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Plant–herbivore–parasitoid systems are poorly studied in the tropics. Enicospilus carmenae Campos and Palacio sp. nov. are described, originating from southern Mexico in the Yucatan Peninsula and establishing a new tri-trophic interaction. This species is a koinobiont larval endoparasitoid of the American silkworm moth caterpillar Zanola verago (Cramer) (Lepidoptera: Apatelodidae) feeding on the shrub Piper neesianum C.DC. (Piperaceae) in a semi-evergreen forest. The host plant P. neesianum had no herbivore records to date, and a single collection event yielded the rearing of a new species of Enicospilus (Ichneumonidae, Ophioninae). Morphological, molecular (COI), biological, ecological, and geographical data are integrated to delineate the new species. 

The discovery of bioactive natural products is often challenged by the complexity of isolating and characterizing active compounds within diverse mixtures. Previously, we introduced a 1H NMR-based weighted gene correlation network analysis (WGCNA) approach to identify spectral features linked to growth inhibitory activity of Piper (Piperaceae) leaf extracts against model plant, fungal, and bacterial organisms. This method enabled us to prioritize specific spectral features linked to bioactivity, offering a targeted approach to natural product discovery. In this study, we validate the predictive capacity of the WGCNA by isolating the compounds responsible for the bioactivity-associated resonances and confirming their antifungal efficacy. Using growth inhibition assays, we verified that the isolated compounds, including three novel antifungal agents, exhibited significant bioactivity. Notably, one of these compounds contains a rare imidazolium heterocyclic motif, marking a new structural class in Piper. These findings substantiate the 1H NMR-based WGCNA as a reliable tool for identifying structural types associated with biological activity, streamlining the process of discovering bioactive natural products in complex extracts. 

Cationic water-soluble deep cavitands enable hierarchical assembly-based recognition, optical detection and extraction of perfluoroalkyl substances (PFAS) in aqueous solution. Recognition of the PFAS occurs at the lower rim crown of the cavitand, which triggers self-aggregation of a PFAS-cavitand complex, allowing extraction from water. In addition, when paired with an indicator dye that can be bound in the cavity of the host molecule, the PFAS-cavitand association causes a significant (>20-fold at micromolar [PFAS]) enhancement of dye fluorescence due to conformational rearrangement of the fluxional cavitand AMI, allowing optical sensing of PFAS. The cavitands are water-soluble, and the detection and recognition occur in purely aqueous solution. The association is most effective for long chain sulfonate PFAS, and as such, selective optical detection of perfluorooctanesulfonate is possible, with a LOD = 130 nM in buffered water, and 500 nM in real-world samples such as polluted canal water. By pairing the AMI host with multiple dyes in an array-based format, full discrimination of five other PFAS can be achieved at micromolar concentration via differential sensing. In addition, the aggregation process allows extraction of PFAS from solution, and a 99% reduction of PFOS concentration in water is possible with a single treatment of an equimolar concentration of AMI cavitand. The hierarchical nature of the cavitand recognition system allows both selective, sensitive optical detection and extraction of PFAS from water with a single scaffold. 

Climate-driven warming and changes in major ocean currents enable poleward larval transport and range expansions of many marine species. Here, we report the population genetic structure of the gastropodKelletia kelletii, a commercial fisheries species and subtidal predator with top-down food web effects, whose populations have recently undergone climate-driven northward range expansion. We used reduced representation genomic sequencing (RAD-seq) to genotype 598 adults from 13 locations spanning approximately 800 km across the historical and expanded range of this species. Analyses of 40747 single nucleotide polymorphisms (SNPs) showed evidence for long-distance dispersal ofK. kelletiilarvae from a central historical range site (Point Loma, CA, USA) hundreds of km into the expanded northern range (Big Creek, CA), which seems most likely to result from transport during an El Niño-Southern Oscillation (ENSO) event rather than consistent on-going gene flow. Furthermore, the high genetic differentiation among some sampled expanded-range populations and their close genetic proximity with distinct populations from the historical range suggested multiple origins of the expanded-range populations. Given that the frequency and magnitude of ENSO events are predicted to increase with climate change, understanding the factors driving changes in population connectivity is crucial for establishing effective management strategies to ensure the persistence of this and other economically and ecologically important species. 

Although infectious diseases play a critical role in population regulation, our knowledge of complex drivers of disease for insects is limited. We conducted a field study on Baltimore checkerspot caterpillars (Euphydryas phaeton), chemical specialists on plants containing iridoid glycosides (IGs), to investigate the roles of host plant, phytochemistry, ontogeny and spatial associations in determining viral prevalence. We analysed individuals for viral presence and loads, quantified leaf IG concentrations from their native and novel host plants, and sequestered IGs in caterpillars. We found proximate caterpillar groups had greater similarity in infection prevalence, with areas of high prevalence indicating viral hotspots. Underlying variation in host plant chemistry corresponded to differences in viral prevalence. Furthermore, we used structural equation modeling to examine causal drivers of infection prevalence and loads. Advanced ontogeny was associated with increased viral prevalence and loads, as well as decreased sequestration of IGs. Infection loads were lower on the novel host plant, but prevalence was slightly higher, partially explained by decreased sequestration of IGs. Altogether, our findings reveal that spatial proximity, ontogeny, host plant species and secondary phytochemistry can all contribute to structuring infection risk, and thus offer insight into causal drivers of disease prevalence in complex plant–insect systems. 

Controlling the reduction midpoint potential of heme B is a key factor in many bioelectrochemical reactions, including long-range electron transport. Currently, there are a number of globular model protein systems to study this biophysical parameter; however, there are none for large polymeric protein model systems (e.g., the OmcS protein from G. sulfurreducens). Peptide amphiphiles, short peptides with a lipid tail that polymerize into fibrous structures, fill this gap. Here, we show a peptide amphiphile model system where one can tune the electrochemical potential of heme B by changing the loading ratio and peptide sequence. Changing the loading ratio resulted in the most significant increase, with values as high as −22 mV down to −224 mV. Circular dichroism spectra of certain sequences show Cotton effects at lower loading ratios that disappear as more heme B is added, indicating an ordered environment that becomes disrupted if heme B is overpacked. These findings can contribute to the design of functional self-assembling biomaterials.