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The larvicidal activity of crude petroleum ether, toluene, n-butanol, ethyl acetate, acetone, and methanol extracts of the seeds of Clausena lansium was assayed for their toxicities against the early fourth instar larvae of Aedes albopictus. The larval mortality was observed after 24-h exposure. The LC(50) value of petroleum ether extract was 22.99 ppm, showing the best larvicidal activity among all six solvent extracts. A cinnamon amide compound lansiumamide B (N-methyl-N-cis-styrylcinnamamide) was isolated from the petroleum ether extract by column chromatographic method, which exhibited a strong larvicidal activity against the early fourth instar larvae of A. albopictus with LC(50) and LC(90) values of 0.45 and 2.19 ppm, respectively. The structure was elucidated by (1)H NMR, (13)C NMR spectral data. The larvicidal activity against mosquito of lansiumamide B from the seed of C. lansium was evaluated for the first time.

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The wasp Spalangia endius Walker (Hymenoptera: Pteromalidae) is a major parasitoid of the pupae of fruit flies, which are a common agricultural pest. An understanding of this intricate host–parasitoid interaction could provide basic information necessary for the sustainable integrated biological control of fruit flies. In this study, we investigated the effect of S. endius on different-aged pupae of the melon fly Bactrocera cucurbitae Coquillett by using choice and nonchoice tests under laboratory conditions. We showed that S. endius females oviposited, and their progeny successfully developed, in different-aged pupae of B. cucurbitae regardless of the method of exposure. There was an oviposition preference for 3–5-d-old pupa. The highest mean percentage parasitism occurred on 4- and 5-d-old hosts, followed by 2- and 3-d-old hosts. The average development time for both males and females was significantly longer in 6–7-d-old hosts than in the younger host stages. Adult females that developed from younger host pupae (2–5-d old) were significantly heavier than those from older host pupae (6–7-d old), and they also lived longer. The sex ratio (proportion of females) of the parasite progeny decreased with an increase in host age. Host mortality also decreased gradually as the pupal age increased. The differences in development time, body weight, and longevity between females and males were significant. These results suggest that S. endius is a good candidate for the biological control of B. cucurbitae.

The morphology and distribution of the antennal sensilla of Megalurothrips usitatus Bagnall and Thrips palmi Karny were examined using scanning electron microscopy (SEM). These are serious pests of various economically important crops, and their antennae are important in chemical communication. The antennae of both species consist of a scape, pedicel, and flagellum, but the flagellum of M. usitatus is made up of six sub-segments, whereas that of T. palmi consists of five sub-segments. Seven morphological sensilla types, including Böhm bristle (BB), sensilla campaniformia (Sca), three types of sensilla basiconica (Sb1, Sb2 and Sb3), two types of sensilla chaetica (Sch1 and Sch2), sensilla styloconica (Sst), sensilla trichodea (St), and sensilla cavity (Scav), were recorded in both species. The scape and pedicels exhibited Sch1, BB and Sca. The flagellum exhibited two types of Sch, three types of Sb, St, Sst and Scav. Based on these results, the putative function of the sensilla of M. usitatus and T. palmi are also discussed.