Are we witnessing speciation? A case study of the species Sirthenea flavipes (Stål, 1855) (Heteroptera: Reduviidae)

Abstract

AbstractDuring our previous morphological and molecular studies, as well as modelling the environmental niche preferences of the genus Sirthenea Spinola, (Peiratinae), the distribution of the species S. flavipes (Stål, ) 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.