Adults and larvae of Askalaphium depressum (Bates) live in association with hispine chrysomelid beetles of the genus Cephaloleia Chevrolat, in the appressed leaf axils of the riverside reed, Gynerium sagittatum (Aubl.) P. Beauv. This reed is locally known in Amazonian Perú as Caña Brava. Both adult and larval A. depressum eat larvae of Cephaloleia species and larvae of an unidentified dipteran, and perhaps other insects living in the confines of the leaf sheaths of that plant species. The geographic range of Caña Brava reed extends from subtropical South America northward to México (and Florida), but A. depressum has been found thus far at only three Amazonian localities, probably indicating its cryptic microhabitat and lack of collecting, therein. Likely, the range of this commensal carabid species is more extensive and may approach the range of its host plant and hispine food. Structural features of second and third instar larvae of A. depressum are described for the first time. Larval character states that are shared with a related ctenodactyline, Leptotrachelus dorsalis (Fabricius), provide a basis for characterization of the tribe Ctenodactylini.

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The establishment of new symbiotic interactions between introduced species may facilitate invasion success. For instance, tawny crazy ant (Nylanderia fulva Mayr) is known to be an opportunistic tender of honeydew producing insects and this ants’ symbiotic interactions have exacerbated agricultural damage in some invaded regions of the world. The invasive sorghum aphid (Melanaphis sorghi Theobald) was first reported as a pest in the continental United States–in Texas and Louisiana–as recent as 2013, and tawny crazy ant (TCA) was reported in Texas in the early 2000s. Although these introductions are relatively recent, TCA workers tend sorghum aphids in field and greenhouse settings. This study quantified the tending duration of TCA workers to sorghum aphids and the impact of TCA tending on aphid biomass. For this study aphids were collected from three different host plant species (i.e., sugarcane, Johnson grass, and sorghum) and clone colonies were established. Sorghum is the main economic crop in which these aphids occur, hence we focused our study on the potential impacts of interactions on sorghum. Quantification of invasive ant-aphid interactions, on either stems or leaves of sorghum plants, were conducted in greenhouse conditions. Our results show that although these two invasive insect species do not have a long coevolutionary history, TCA developed a tending interaction with sorghum aphid, and aphids were observed excreting honeydew after being antennated by TCA workers. Interestingly, this relatively recent symbiotic interaction significantly increased overall aphid biomass for aphids that were positioned on stems and collected from Johnson grass. It is recommended to continue monitoring the interaction between TCA and sorghum aphid in field conditions due to its potential to increase aphid populations and sorghum plant damage.

Gene drive is a new form of biotechnology designed to bias the inheritance of selected traits in animal or plant species that reproduce sexually and have relatively short reproductive cycles. Unlike traditional breeding techniques and other forms of biotechnology, gene drive is designed to spread in wild populations. As such, the prospect of its application raises ecological and socioeconomic concerns that the current system of biotechnology regulation in the USA is ill-equipped to address. Foremost among the proposals for reform is the need for deliberative participation in decision-making by stakeholders representing a broader range of interests and analytical perspectives. As appealing as they are in the abstract, these recommendations overlook both practical and political challenges to democratic governance in administration that have received little attention.

Aphids adopt many defensive strategies against natural enemies. While immediate strategies like emitting alarm pheromones or producing secretions are often researched, fewer studies have assessed long‐term defences that include physiological adaptive responses affecting aphid reproduction. Fecundity compensation is a post‐wounding increase in host reproduction, which benefits the offspring of wounded or parasitized insects. Though fecundity compensation can be expressed by individuals experiencing natural enemy attacks, it can also be transgenerational, wherein the offspring of wounded or parasitized mothers reproduce more than the offspring of unaffected mothers. The possibility of fecundity compensation was tested on laboratory populations of the sorghum aphid (SA), Melanaphis sorghi (Hemiptera: Aphididae), in response to wounding from a needle puncture or sting by Aphelinus nigritus Howard (Hymenoptera: Aphelinidae). No evidence of reproductive compensation was found among needle‐wounded, stung and mummified (successfully parasitized), or stung but not mummified SAs in the parental generation, nor in the F1 generation of needle‐wounded or stung but not mummified aphids. However, transgenerational fecundity compensation was observed in F1 daughters of mummified F0 mothers, though this effect did not occur in the F2 generation. At the molecular level, changes were not detected in the expression of DNA methylation and histone modification genes that potentially mediated transgenerational fecundity compensation in SAs stung by A. nigritus, regardless of whether aphids were successfully parasitized. As SA is a cereal aphid pest, the possibility of fecundity compensation should be tested when assessing the suitability of certain parasitoids as biological control agents.