Biological species

usually under B.s. or simply species it is understood a population, or variety of populations, of species which are able to crossbreed forming a fecund produce (without reduction of fertility) possessing a number of common morphophisiological features and detached from other alike groups of species with almost entire absence of the hybrid forms. B.s. is a basic structural unit in a system of living organisms, a qualitative stage of evolution. In context of Obliganto asexual (agamic), parthenogenetic and self-impregnating organisms under B.s. there are understood groups of alike clones (produces of one organism) or lines possessing a genetic and morpho-physiological analogy, occupying a certain areal and having a similar type of interrelations with habitat.