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A new parasitoid reared from Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), Sclerodennus pupariae n. sp. (Hymenoptera: Bethylidae), is described from China. S. pupariae was reared from A. planipennis in China attacking velvet ash (Fraxinus velutina Tort.), a tree native to North America. Life-history studies of S. pupariae in the field and laboratory indicated it is a gregarious idiobiont ectoparasitoid of pupa and larva ofA. planipennis and has up to five generations per year. Parasitism rate in the field was 13%. Adult wasps reared from single host pupa or mature larva ranged from 24 to 56 individuals. Based on laboratory rearing, the emerging adult female to male ratio was 22:1. The new parasitoid species has a high potential as a biocontrol agent for emerald ash borer. Diagnosis of the new species with comparisons to Sclerodermus harmandi (Buysson) and a key to Sclerodermus known in China are provided. [ABSTRACT FROM AUTHOR]

The article presents information on a study related to basic ecology of a parasitoid species Spathius agrili (S. agrili) which is a predator of the emarald ash borer, Agrilus planipennis (A. planipennis). It further informs that A. planipennis is a pest of Fraximus velutina (F. velutina), velvet as plant in China, which has caused plantation damage after being accidentally introduced in North America. It also presents photographic images of the life stages and behavior of S. agrili.

The success of classical biological control programs depends in part on understanding climate effects on introduced agents. Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae), a larval endoparasitoid of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is being introduced to EAB-invaded regions of the United States (USA) and Canada for biological control. To optimize regional release strategies and increase efficiency of the EAB-biocontrol program, we determined the effects of five constant temperatures from 15 °C to 35 °C on T. planipennisi parasitism rate, development, adult longevity, and fecundity in EAB. Results showed a decrease in parasitoid development time from 139.8 days at 15 °C to 26.3 days at 30 °C, while no parasitoid eggs hatched at 35 °C. Parasitism rates, provisioned with an excess of host larvae throughout their life, increased from 1.4% at 15 °C to 28% at 30 °C then declined to 0.5% at 35 °C. Adult parasitoid longevity declined from 24 weeks at 15 °C to <2 weeks at 35 °C. Fertility table analyses revealed T. planipennisi net reproductive rate was highest at 25 °C, and intrinsic and finite rates of increase were highest at 30 °C, suggesting 25–30 °C as optimal rearing temperatures for this parasitoid. Combining these results with temperature data from climate zones of 3–7 in the USA, we predicted T. planipennisi can complete more than one generation in all locations in these climatic zones, with more generations in warmer climates. Moreover, our findings also suggest that despite the availability of suitable EAB larval stages for parasitism, releases of T. planipennisi in early spring or late fall in cold climate zones may be suboptimal due to low temperatures, as may mid-summer releases in hot climate zones due to high temperatures. [ABSTRACT FROM AUTHOR]

In this study, we detect and track extratropical cyclones using 6-hourly mean sea level pressure data taken from the Twentieth Century Reanalysis version 3 (20CRv3) over the period 1951–2015 and compare them with those in the Interim and fifth generation of ECMWF reanalyses over the period 1979–2018. Three indices were employed to characterize cyclone activity, including cyclone count, cyclone intensity, and a cyclone activity index (CAI) that combines the count and intensity. The results show that the cyclone indices in the three datasets have comparable annual climatologies and seasonal evolution over the northern extratropical land and ocean in recent decades. Based on the cyclone indices over the period 1951–2010 in 80 ensemble members of 20CRv3, cyclone count and intensity are negatively correlated in winter and tend to be positively and weakly correlated in summer. The interannual CAI variability is dominated by the cyclone count variability. Regional mean cyclone activity can be well represented using the ensemble average cyclone index. We then examined the linkage of the cyclone activity in 20CRv3 and observed cold and warm extremes over Eurasia and North America over the period 1951–2010. In winter, the principal components of interannual cold and warm extreme anomalies are more correlated with the regional mean cyclone count index over Eurasia, while they are more correlated with the cyclone intensity index over North America. The temperature anomalies associated with the regional and ensemble mean cyclone count index explain about 10% (20%) of interannual cold (warm) extreme variances averaged over Eurasia. The temperature anomalies associated with the mean cyclone intensity explain about 10% of interannual cold and warm extreme variances over North America. Large-scale atmospheric circulation anomalies in association with cyclone activity and the induced temperature advection drive temperature anomalies over Eurasia and North America. In summer, circulation and thermal advection anomalies associated with cyclone activity are weak over the two continents. Hence, that season's relationship between cyclone activity and extreme temperature variability is weak. [ABSTRACT FROM AUTHOR]