MORPHOMETRIC ANALYSIS AND PHASE STATE ASSESSMENT OF AN ASIAN LOCUST POPULATION IN THE SLAVYANSKY DISTRICT OF KRASNODAR KRAI

An assessment of morphometric characteristics and phase status was conducted on a natural population of the Asian migratory locust (Locusta migratoria migratoria L.) in the Slavyansky district of Krasnodar Krai, one of the key areas of its reservation. A sample of 201 adult individuals (114 males and 87 females) was analyzed. Four key morphometric parameters were measured: elytron length (E), hind femur length (F), pronotum length (P), and head width (C). Based on these measurements, classic phase indices (E/F, F/C, and P/C) were calculated to reflect the degree of gregariousness of individuals. Pronounced sexual dimorphism was established, with females being statistically significantly larger than males in all absolute measurements. Analysis of the phase indices revealed significant population heterogeneity. Based on the F/C ratio, the majority of individuals (approximately 60 %) exhibited characteristics of the solitary phase. In contrast, the E/F and P/C indices showed a mixed picture, with a predominance of solitary and transient phase individuals but with a substantial proportion (13-30 %) of individuals showing distinct gregarious phase traits. The comprehensive analysis indicates that the population is generally in a low-density state (predominantly solitary phase) but contains a significant pool of individuals with high potential for gregarization. These findings are critically important for the phytosanitary monitoring system, as they indicate persistent risks of mass outbreak formation in the region.