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Ambrosia beetles from the tribe Xyleborini are part of nearly all forest ecosystems. Because of their small size, haplodiploid mating structure, and protected lives inside the sapwood of woody plants, they have a unique ability to expand into new regions via inadvertent human transport. A small number of invasive xyleborines cause significant damage to forests, lumber concerns, and agricultural systems. Most ambrosia pests damage or kill trees by the accumulation of beetle attacks, one is known to cause tree death through the introduction of pathogenic fungus into susceptible Lauraceae trees. The relationships between ambrosia fungi and their beetle vectors range from mutualistic symbiosis to facultative association, but most remain unstudied. Unresolved taxonomies, convergent morphologies, and the difficulty of sampling ambrosia fungi over their entire global ranges make comprehensive surveys of ambrosia fungi difficult to achieve. Ambrosia fungi from Europe and North America are moderately well documented, however, we have yet to sufficiently document those from Africa, Asia, Australia, and South America. Worldwide cooperation to improve and standardize scientific study of the ambrosia symbioses is needed to better understand these impactful organisms.

Sesiids are a diverse group of predominantly diurnal moths, many of which are Batesian mimics of Hymenoptera. However, their diversity and relationships are poorly understood. A multi-gene phylogenetic analysis of 48 North American sesiid species confirmed the traditional taxonomic tribal ranks, demonstrated the paraphyly of Carmenta and Synanthedon with respect to several other genera and ultimately provided minimal phylogenetic resolution within and between North American and European groups. Character support from each gene suggested inconsistency between the phylogenetic signal of the CAD gene and that of the other four genes. However, removal of CAD from subsequent phylogenetic analyses did not substantially change the initial phylogenetic results or return Carmenta and Synanthedon as reciprocally monophyletic, suggesting that it was not impacting the overall phylogenetic signal. The lack of resolution using genes that are typically informative at the species level for other lepidopterans suggests a surprisingly rapid radiation of species in Carmenta/Synanthedon. This group also exhibits a wide range of mimicry strategies and hostplant usage, which could be fertile ground for future study.

Plant-associated arthropods have been shown to cross large oceanic distances on floating plant material and to establish themselves on distant landmasses. Xyleborini (Coleoptera: Curculionidae: Scolytinae) ambrosia beetles occur in forests worldwide and are likely capable of long range dispersal. In less than 20 million years, this group dispersed from Asia to tropical regions of Africa and South America. The phylogeny, taxonomy, and biogeography of one Xyleborus species group which occurs on both continents are reviewed for this study. Based on a well-resolved molecular phylogeny resulting from parsimony, likelihood, and Bayesian analyses of four gene loci, we describe a new monophyletic genus, Xenoxylebora Osborn, Smith & Cognato, gen. nov., for this bicontinental Xyleborus species group with seven Afrotropical and six Neotropical species. Six new species are described: Xenoxylebora pilosa Osborn, Smith & Cognato, sp. nov. from Africa, and Xenoxylebora addenda Osborn, Smith & Cognato, sp. nov., Xenoxylebora calculosa Osborn, Smith & Cognato, sp. nov., Xenoxylebora hystricosa Osborn, Smith & Cognato, sp. nov., Xenoxylebora serrata Osborn, Smith & Cognato, sp. nov., and Xenoxylebora sulcata Osborn, Smith & Cognato, sp. nov., from South America. Seven new combinations from Xyleborus are proposed: Xenoxylebora caudata (Schedl 1957) comb. nov., Xenoxylebora collarti (Eggers 1932) comb. nov., Xenoxylebora perdiligens (Schedl 1937) comb. nov., Xenoxylebora sphenos (Sampson 1912) comb. nov., Xenoxylebora subcrenulata (Eggers 1932) comb. nov., and Xenoxylebora syzygii (Nunberg 1959) comb. nov. from Africa, and Xenoxylebora neosphenos (Schedl 1976) comb. nov. from South America. One new synonym is proposed: Xenoxylebora sphenos (Sampson 1912) = Xyleborus tenellusSchedl 1957 syn. nov. Descriptions, diagnoses, images, and a key to the identification of all 13 species are provided. The sequence of colonization between Africa and South America is uncertain for Xenoxylebora. Prevailing ocean currents and predominant locality patterns observed for other organisms suggest an African Xenoxylebora origin. However, the phylogeny, biogeographical analyses, and a calibrated divergence time suggest a possible South American origin for African Xenoxylebora (2.3 Ma, 95% HDP 4.5–0.6 Ma), which is supported by the occurrence of ocean counter currents between the continents and evidence of dispersal from South America to Africa among some plant and arthropod taxa.

Ambrosia beetles from the scolytine tribe Xyleborini (Curculionidae) are important to the decomposition of woody plant material on every continent except Antarctica. These insects farm fungi on the walls of tunnels they build inside recently dead trees and rely on the fungi for nutrition during all stages of their lives. Such ambrosia fungi rely on the beetles to provide appropriate substrates and environmental conditions for growth. A small minority of xyleborine ambrosia beetle-fungal partnerships cause significant damage to healthy trees. The xyleborine beetle

BACKGROUND: The potential for enhanced degradation of the carbamoyloxime nematicides aldicarb and oxamyl and the organophosphate fosthiazate was investigated in 35 UK agricultural soils. Under laboratory conditions, soil samples received three successive applications of nematicide at 25 day intervals. RESULTS: The second and third applications of aldicarb were degraded at a faster rate than the first application in six of the 15 aldicarb-treated soils, and a further three soils demonstrated rapid degradation of all three applications. High organic matter content and low pH had an inhibitory effect on the rate of aldicarb degradation. Rapid degradation was observed in nine out of the ten soils treated with oxamyl. In contrast, none of the fosthiazate-treated soils demonstrated enhanced degradation. CONCLUSION: The potential for enhanced degradation of aldicarb and oxamyl was demonstrated in nine out of 15 and nine out of ten soils respectively that had previously been treated with these active substances. Degradation of fosthiazate occurred at a much slower rate, with no evidence of enhanced degradation. Fosthiazate may provide a useful alternative in cases where the efficacy of aldicarb and oxamyl has been reduced as a result of enhanced degradation. Copyright © 2009 Society of Chemical Industry

The potential for enhanced degradation of the carbamoyloxime nematicides aldicarb and oxamyl and the organophosphate fosthiazate was investigated in 35 UK agricultural soils. Under laboratory conditions, soil samples received three successive applications of nematicide at 25 day intervals.The second and third applications of aldicarb were degraded at a faster rate than the first application in six of the 15 aldicarb-treated soils, and a further three soils demonstrated rapid degradation of all three applications. High organic matter content and low pH had an inhibitory effect on the rate of aldicarb degradation. Rapid degradation was observed in nine out of the ten soils treated with oxamyl. In contrast, none of the fosthiazate-treated soils demonstrated enhanced degradation.The potential for enhanced degradation of aldicarb and oxamyl was demonstrated in nine out of 15 and nine out of ten soils respectively that had previously been treated with these active substances. Degradation of fosthiazate occurred at a much slower rate, with no evidence of enhanced degradation. Fosthiazate may provide a useful alternative in cases where the efficacy of aldicarb and oxamyl has been reduced as a result of enhanced degradation.