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Despite their importance as potential biological control agents, species of the campoplegine genus Campoplex Gravenhorst, 1829 are hard to identify. Previous works provided short descriptions or poor illustrations of crucial characters, meaning it is often impossible to distinguish closely related species. We provide illustrations to identify species of the Campoplex difformis group and redescriptions of and illustrations for C. difformis (Gmelin, 1790), C. capitator Aubert, 1960, C. dubitator Horstmann, 1985, C. formosanae Horstmann, 2012, and C. unicingulatus (Schmiedeknecht, 1909). In addition, the taxonomic status of C. difformis is clarified; a lectotype is designated for C. capitator in Aubert’s collection in Lausanne and the host record for this species on Ancylis mitterbacheriana (Denis & Schiffermüller, 1775) is queried; Campoplex corsicator Aubert, 1960 stat. nov. is removed from synonymy with Campoplex tibialis (Szépligeti, 1916) and redescribed.
The genus Cotesia Cameron, 1891 is one of the most diverse of the Microgastrinae, a subfamily of wasps that are exclusively endoparasitic on lepidopteran larvae. Species of Cotesia are widely utilised as biological control agents across the world. In Australia, there are currently 10 confirmed native species as well as four species introduced for the management of lepidopteran pests. The genus is morphologically conserved and has not been studied in the Australasian region for many decades. In this study, we use both comparative morphology and sequence data from the COI gene to delineate species, and in so doing describe seven new species from Australia: C. lasallei sp. nov., C. medusae sp. nov., C. ocellata sp. nov., C. reidarum sp. nov., C. scripta sp. nov., C. tjapekki sp. nov. and C. wonboynensis sp. nov., raising the number of species of Cotesia formally recorded in Australia to 21. We also provide updated descriptions of the previously described native species, diagnoses for the introduced species and a key to all currently described species found on the continent and from Papua New Guinea. This study treats only a fraction of the likely diversity of Cotesia, but provides a solid framework for future work.
Die Larvalparasitoide Venturia canescens (Gravenhorst) und Habrobracon hebetor (Say) sind Parasitoide der Mehlmotte Ephestia kuehniella, der Dörrobstmotte Plodia interpunctella und der Tropischen Speichermotte E. cautella. H. hebetor ist ein idiobionter, gregärer Ektoparasitoid, d.h. die Wirtslarve wird vor der Eiablage paralysiert und mehrere Nachkommen entwickeln sich an einem Wirtstier (Hase, 1922). V. canescens ist ein koinobionter, solitärer Endoparasitoid, d.h. die Wirtslarve wird vor der Eiablage nicht paralysiert und nur ein Nachkomme entwickelt sich in einem Wirtstier, welches erst kurz vor der Verpuppung eingeht (1937). Press & al. (1977) zeigten in Versuchen in kleinen Versuchsgefäßen, dass V. canescens vollständig von H. hebetor unterdrückt wurde. Da bereits von V. parasitierte Larven von H.paralysiert und anschließend parasitiert wurden, konnte sich der Nachwuchs von V.nicht entwickeln. V.ihrerseits war nicht in der Lage, bereits von H.paralysierte Larven zu parasitieren. Press & al. (1977) schlussfolgerten daraus, dass V. canescens bei einer massenweisen Freilassung von H. hebetor zur biologischen Bekämpfung unter Praxisbedingungen verdrängt werden würde. Dennoch treten beide Parasitoide in Mühlen, Bäckereien und Lagerhäusern in Mitteleuropa auch bei einem Einsatz von H. hebetor zur biologischen Bekämpfung gemeinsam auf (Prozell & Schoeller, 1998; Lukas, 2002, Prozell & unveröffentl. Daten). Eine mögliche Erklärung könnte die bessere Wirtsfindungsfähigkeit von V. canescens in größeren Räumen sein. Das Wirtsfindungsvermögen beider Arten wurde bereits in einigen Arbeiten behandelt (Parra & Al., 1996; Desouhant & 2005), jedoch wurden die Auswirkungen auf die Konkurrenz dabei nicht betrachtet. Das Ziel dieser Arbeit war es daher, die räumliche Konkurrenz zwischen H. hebetor und V. canescens in Räumen mit zunehmendem Volumen zu untersuchen.
Arcola malloi (Pastrana, 1961) is a junior subjective synonym of Macrorrhinia endonephele (Hampson, 1918) syn. nov. (Lepidoptera: Pyralidae). The species is a biological control agent introduced in United States and Australia to control alligatorweed, Alternanthera philoxeroides (Mart.) Griseb. (Amaranthaceae). The synonymy is recognized by comparison of type specimens, genitalic dissections, and DNA COI barcoding. Vogtia Pastrana, 1961 syn. nov. and Arcola Shaffer, 1995 syn. nov. are synonymized with Macrorrhinia Ragonot, 1887. Macror-rhinia megajuxta (Neunzig and Goodson, 1992) comb. nov. is transferred from Ocala Hulst, 1892. Lectotypes are designated for Divitiaca ochrella Barnes and McDunnough, 1913, and Divitiaca simulella Barnes and Mc-Dunnough, 1913.
Alien plants were first recorded in 1937 in the 2 million ha Kruger National Park (KNP, a savanna protected area in South Africa), and attempts to control them began in the mid-1950s. The invasive alien plant control program expanded substantially in the late 1990s, but its overall efficacy has not been determined. We present an assessment of invasive alien plant control operations over several decades in KNP. We based our assessment on available information from a range of control programs funded from various sources, including national public works programs, KNP operational funds, and foreign donor funds. Over ZAR 350 million (~ US$ 27 million) has been spent on control interventions between 1997 and 2016. We found evidence of good progress with the control of several species, notably Opuntia stricta, Sesbania punicea, Lantana camara and several aquatic weeds, often because of effective biological control. On the other hand, we found that over one third (40%) of the funding was spent on species that have subsequently been recognised as being of lower priority, most of which were alien annual weeds. The allocation of funds to non-priority species was sometimes driven by the need to meet additional objectives (such as employment creation), or by perceptions about relative impact in the absence of documented evidence. We also found that management goals were limited to inputs (funds disbursed, employment created, and area treated) rather than to ecological outcomes, and progress was consequently not adequately monitored. At a species level, four out of 36 species were considered to be under complete control, and a further five were under substantial control. Attempts to control five annual species were all considered to be ineffective. On the basis of our findings, we recommend that more studies be done to determine impacts associated with individual invasive alien species; that the criteria used to prioritise invasive alien species be documented based on such assessments, so that management can justify a focus on priority species; and that funding be re-directed to those species that clearly pose greater threats, and for which other solutions (such as biological control) are not an option.
Ambrosia artemisiifolia (common ragweed) is an invasive species native to North America and was accidentally introduced to Europe in the 19th century. Widespread in disturbed habitats, it is a major weed in spring-sown crops and it causes serious allergic rhinitis and asthma due to its allergenic pollen. The aim of this research was to analyse the effects of both competitive vegetation and herbivory by Ophraella communa to control A. artemisiifolia in an agricultural area of north-western Italy. Hayseed mixtures, both over-seeded over the resident plant community or after ploughing, when seeded before the winter season, were able to suppress the establishment of A. artemisiifolia as well as to reduce its growth in terms of plant height and inflorescence size. Defoliation of A. artemisiifolia by O. communa at the end of the growing season was conspicuous but most of the plants still produced flowers and seeds. However, significant O. communa attack was recorded for reproductive structures. As for non-target species, O. communa was mainly recorded on Asteraceae, with low density and low degree of damage. Reduction of inflorescence size due to competitive vegetation and damage to male flowers by O. communa may diminish the amount of available pollen. The results of this study may be useful for the implementation of management measures to control A. artemisiifolia in agricultural areas using mixtures of native species.