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Three new Ptychoptera Meigen, 1803 species from southern China, P. hekouensis sp. nov., P. longa sp. nov., and P. xiaohuangshana sp. nov., are described and illustrated. These new species are mainly distinguished from congeners by their body colors and male genitalia. The genus Ptychoptera is recorded from Guangdong, China for the first time. An updated key to all Chinese Ptychoptera species is provided. [ABSTRACT FROM AUTHOR]

The western flower thrips (WPT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), an invasive insect pest in China, causes great economic losses worldwide. To understand the effects of heat shock on WFT population dynamics, we constructed life tables to quantify the effects of heat shock on the growth rate, survival, and fecundity of WFT offspring. WFT adults and 2nd instars were heat shocked at 45 °C, and the treatment was repeated after a 24-h recovery period. Heat-shocked and control insects were reared on the leaves of purple cabbage (Brassica oleracea L.; Brassicales: Brassicaceae), and various lifetable and development parameters of their F1 offspring were evaluated. The duration of the immature period of the offspring of heat-shocked adults was not significantly shorter than that of the control, whereas the duration of the immature period of the offspring of the heatshocked 2nd instars was longer than that of the other treatments, indicating that heat-shock of second instars slowed the development of their offspring. The preoviposition period during the adult stage and the total oviposition period of the F1 offspring of the heat-shocked adults were significantly longer than those of the control. The fecundities of the F1 offspring of the heat-shocked 2nd instars and adults were 81.8 and 70.6 eggs/female, respectively, both of which were significantly less than that of the control (149.1). The use of heated tents might be effective for the prevention and control of WFT infestations in greenhouses. Our life-table analysis of the effects of heat shock on F1 survival and reproduction provides a strong basis for future studies of thermal treatments for the control of WFT. [ABSTRACT FROM AUTHOR]

Abstract: The provenance of Chinese Loess Plateau sediments is an often-posed question that has not been satisfactorily resolved. Elemental geochemistry characteristics of the deposition may provide important evidence in this regard. To this end geochemical analyses were undertaken on densely sampled strata from four loess sections (one of which is located in Northwestern China at the desert margin and the other three on the Loess Plateau) as well as sediments from the Badain Jaran Desert. It was found that loess deposition on the Chinese Loess Plateau and the northern foot of the Qilian Mountains had strong geochemical similarity during the last glacial cycle, but had remarkable differences with the Badain Jaran Desert samples. It is inferred that the desert was not the most important direct provider of dust material to the Loess Plateau. Rather, one of the main source areas appears to have been the vast silt-rich piedmont alluvial fan distributed at the northern foot of the Qilian Mountains. [Copyright &y& Elsevier]