length of B. varium individuals. The morphological variability of B. varium under the influence of other environmental factors needs further research.

Morphological variability can be used as an indicator of the state of invertebrate populations. Microevolutionary processes can show up in the morphological differentiation of populations. This includes differences between morphometric characters in the two sexes. The variability of 12 populations of Bembidion minimum (Coleoptera, Carabidae) was assessed by 24 morphometric characteristics and indices in this article. Bembidion minimum is a halophile that lives in ecosystems of Protected Areas in Ukraine (Black Sea Biosphere Reserve, Dniprovsko-Orilskyi Nature Reserve, Ornithological Sanctuary «Bulakhovsky Liman», Regional Landscape Park «Dniprovi Porogy», Samara Forest). The coefficients of variation for males, females, and combined populations of males and females were estimated in the article. The studied populations inhabited different soil and plant conditions and were under the influence of anthropogenic factors of varying intensity. The redundancy analysis shows three clusters. In the first cluster, morphometric characteristics and indices in both males and females were linked to environmental variables (herb layer, salt, composition of soil). The second cluster had morphometric characteristics and indices in both males and females with a link to environmental variables (pH, litter, recreational load, cattle grazing). The third cluster formed morphometric characteristics and indices in both males and females that are not affected by any environmental variables. The coefficient of variation for most of the linear morphometric characteristics of B. minimum (width of head, length of prothorax, width of prothorax, length of elytra and distance between setae on the elytra) for males was significantly lower than for the combined sample of males and females. The variability of width of elytra and length of body was significantly higher for females than for males. The degree of variability of males, females and their combined sample did not significantly differ for nonlinear morphometric characteristics, as well as for the six morphometric indices (body proportions) studied by us. In general, in the 12 studied populations of B. minimum, the coefficient of variation for most of the studied measurements was insignificantly lower in males (CV = 5.59%) than in females (6.10%) or in the combined sample of males and females (6.75%). The lowest variability in populations of B. minimum was found for morphometric indices: CV = 3.89% for males, CV = 3.76% for females, and CV = 3.86% for the combined population (males + females). The absence of differences in the mean values of the coefficient of variation between males, females and the combined sample of males and females for each individual population suggests that both males and females make a relatively equal contribution to the polymorphism of B. minimum populations. An assessment of the morphological variability of invertebrates, and especially the variation of coefficients of linear parameters and morphometric indices, can be used to indicate the state of ecosystems in Protected Areas in Ukraine and other countries.