Parasite distribution patterns in lotic catchments are driven by the combined influences of unidirectional water flow and the mobility of the most mobile host. However, the importance of such drivers in catchments dominated by lentic habitats are poorly understood. We examined parasite populations of Arctic charr Salvelinus alpinus from a series of linear-connected lakes in northern Norway to assess the generality of lotic-derived catchment-scale parasite assemblage patterns. Our results demonstrated that the abundance of most parasite taxa increased from the upper to lower catchment. Allogenic taxa (piscivorous birds as final host) were present throughout the entire catchment, whereas their autogenic counterparts (charr as final hosts) demonstrated restricted distributions, thus supporting the theory that the mobility of the most mobile host determines taxa-specific parasite distribution patterns. Overall, catchment-wide parasite abundance and distribution patterns in this lentic-dominated system were in accordance with those reported for lotic systems. Additionally, our study highlighted that upper catchment regions may be inadequate reservoirs to facilitate recolonization of parasite communities in the event of downstream environmental perturbations.

A method for identifying the members of the endemic genus Wiseana Viette from New Zealand is described. Seven species have been described in the genus: W. cervinata (Walker), W. copularis (Meyrick), W. fuliginea (Butler), W. jocosa (Meyrick), W. mimica (Philpott), W. signata (Walker) and W. umbraculata (Guenée). No morphological characters have been identified to distinguish between the larvae of each species and adult females exhibit high levels of intra and interspecific morphological variation making identification difficult or impossible. Adult males can be distinguished by a combination of scale, antennal and genital characters, but this requires considerable taxonomic experience. Molecular markers were generated via amplification of the cytochrome oxidase subunit I and II (COI and II) of the mitochondrial DNA by the polymerase chain reaction (PCR). Amplified DNA was digested with restriction enzymes to give characteristic fragment patterns. Fourteen restriction enzymes were surveyed and a combination of four of these distinguish all Wiseana taxa except W. fuliginea and W. mimica.

Visible and far ultraviolet high resolution spectra of the B2 binary star HD 218393 have been obtained at one day interval, shortly before the phase of maximum outwards velocity, adopting the period of 38.908 days. Both spectra show the existence of an extended atmosphere, accelerated outwards. The SiIV resonance lines show some indication of mass loss. With only one set of observations, the origin of the strong and wide (about 130 km/s FWHM) ultraviolet absorption lines of once ionized elements is difficult to determine.