Ambrosia artemisiifolia is a well-known invasive species in Europe, causing health issues with its extremely allergenic pollen and yield loss through competition in agriculture. One potential biological control agent is Ophraella communa, accidentally introduced in Europe in 2013. This species was discovered in France in 2023, but before planning further mass releases for biological control, it is necessary to assess its safety for agricultural crops and local plant biodiversity. Prior to its first detection in France, we conducted a host-range study of the beetle in a confined laboratory with no-choice and choice tests for 16 plant species, selected based on the centrifugal phylogenetic method. Results showed a restricted host range to the Heliantheae tribe and minimal risk to indigenous European plant species, with no larval survival and barely any eggs laid on these plants. Choice tests also showed a strong preference of O. communa for A. artemisiifolia. Our results combined with previous studies and observations in the field in other countries suggest a low risk to sunflower, Helianthus annuus, which is an important crop in France. This confirms that O. communa could be a low-risk biological control agent that can be used in classical biological control programs against A. artemisiifolia in France.

Dung beetles are important ecosystem engineers, as they utilize the excrement produced by animals. For nearly 60 years, several species of dung beetle have been introduced to Australia to help mitigate the problems caused by the accumulation of livestock dung. The twenty-three successfully established species directly contribute to reducing the environmental impacts from dung accumulation, providing improvements to soil health, pasture productivity and pest fly reduction. Despite this success, there are still geographical and seasonal gaps in dung beetle activity, causing dung to remain on the soil surface. The continued importation of new dung beetle species is warranted to fill these gaps. One of the significant remaining gaps is during spring in southern Australia. Four spring-active dung species from Morocco were selected for a new importation program (2018–2022): Euonthophagus crocatus, Onthophagus vacca, Onthophagus marginalis subsp. andalusicus and Gymnopleurus sturmi. These species were surveyed at four sites in Morocco on an altitudinal gradient to assess their seasonal activity. The four species were found at all sites during spring, but in varying abundances, with different species dominating different sites. This is most likely due to differences in local conditions such as soil type. Seasonal activity varied depending on elevation. Gymnopleurus sturmi was found to be active later in the season and should be considered as a summer species. The four species selected will be, if they establish, a useful addition to the already introduced and established dung beetle fauna in Australia.

Dung beetles are important ecosystem engineers as they play an important role in recycling faces from animals. Dung beetles have evolved different behaviors, including dung ball rolling for their egg and developing offspring. Ball rolling is a complex behavior that varies between species. In some species, males roll the dung ball and females choose partners based on this, while in other species, males and females work together to form the ball. Competition can be fierce with fighting, and ball stealing is common. Gymnopleurus sturmi is a ball rolling species that exhibits gregarious behavior with adults congregating on a dung source. This study assesses sex‐related roles in ball rolling as well as the impact of varying sex ratios on the number of balls produced, either left at the surface or buried and fertilized, and emergence rates of the offspring. The theoretical number of offspring per female was used as a measure of fitness. Results show that both males and females can produce dung balls, and higher numbers were obtained when males and females were separated. Female‐biased sex ratio produced mostly buried and fertilized balls, while male‐biased sex ratio produced more unburied balls left on the surface. When females were alone, they produced the maximum number of total dung balls compared to the rest of the treatments. On the other hand, emergence rate was found to be higher when more males were present. When females were alone, emergence rate was extremely low, suggesting reduced sperm storage. Using the theoretical number of offspring per female, no difference in fitness was observed when males and females were both present. In a gregarious species like G. sturmi, finding a partner would be easier than for other dung beetle species, which could explain an increasing competition between males and reducing the need to store sperm for the longer term. This study highlights the diversity of behaviors present in this species.

Passiflora foetida senso lato L. (Passifloraceae), native to the Americas, is an invasive vine impacting areas of environmental, economic, cultural and social importance across northern Australia. The leaf‐sucking mirid, Engytatus passionarius Minghetti, Maestro and Dellapé (Hemiptera: Miridae), was recently described and identified as a potential biological control agent of P. foetida following native range surveys in northwestern Argentina. Its biology and host range were investigated in Argentina and under quarantine in Australia to assess its suitability for release. Host specificity was initially evaluated in the native range through field host range observations, laboratory studies assessing zoophagy and no‐choice tests on available Passiflora species. These studies indicated a high level of specificity to P. foetida , supporting further evaluation in Australian quarantine. Comprehensive no‐choice host specificity testing included 31 plant species selected based on their phylogenetic relationships to the target weed spanning the Passifloraceae, Salicaceae, Achariaceae, Violaceae, Euphorbiaceae and Phyllanthaceae. Feeding, oviposition and successful development to adulthood occurred consistently on P. foetida . Survival rates were significantly higher on the target weed than on nontarget plant species, where individuals experienced markedly increased mortality. Feeding on nontarget plants was generally low and exploratory, whereas consistent vegetative damage occurred on P. foetida . Developmental success for the mirid was also substantially reduced on nontargets (mean 0.2–4.6 F1 adults) compared with P. foetida (mean 52.5 F1 adults). Six nontarget Passiflora species were further evaluated in choice tests. E. passionarius consistently preferred P. foetida , initiating feeding more rapidly and producing higher nymph densities than on nontarget species. Completion of the life cycle occurred only on P. foetida . Overall, results from native‐range studies, quarantine experiments and field observations demonstrate that E. passionarius is highly host‐specific to P. foetida and represents a promising candidate for biological control in Australia.