The main goal of this study was to predict, through the use of GIS tool as ecological niche modelling, potentially suitable ecological niche and defining the conditions of such niche for the representatives of the cosmopolitan genus Sirthenea. Among all known genera of the subfamily Peiratinae, only Sirthenea occurs on almost all continents and zoogeographical regions. Our research was based on 521 unique occurrence localities and a set of environmental variables covering the whole world. Based on occurrence localities, as well as climatic variables, digital elevation model, terrestrial ecoregions and biomes, information about the ecological preferences is given. Potentially useful ecological niches were modelled using Maxent software, which allowed for the creation of a map of the potential distribution and for determining climatic preferences. An analysis of climatic preferences suggested that the representatives of the genus were linked mainly to the tropical and temperate climates. An analysis of ecoregions also showed that they preferred areas with tree vegetation like tropical and subtropical moist broadleaf forests biomes as well as temperate broadleaf and mixed forest biomes. Therefore, on the basis of the museum data on the species occurrence and ecological niche modelling method, we provided new and valuable information on the potentially suitable habitat and the possible range of distribution of the genus Sirthenea along with its climatic preferences.

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1 Sipha (Rungsia) maydis, Sipha (Rungsia) elegans, Sipha (Sipha) glyceriae and especially Sipha (Sipha) flava are considered to be virus vectors and serious pests of crops and pasture grasses. Ecological niche modelling, a useful tool for assessing potential geographical distributions of species, was used to predict the risk of invasion of these four species of the Siphini (Hemiptera, Aphididae) on a global scale. 2 The maximum entropy model based on associations between unique occurrence localities and a set of environmental variables was used. Obtained models of potentially suitable habitats, based only on climatic variables, suggest that favourable conditions for each species may be present on every continent. However, S. (S.) flava appears to be potentially the most widespread species. Moreover, the resulting maps provide important information on the corridors by which invasive species are able to penetrate into new areas. 3 A mean of the area under the receiver operating characteristic curve at the levels of 0.937, 0.947, 0.968, 0.937 for S. (R.) maydis, S. (R.) elegans, S. (S.) glyceriae and S. (S.) flava, respectively, indicated a high level of discriminatory power of the maximum entropy model. 4 A jackknife test indicated that the precipitation of the coldest quarter with the highest gain value was the most important environmental variable restricting the expansion of the studied species.

Background: The redescription of Platymeris rhadamanthus Gerstaecker, 1873 as well as the designation of lectotype and paralectotype, plus the prediction of the potentially suitable habitat was the main goal of this study. Our research were based on 262 specimens of museum collections of P. rhadamanthus species and a set of 23 environmental predictor variables, all recorded in a 1x1 km grid covering Africa. Ecological niche modelling was performed using the MAXENT analyses to produce predictive potential distribution maps for this species and its colour forms separately. Results:The results suggested the most suitable areas of distribution of P. rhadamanthus, both for species as a whole and also for the colour forms. A jackknife test showed that the precipitation of coldest quarter and herbaceous vegetation were the most important environmental variables affecting the distribution of P. rhadamanthus. After analyzing the climatic preferences, this species seems to be related mainly to the tropical savanna climate, subtropical highland variety of the oceanic climate and humid subtropical climate. An analysis of environmental variables also showed that this species prefers areas with herbaceous vegetation, with a small participation of trees, which is probably caused by food preferences of its victims.

During our previous morphological and molecular studies, as well as modelling the environmental niche preferences of the genus Sirthenea Spinola, 1840 (Peiratinae), the distribution of the species S. flavipes (Stål, 1855) became one of the most interesting issues. This species has a very broad distribution range covering the southern part of western, central and eastern Asia. We observed two distinct types of colouration, each also exhibiting a certain degree of variability. Although both colour forms of the studied species show similar variability, the differences between them are so clear that they allow distinction of two populations that are separated by a geographical barrier. Morphology and colour variability are described for representatives of both populations. Genetic studies support the use of the distributional model for individuals in both populations, as well as a characteristic distribution of colour forms. Models which identified potentially suitable habitats based solely on climatic variables are prepared for both populations, as well as for the entire species, and predicted for the Last Glacial Maximum period. An analysis of ecoregions shows that both populations prefer areas with tree vegetation, such as tropical and subtropical moist broadleaf forest biomes. Our studies show morphological divergence of these two discrete populations, reflecting an incipient stage of speciation.