Morphometric and genetic analysis shows that Haliplus wehnckei is a juniorsynonym of H-sibiricus (Coleoptera : Haliplidae)

Specimens of the two nominal species Haliplus sibiricus Motschulsky, and H. wehnckei Gerhardt, were examined by enzyme electrophoresis and morphometri cal methods. Beetles collected from five different localities along the nor th Swedish coast were screened at ten different loci, and paramere shape va riation was studied using Elliptic Fourier description. Wright's F-statisti cs were computed to assess population structure, and PLS-analysis (Projecti ons to Latent Structures modelling) to estimate shape differences. We revis e the distribution of the two species in Sweden. The results show a gross o verlap and sympatry. Paramere shape analyses indicate the existence of two different forms, which change in frequency with latitude. There are morphol ogically intermediate specimens that would be difficult to place into eithe r species. Genetic data do not support the nominal species status, and F-ST -values indicate moderate genetical differences between the populations. We propose that H. sibiricus and H. wehnckei are conspecific. They are either subspecies, or represents two different morphotypes of a clinally varying character. Our data support the latter. Accordingly, H. wehnckei Gerhardt, 1877, is a junior synonym of H. sibiricus Motschulsky, 1860, syn. n.