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The impaired activity of tyrosinase and laccase can provoke serious concerns in the life cycles of mammals, insects and microorganisms. Investigation of inhibitors of these two enzymes may lead to the discovery of whitening agents, medicinal products, anti-browning substances and compounds for controlling harmful insects and bacteria. A small collection of novel reversible tyrosinase and laccase inhibitors with a phenylpropanoid and hydroxylated biphenyl core was prepared using naturally occurring compounds and their activity was measured by spectrophotometric and electrochemical assays. Biosensors based on tyrosinase and laccase enzymes were constructed and used to detect the type of protein-ligand interaction and half maximal inhibitory concentration (IC50). Most of the inhibitors showed an IC50 in a range of 20–423 nM for tyrosinase and 23–2619 nM for laccase. Due to the safety concerns of conventional tyrosinase and laccase inhibitors, the viability of the new compounds was assayed on PC12 cells, four of which showed a viability of roughly 80% at 40 µM. In silico studies on the crystal structure of laccase enzyme identified a hydroxylated biphenyl bearing a prenylated chain as the lead structure, which activated strong and effective interactions at the active site of the enzyme. These data were confirmed by in vivo experiments performed on the insect model Tenebrio molitur.

Type specimens of Neotropical Chrysopidae are currently held in two Italian natural history museums. Four are in the Museo Regionale di Scienze Naturali (MRSN), Torino, and five are in the Museo Civico di Storia Naturale “Giacomo Doria” (MSNG), Genova. Together, these nine specimens also represent all of the known New World types of Chrysopidae housed in Italian museums. All were described by Longinos Navás between 1922 and 1932, and all are now in relatively good condition. Here, we catalog and provide images of each specimen, designate lectotypes, and offer current taxonomic and nomenclatural information on the species represented by each. Two nomenclatural changes are proposed: (1) Chrysopa mainerii Navás, 1929, previously considered incertae sedis, is synonymized with Ceraeochrysa everes (Banks, 1920), n. syn.; (2) Chrysopa barberina Navás, 1932, also previously incertae sedis, is identified as Chrysoperla barberina (Navás, 1932), n. comb.

Se aportan nuevos datos de 41 especies de crisópidos de las Faunas Ibérica, Balear y Canaria. Se redescribe la morfología externa y genital de Chrysopa nigricostata Brauer, 1850 y se corrigen sus citas erróneas de España y Portugal, que mayoritariamente se asignan a Cunctochrysa cosmia (Navás, 1918). Se revalida la especie Chrysopa cosmia Navás, 1918 estatus válido restaurado (antes sinónima posterior de Chrysopa nigricostata) y se transfiere al género Cunctochrysa, proponiéndose una nueva combinación: Cunctochrysa cosmia (Navás, 1918) n. comb., y una nueva sinonimia: Cunctochrysa cosmia (Navás, 1918)=(Cunctochrysa bellifontensis Leraut, 1988) n. sin. Sobre el único ejemplar hasta ahora conocido de Cunctochrysa cosmia y el nuevo material ahora a ella asignado, se redescribe su morfología externa y genital, aportándose una clave de identificación para las tres especies europeas del género Cunctochrysa, anotándose nuevos datos para diferenciarlas tanto entre sí, como de otras especies europeas de similar morfología y coloración (Pseudomallada flavifrons, Chrysopa viridana y especialmente C. nigricostata). Por estas similitudes, se detectan algunos errores en la identificación de estas especies, se llama la atención sobre la posible confusión entre estas especies, y se sugiere revisar la autenticidad de sus sinonimias propuestas. Se establecen dos nuevas combinaciones: Pseudomallada subcostalis (McLachlan, 1882) n. comb. y Pseudomallada fortunatus (McLachlan, 1882) n. comb.

Global plant trade represents one of the main pathways of introduction for invertebrates, including insects, throughout the world. Non-native insects include some of the most important pests affecting cultivated and ornamental plants worldwide. Defining the origins and updating the distribution of non-native invasive species is pivotal to develop effective strategies to limit their spread. The agave weevil, Scyphophorus acupunctatus (Coleoptera, Dryophthoridae), is a curculionid beetle native to Central and North America, although it also occurs in Eurasia, Africa, Oceania and South America as a non-native species. Despite being widespread, the extent of occurrence and origins of European populations of the agave weevil have been overlooked. In the present study, the current and potential worldwide distribution of S. acupunctatus was assessed and an analysis of its genetic diversity in the native and non-native ranges was performed. By analysing occurrences from local phytosanitary bulletins and citizen-science platforms, the agave weevil was confirmed to be widely distributed and to occur on all continents, except Antarctica. Additionally, there is potential for expansion throughout the world, as estimated by species distribution models. Nucleotide and haplotype diversity of the COXI mitochondrial gene (about 650 bp) was lower in the non-native (n = 39 samples) than native populations (n = 26 samples). The majority of introduced individuals belonged to the same haplotype, suggesting that most introductions in Europe might have occurred from a small geographical area in Central America. Constant transboundary monitoring and national laws must be considered to reduce the spread of the agave weevil, given that a bridgehead effect may occur from non-native populations to new suitable areas.

Halyomorpha halys (Stål) (Hemiptera, Pentatomidae) was accidentally introduced to North America and Europe, becoming a key pest of many important crops. In its native range, it is attacked by egg parasitoids, including Trissolcus japonicus (Ashmead), considered to be the main species, and T. mitsukurii (Ashmead) (Hymenoptera, Scelionidae). Trissolcus japonicus was detected in North America in 2014 and Europe in 2017, while T. mitsukurii was detected in Australia in the early 20th century and in Europe in 2016. Both species now appear established in the new areas. The present study used the MaxEnt algorithm to clarify the geographic dimension of the potential interaction between H. halys and these two parasitoid species, and to indicate where the release of one or the other parasitoid species is more likely to be effective. We found that the suitability for the two parasitoids overlaps the H. halys native range completely. In invaded areas, T. japonicus showed higher potential habitat suitability at the global scale, compared to T. mitsukurii, and also higher potential suitability at lower latitudes at continental and national scales. These results can substantially improve the effectiveness of biological control against H. halys, by targeting the releases of parasitoids to the areas where each species is most likely to succeed.