Discovery of false coconut scale (Aspidiotus rigidus) and three of its primary parasitoids in Việt Nam,and likely species origins

The false coconut scale, Aspidiotus rigidus Reyne (Hemiptera: Diaspididae), is a serious pest of coconut in the Indonesian and Philippine archipelagos. Field surveys in Viêt Nam in 2015–2018 discovered A. rigidus (a new country record). Also found were three of its primary hymenopteran parasitoids: an unidentified ectoparasitic Aphytis species (Aphelinidae) and two endoparasitoids, Comperiella calauanica (Encyrtidae) and Pteroptrix parvipennis (Aphelinidae). Aphytis sp. was the commonest parasitoid; the average level of parasitism of A. rigidus found in six surveys was 46%, in immatures of both sexes and adult females. Comperiella calauanica was recorded in three surveys, with an average parasitism level of 54% in adult female A. rigidus. It was also found attacking Aspidiotus destructor Signoret. Pteroptrix parvipennis was recorded in 47% of second instar A. rigidus in one survey. In molecular phylogenies based on 28S and COI genes, Pteroptrix parvipennis grouped with species of Encarsia. Although A. rigidus occurs in the largest coconut-growing areas in Việt Nam, incidence of the scale is low, and no outbreaks have been recorded. Its parasitoids therefore have potential for use as biological control agents in areas where the scale is problematic. The low incidence of A. rigidus in Việt Nam and the presence of the three parasitoid species there suggests that the scale and these parasitoids originated in Indochina.     

Seasonal surveillance of deer and horse flies (Diptera: Tabanidae), Gyeonggi province,Republic of Korea

Deer and horse flies, Family Tabanidae, are biological, mechanical, and potential vectors of approximately 27 viral, bacterial, and helminthic pathogens of veterinary and medical importance. Biting fly surveillance was conducted using New Jersey light traps and Mosquito Magnet® traps from May-October during 2015–2018 at eight sites (villages and US military installations and training areas) near/in the Demilitarized Zone and at a US military installation in southern Gyeonggi province, Republic of Korea.A total of 9985 deer and horse flies, comprising 4 genera and 17 species, were collected. The predominant species collected was Chrysops mlokosiewiczi (95.39%), followed by Chrysops suavis (1.48%) and Haematopota koryoensis (1.07%), while the remaining species accounted for only 2.06% of the specimens collected. A bimodal peak was observed for C. mlokosiewiczi in June and late-July, but not for the other two predominant species during the whole of the study period. This study provides and insight into ecological behavior and seasonal abundance of deer and horse flies in Gyeonggi province, Republic of Korea.     

Behavioral response of Nilaparvata lugens (Stål), Cyrtorhinus lividipennis Reuter and Paederus fuscipes Curtis to three synthetic volatile chemical compounds

Plant essential oils (EOs) and a wide range of chemicals affect insect pests in many ways, such as via stimulatory, deterrent, toxic and hormonal effects. Three different compounds ((E)-β-caryophyllene (E-β-C), D-limonene (D-lime) and trans-2-dodecenol (T-2-D)) were tested against Nilaparvata lugens, Cyrtorhinus lividipennis and Paederus fuscipes, and their behavioral response was assessed. The results showed that on average, more N. lugens nymphs were repelled by E-β-C and T-2-D than by D-lime. More C. lividipennis nymphs were attracted to T-2-D and D-lime than to E-β-C. However, P. fuscipes displayed no significant response to the three chemical compounds. The results also demonstrated that T-2-D has exerted significant repellency against N. lugens and a significant attraction for C. lividipennis, while E-β-C and D-lime have no significant effect on any tested insect. T-2-D was selected and tested in a greenhouse under semi-field conditions, where the observations confirmed the results of the laboratory experiments. From the results, it can be concluded that T-2-D at a concentration of 0.06 g/L is an effective synthetic volatile chemical compound and is the strongest repellent of N. lugens and the strongest attractant for C. lividipennis. This synthetic chemical compound can be used as a pest management tool in rice agroecosystems.     

Year-round trap capture of the spotted-wing drosophila,Drosophila suzukii (Diptera: Drosophilidae), in Korean strawberry greenhouses

Korean greenhouse strawberries are mostly cultivated from October to May, which includes the cold winter season. During this time, the population size of the spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is expected to decrease in the wild, and is also expected to decrease inside the greenhouses, as long as SWD are not already present inside. Field surveys of SWD have been extensively carried out for field-grown agricultural fruits, but no study has been conducted for greenhouse fruits, such as strawberries. In this study, SWD capture patterns were examined inside and outside of the greenhouse blocks, and in the nearby woodlands in a southwestern locality of Korea using selected traps and attractants for nearly 19 months—in addition to several greenhouse blocks—during the strawberry cultivating periods. The highest capture period was observed from October to mid-December in woodlands, whereas capture number subsequently and sharply decreased up to mid-April, resulting in mostly zero-captures or low captures (≤10). During this period, a zero-capture period was observed inside the greenhouse that lasted for nearly three months (late December to late February). An incubation of the fallen strawberries supported the results of trap capture from inside the greenhouses. Taken together, the occurrence of SWD in the strawberry greenhouses is likely to be highly dependent on that of the nearby woodlands. Thus, a sharp winter drop and the subsequent zero- or low-capture periods in the woodland areas were likely responsible for the observed zero-capture periods inside the greenhouses.     

Protaitzehoia Yang三叶虫分类位置的再研究-答“也论Protaitzehoia Yang三叶虫的分类位置”．．．

文章从三叶虫的头尾搭配问题的讨论对"也论Protaitzehoia Yang三叶虫的分类位置"一文中置于原太子河虫属的某些尾部的可靠性提出了质疑,认为插图2中的尾(K),由于缺少宽而下凹的尾边缘,应属于Stephanocare Monke,1903一属的尾部;插图2中的尾(L)的归属尚难定论.将原太子河虫属的头盖、活动颊、尾部、唇瓣与Cheilocephalus Berkey,1898属的头盖、活动颊、尾部、唇瓣对比后,认为原太子河虫属应归属Cheilocephalidae Shaw,1956.