Agasicles hygrophila Selman and Vogt (Coleoptera: Chrysomelidae) is a natural enemy of Alternanthera philoxeroides (Mart.) Griseb (Amaranthaceae: Alternanthera), a worldwide invasive weed. Elevated ...atmospheric CO.sub.2 concentrations may have significant impacts plants, herbivorous insects, and natural enemies.To assess the concurrent effect of elevated CO.sub.2 on the development time, fecundity, and population parameters of A. hygrophila, the age-stage, two-sex life table was used to understand the fitness and population parameters of individually-reared and group-reared A. hygrophila under elevated CO.sub.2 concentration. In individually-reared population, the development time of preadults, adult pre-oviposition period, and total pre-oviposition period of A. hygrophila in the elevated CO.sub.2 (eCO.sub.2, 750 ppm) treatment were shorter than those in the ambient CO.sub.2 (aCO.sub.2, 420 ppm) treatment. In group-reared population, the developmental time of preadults, female adult longevity, female proportion, adult pre-oviposition period, and total pre-oviposition period of A. hygrophila in eCO.sub.2 were longer than those in aCO.sub.2. Additionally, in both individually-reared and group-reared population, fecundity and oviposition days of A. hygrophila in eCO.sub.2 were higher than those in aCO.sub.2, and a higher intrinsic rate of increase, finite rate of increase, and the net reproductive rate of A. hygrophila were observed at eCO.sub.2. Moreover, shorter preadult development time, adult pre-oviposition period, total pre-oviposition period, male adult longevity, and higher fecundity were found in group-reared cohort at both aCO.sub.2 and eCO.sub.2. The results indicates that elevated CO.sub.2 has effects on the growth and reproduction of A. hygrophila, and the population growth rate of group-reared was faster and produced more offspring. Key words Agasicles hygrophila, ambient CO.sub.2, elevated CO.sub.2, individually-reared, group-reared
In taxonomy, qualitative methods are commonly used to analyze morphological characters, which can lead to dramatic changes in higher taxa. Geometric morphometrics (GM) has proven to be useful for ...discriminating species in various taxonomy groups. However, the application of geometric morphometrics in supraspecies classification is relatively scarce. In this study, we tested the controversial two subgenera classification of Chaetocnema with geometric morphometrics; a total of 203 Chaetocnema species representing 50% of all known species from around the world were selected for the analysis. We analyzed the shape of the pronotum, elytron, head, aedeagus, and spermatheca. The results showed that the two traditional subgenera distinctly differed from each other; therefore, we propose using two subgenera arrangements to facilitate the understanding and taxonomy of the Chaetocnema species (especially in the Oriental, Palearctic, and Nearctic regions). Additionally, the morphological diversity of the abovementioned structures of Chaetocnema was analyzed, and it was found that the highest morphological diversity was in the spermatheca, which was greater than that in the aedeagus. Our research demonstrated that GM could be useful for detecting morphological delimitation of the supraspecies taxa. It also showed that GM methods are applicable to insects as small as 2 mm in body size.
Fumigation with methyl bromide has been a long established and effective method for controlling many pests of stored products, including the key major pests that infest dry-cured hams, aged cheese, ...and other value-added durable stored products. Methyl bromide had been widely used for the disinfestation of dry-cured ham facilities in the United States, but is now phased out of use since it is an ozone-depleting substance. This paper reports laboratory studies to evaluate the efficacies of methyl bromide and phosphine for controlling two of the key arthropod pests of dry-cured hams and aged cheeses. Larvae of the red-legged ham beetle, Necrobia rufipes (Fabricius), were the most tolerant life stages when treated with either phosphine or methyl bromide for 48 h exposure at 23degreesC, whereas eggs of the mold mite, Tyrophagus putrescentiae (Schrank), were slightly more tolerant than mobile stages for both compounds. Under laboratory conditions, complete control was achieved for the both species with concentrations of 0.85 and 4.0 g/m.sup.3 of phosphine and methyl bromide, respectively, at 48 h exposure. The results give new information for judicious use of the existing stocks of methyl bromide, whether for pest mitigation or to help in developing a quarantine treatment schedule with that gas. Phosphine shows good potential as an effective alternative to methyl bromide, but if it was to be adopted as a fumigant in the dry-cured ham industry, methods to prevent metal corrosion would need to be designed and effectively implemented. Key words: lethal concentration, hydrogen phosphide, ham beetle, ham mite, country ham
The cervicornis species group of Taumacera Thunberg, 1814, endemic to Sri Lanka, is revised. Seven species, including three species new to science, are recognized: Taumacera cervicornis (Baly, 1861), ...T. lewisi (Jacoby, 1887), T. mirabilis (Jacoby, 1887), T. unicolor (Jacoby, 1887), T. adamskii sp. nov., T. maskeliya sp. nov., and T. sigiriya sp. nov. The representatives of this group are characterized by pectinate antennomeres and by 12-segmented antennae. Antennomeres XI and XII are firmly fused in most species, separated by a distinct suture; however, in T. cervicornis, antennomere XII appears to be moveable. Color photographs of habitus, body details, and aedeagi as well as female genitalia are presented.
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