Specimens of Spinitectus osorioi Choudhury and Pérez-Ponce de León, an intestinal nematode species previously considered to be specific to Chirostoma spp and endemic to some lakes in the Pacific drainage in Michoacán, were collected from the freshwater fish Atherinella alvarezi (Díaz-Pardo) (Atherinopsidae) of the Michol River near Palenque, Chiapas, Southern Mexico, which belongs to the Atlant...

New species of the rarely encountered megachilid genera Afroheriades Peters from South Africa, Afroheriades hyalinussp. n., and Noteriades Cockerell from Myanmar and Thailand, Noteriades jenniferaesp. n. and Noteriades spinosussp. n., are described and illustrated. The species are described to make their names available for forthcoming publications on phylogenetic studies of the family Megachil...

We highlight the increase in the number of diatom genera being described, and suggest that their description be based on the concept of monophyly. That is, a new genus will contain the ancestor and all its descendants. Past criteria or guidance on how to circumscribe genera are reviewed and discussed, with conceptual and actual exemplars presented. While there is an increase in the rate of genu...

Salinities in some normally-closed estuaries in the central south coast of Western Australia are now frequently becoming highly elevated. This is due to: (1) high evaporation rates in water volumes that, by summer, are already low as a result of atypically dry winters; and (2) increased salt run-o¡ following vegetation clearing in the catchments. A few black bream (Acanthopagrus butcheri) died ...

Parasitoid-induced mortality of house fly, Musca domestica L., pupae and parasitoid progeny emergence by four species of pteromalid parasitoids, Muscidifurax raptor Girault & Sanders, M.zaraptor Kogan & Legner, Spalangia cameroni Perkins and S.endius Walker, were determined for a 24 h exposure period using parasitoid: host ratios ranging from 1:2 to 1:50. When the number of parasitoids was held...

m(x) = Wni(x ; X1 , . . . , Xn)Yi, i 1 and Wni(x; X1 , . . . ,Xn) is 1/k ifXi is one of the k nearest neighbors of x among X1, . . . , Xn , and Wn i is zero otherwise . Note in particular that I' 1 W,1 = 1. The k-nearest neighbor estimate was studied by Cover (1968) . For a survey of other estimates, see, for example, Collomb (1981, 1985) or Gyorfi (1981) . We are concerned with the L1 converge...