Asymmetric introgression between sympatric molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in the Comporta region, Portugal

Background  

Culex pipiens L. is the most widespread mosquito vector in temperate regions. This species consists of two forms, denoted molestus and pipiens, that exhibit important behavioural and physiological differences. The evolutionary relationships and taxonomic status of these forms remain unclear. In northern European latitudes molestus and pipiens populations occupy different habitats (underground vs. aboveground), a separation that most likely promotes genetic isolation between forms. However, the same does not hold in southern Europe where both forms occur aboveground in sympatry. In these southern habitats, the extent of hybridisation and its impact on the extent of genetic divergence between forms under sympatric conditions has not been clarified. For this purpose, we have used phenotypic and genetic data to characterise Cx. pipiens collected aboveground in Portugal. Our aims were to determine levels of genetic differentiation and the degree of hybridisation between forms occurring in sympatry, and to relate these with both evolutionary and epidemiological tenets of this biological group.     

Corrigendum: Renaming of Kimberia Dennis-Bryan & Miles, 1983

Mr Neville Pledge, Curator of Fossils at the South Australian Museum, has informed us that the name Kimberia which we used to describe a new genus of arthrodire from Gogo (Dennis-Bryan & Miles, 1983) is preoccupied by a gastropod. This was described by Cotton & Woods (1935) as a subgenus of Turritella Lamarck, the type species being Turritella (Kimberia) kimberi . We therefore propose to substitute the name Kimberleyichthys gen. nov. for the arthrodire.     

Morphogenesis of Schizophyllum commune III.Activity of inhibitors of energy metabolism

The effect of azide, 2,4-dinitrophenol, malonate and 2-deoxyglucoseon the physiology and morphology of normal and mutant strainsof Schizophyllum commune was studied. Normal, thin and puffstrains showed a decrease in dry weight and an increase in glucoseutilization in response to azide, dinitrophenol and 2-deoxyglucose.Streak was less sensitive to azide and dinitrophenol and almostcompletely resistant to 2-deoxyglucose. Numerous morphogeneticeffects were caused by the inhibitors. These included the inductionof certain aspects of the morphology of the common-A sexualreaction in normal and thin homokaryons by 2-deoxyglucose, areversion to normal morphology by thin strains in response toazide and dinitrophenol, and a morphogenetic insensitivity tothe inhibitors by the streak mutants. A discussion of the relationshipof these effects to the control of morphology in S. communeis given. ¹This investigation was supported in part by Research GrantAI-06570 from the National Institute of Allergy and InfectiousDiseases of the U. S. Public Health Service and by Grant No.GB-3613 from the National Science Foundation (U.S.A.). ²Present Address: Department of Biology, State College at Bridgewater,Bridgewater, Massachusetts 02324, U. S. A.     

A primitive eubrachythoracid arthrodire from Gogo, Western Australia

A new eubrachythoracid arthrodire, Hanytoombsia elegans gen. et sp. nov., is described from the Upper Devonian Gogo formation of Western Australia. Its structure and relationships are discussed within the framework provided by a new sketch cladogram for arthrodires. H. elegans is morphologically similar to Coccosteus cuspidatus , but its relationships among primitive eubrachythoracids are unknown.