Population genetic structure among populations of three predaceous nabid species: Nabis alternatus Parshley, Nabis roseipennis Reuter and Nabis americoferous Carayon (Hemiptera: Nabidae)

An electrophoretic survey of 28 presumptive loci distributed among 15 enzyme systems was conducted to determine the genetic structure among local populations of three predaceous nabid species: Nabis alternatus, N. roseipennis and N.americoferous in human-disturbed habitat. For all three species, F_IS values indicated a deficiency of heterozygotes at most loci in most populations. The amount of genetic differentiation based on the standardized variance, F_ST when combined across all poulations was 0.100 for N. alternatus, 0.189 for N. roseipennis, and 0.335 for N. americoferous. When local populations were grouped according to a set of defined geographical limits, based on the naturally occurring spatial arrangement of the sampled localities, some unexpected patterns of genetic variation were revealed. The degree of genetic differentiation detected among local populations of nabids is discussed in light of the frequent disruptions and ecological changes in their ephemeral habitats.