An identification key based on French ladybird colouration is proposed for the tribes Chilocorini, Coccinellini, and Epilachnini. These tribes were chosen based on their relatively limited species diversity, as well as their large size and high colour diversity, making them easy to observe and collect. The identification key runs on Xper3 software, which allows the building of structured knowledge bases and online free-access keys. The online interactive Xper key is available at http://french-ladybird.identificationkey.fr.

Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids.

Background Tropical coral reefs cover ca. 0.1% of the Earth’s surface but host an outstanding biodiversity and provide important ecosystem services to millions of people living nearby. They are currently threatened by local stressors (e.g. nutrient enrichment and chemical pollution arising from poor land management, sewage effluents, agriculture, industry) and global stressors (mainly seawater warming and acidification, i.e. climate change). Global and local stressors interact in different ways, but the presence of one stressor often reduces the tolerance to additional stress. While global stressors cannot be mitigated solely by local actions, local stressors can be reduced through ecosystem management, therefore minimizing the impact of climate change on coral reefs. We systematically mapped the evidence of impacts of chemicals arising from anthropogenic activities on tropical reef-building corals, which are the main engineer species of reef ecosystems, to inform decision-makers on the available evidence on this topic. Methods We searched the relevant literature using English terms combined in a tested search string in two publication databases (Scopus and Web Of Science Core Collection). The search string combined terms describing the population (tropical reef-building corals) and the exposure (chemicals). We searched for additional literature through three search engines, three dissertations repositories, 11 specialist websites, and through a call to local stakeholders. Titles, abstracts, and full-texts were successively screened using pre-defined eligibility criteria. A database of all studies included in the map with coded metadata was produced. The evidence was described and knowledge clusters and gaps were identified through the distribution and frequency of studies into types of exposure and/or types of outcomes and/or types of study. Review findings The initial searches identified 23,403 articles which resulted in 15,177 articles after duplicate removal. Among them, 908 articles were retained after screening process, corresponding to 7937 studies (a study being the combination of a taxon, an exposure, and an outcome). Among these studies, 30.5% dealt with the impact of nutrient enrichment on corals while 25% concerned the impact of human activities without reference to a chemical. The most measured outcomes were those related to the chemical concentration in corals (bioaccumulation, 25.8%), to coral physiology (16.9%), cover (14%), and mortality (9%). Half of the studies (48.4%) were experimental—the exposure was controlled by the researchers—and were conducted in laboratory conditions (39.4%) and in situ (9%). The most studied taxa, exposure, and outcomes were different between experimental and observational studies. Conclusions We identified four well-represented subtopics that may be amenable to relevant full syntheses via systematic reviews: (1) evidence on bioaccumulation of chemicals by corals; (2) evidence on the effects of nutrient enrichment on corals; (3) evidence on the effects of human activities on corals; and (4) evidence on the ecotoxicological effects of chemicals on corals (except nutrient enrichment). The systematic map shows that corals in their natural environment can be exposed to many categories of chemicals, and that there is a complete gap in experimental research on the combined effects of more than two categories of chemicals. We therefore encourage research on this topic.

Background Tropical coral reefs cover only ca. 0.1% of the Earth’s surface but harbour exceptional marine biodiversity and provide vital ecosystem services to millions of people living nearby. They are currently threatened by global (e.g. climate change) and local (e.g. chemical pollution) stressors that interact in multiple ways. While global stressors cannot be mitigated by local actions alone, local stressors can be reduced through ecosystem management. Here, we aimed to systematically review experimental studies assessing the toxicity of chemical pollutants to tropical reef-building corals to generate accessible and usable knowledge and data that can be used to calculate measurement endpoints in ecological risk assessment. From the quantitative estimates of effects, we determined toxicity thresholds as the highest exposures tested at which no statistically significant adverse effects were observed, and we compared them to regulatory predicted no effect concentrations for the protection of marine organisms, to assess whether these reference values are indeed protective of corals. Methods The evidence was taken from a systematic map of the impacts of chemicals arising from human activity on tropical reef-building corals published in 2021. All studies in the map database corresponding to the knowledge cluster “Evidence on the ecotoxicological effects of chemicals on corals” were selected. To identify subsequently published literature, the search was updated using a subset of the search string used for the systematic map. Titles, abstracts and full-texts were screened according to the criteria defining the selected cluster of the map. Because the eligibility criteria for the systematic review are narrower than the criteria used to define the cluster in the systematic map, additional screening was performed. Studies included were critically appraised and each study was rated as low, unclear, medium, or high risk of bias. Data were extracted from the studies and synthesised according to a strategy dependent on the type of exposure and outcome. Review findings The systematic review reports the known effects of chemical exposures on corals from 847 studies corresponding to 181 articles. A total of 697 studies (161 articles) were included in the quantitative synthesis and 150 studies (50 articles) in the narrative synthesis of the findings. The quantitative synthesis records the effects of 2706 exposure concentrations-durations of 164 chemicals or mixtures of chemicals, and identifies 105 toxicity thresholds corresponding to 56 chemicals or mixtures of chemicals. When toxicity thresholds were compared to reference values set for the protection of marine organisms by environmental agencies, the reference values appear to be protective of corals for all but three chemicals assessed: the metal copper and the pesticides diuron and irgarol 1051. Conclusions This open-access database of known ecotoxicological effects of chemical exposures on corals can assist managers in the ecological risk assessment of chemicals, by allowing easy determination of various ecotoxicological thresholds. Several limitations of the toxicity tests synthesised here were noted (in particular the lack of measurement of effective concentrations for more than half of the studies). Overall, most of the currently available data on coral toxicity should be replicated independently and extended to corals from less studied geographical regions and functional groups.