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Pomphorhynchus laevis is a freshwater heteroxenous parasite that infects Gammarus pulex as intermediate host and Squalius cephalus as definitive host. This acanthocephalan parasite is able to manipulate the behavior of G. pulex to increase probability of transmission between G. pulex prey and S. cephalus predator. Manipulation results from complex interactions and could be triggered or enhanced by biotic parameters. This experimental study investigated the effect of the presence both of G. pulex conspecifics and of S. cephalus cues on the behavior of P. laevis-infected and uninfected G. pulex in flowing water. The presence of G. pulex conspecifics increased the distance covered by both uninfected and P. laevis-infected gammarids in the artificial stream, whereas S. cephalus cues did not influence the distance covered by either. In static water, S. cephalus cues significantly decreased G. pulex attraction to light, regardless of infection status. Our results show that P. laevis manipulates distance covered regardless of the presence of either G. pulex conspecifics or S. cephalus cues. We discuss how these two biological parameters affect uninfected G. pulex and other factors involved in P. laevis manipulation of its gammarid host.

Although the biology of cicadas is generally well known, knowledge about their exuviae is limited. The exuviae of the Kaempfer cicada is covered with soil, but the exuviae of the black giant cicada has almost no soil attached to it. We have focus on the surface structure of cicada exuviae, especially the soil adhesion and water repellency of the exuviae surface. The substance that adheres the soil to the exuviae surface of the Kaempfer cicada was extracted and isolated. We found that mucin contributes to the soil adhesion of the larvae surface of the Kaempfer cicada. The surface of the Kaempfer cicada shell has more hairs than that of the black giant cicada, also contributing to soil adhesion. We also show the abdominal part of the exuviae of both species exhibiting water repellency. The fact that water repellency located around the spiracles suggests that it is a feature that ensures breathing. Interestingly, the structure of this part was similar to that of the surface of a lotus leaf.

Darwin wasps (Hymenoptera: Ichneumonidae) are among the most diverse and ecologically important groups of parasitoid insects, with more than 25,000 valid species and many more yet to be discovered. As the most speciose family within the order Hymenoptera, their remarkable evolutionary success is primarily attributed to their parasitic life history, which enables them to exploit a vast array of hosts and ecological niches. Despite their pivotal role in regulating host populations and maintaining ecosystem balance, host association data for Ichneumonidae remain significantly underexplored. This article presents IchHostBR, a comprehensive dataset compiling host-parasitoid records for Brazilian Darwin wasps. The dataset integrates 342 host-parasitoid associations sourced from 156 journal articles, encompassing 16 subfamilies, 74 genera, and 93 species of Ichneumonidae, as well as six host orders and 121 host species. The methodology involved rigorous data collection, cleaning, and standardization ensuring accuracy and usability. The primary aim of this initiative is to establish a robust, accessible, and continuously updated online platform that supports research and conservation efforts. In addition to introducing the dataset, the article provides a state-of-the-art review of current knowledge on Ichneumonid host associations, identifies key gaps in our knowledge and hopefully lays a foundation for advancing studies on Ichneumonidae host interactions in Brazil.

A left–right asymmetry of plants has attracted attention in various study areas (e.g., developmental biology, ethology, and evolutionary biology); however, the underlying mechanisms remain unclear. In the genus Arisaema (Araceae), each plant possesses a cylindrical spathe that exhibits the left–right-handedness in the folding direction. As the spathe is a modified leaf, a phyllotactic spiral (clockwise or counter-clockwise directions) in vegetative organs may affect this dimorphism. In this study, we aimed to examine (1) interannual changes in the spathe folding direction in the same individuals, (2) the effect of phyllotactic spirals on the left–right-handedness of the spathe, (3) the abundance ratio of left- and right-folded spathes in several Arisaema species, and (4) the relationship between the coiling direction of young folded leaves and phyllotactic spirals in other aroid genera. The spathe folding direction changed annually and was significantly related to the phyllotactic spiral direction. The left–right-handedness prevailed among the 27 tested Arisaema species, and frequencies of left- and right-folded spathes were mostly similar. In the five aroid genera, the phyllotaxis was clearly correlated with the leaf coiling direction. These results imply that the phyllotactic spiral affects the spathe folding direction of Arisaema and the leaf coiling direction of aroids. Considering developmental studies on asymmetric leaves in other taxa, the left–right-handedness of the spathe in Arisaema is possibly a consequence of the phyllotactic pattern formation.

Western Natal green snakes (Philothamnus occidentalis) are a relatively common and widely distributed snake across the eastern half of South Africa. Little is known about their reproduction other than information that has been gleaned from others in the genus. We document several separate cases of communal breeding, as well as both aggressive and reproductive visual communication, all of which are new information for this species. This study also documents a breeding event for the eastern Natal green snake (Philothamnus natalensis), which shows different behaviours supporting the recent species split.

Timber adulteration, illegal harvesting, and logging of legally protected timber species are a major threat to biodiversity. Identifying and differentiating low-value timber species from high-grade ones is a prerequisite to combat timber-related crimes. Timber adulteration can be detected by techniques such as DNA barcoding. However, these techniques have some drawbacks as they are time-consuming and destructive. To address all these issues, in this study, a quick and non-destructive approach has been used to detect timber adulteration by identifying and discriminating selective timber species using vibrational spectroscopy along chemometric methods such as principal component analysis (PCA), linear discriminant analysis (LDA), and partial least square discriminant analysis (PLS-DA) that successfully differentiated Tectona grandis (teak) from Magnolia champaca (champ) with 96.25% accuracy, Swietenia macrophylla (mahogany) from Magnolia champaca with 97.5% accuracy, and Artocarpus heterophyllus (Jack) from Mangifera indica (mango) with 100% PCA LDA training accuracies. Partial least square discriminant analysis successfully differentiated the timber species with 100% accuracy. ATR-FTIR spectroscopy and chemometric tools proved to be effective in detecting timber adulteration, which will help the investigating agencies combat timber-related crimes.

Insect pollination is critical for the reproduction of crops and wild plants, yet the efficiency of pollinators varies widely across species. Hence, it is essential to study the visitation behavior and pollination effectiveness of the floral visitors. Neustanthus phaseoloides is an agro-ecologically and medicinally important plant occurring in Tripura, Northeast India. We selected it for the present investigation as its distinct floral morphology might impact the pollinator visitation behaviors and subsequent pollination success. A total of 12 insect foragers visited the flowers of N. phaseoloides. Among them, 10 generalist pollinators were observed depositing conspecific pollen along with some amount of heterospecific pollen grains on the stigma. Although the pollen deposition efficiency varied significantly among pollinator species, the bees were the most effective in pollen deposition and subsequent reproductive outputs. All pollinators contributed to the fruit and seed production at varying degrees, indicating their effectiveness in reproductive success. The mating system studies indicated that the species was self-compatible and dependent on pollinators for increased reproductive success. Furthermore, some degree of pollination deficit was detected in our study population, suggesting that the increased visitation of effective pollinators might enhance the reproductive outputs. Overall, this first report on the pollination effectiveness of N. phaseoloides will improve our understanding of the reproductive success in a medicinally useful wild plant.

Object identification is fundamental to animal behaviour and identifying nutritive objects is key for survival. Solitary insects emerging far from food sources and without access to social learning must therefore employ innate identification of food cues to locate relevant nutritive objects from a distance. Such innate preferences for food cues should be both specific enough to allow discrimination between food and non-food objects and general enough to allow for the variety of food objects relevant to the insect species. Here, we examined innate floral object identification behaviour in solitary generalist insect pollinator Eristalinus aeneus using an artificial floral object with both visual and olfactory cues previously found to be attractive to several hoverfly species across multiple environments. We used a subtractive two choice assay to present flower-naïve E. aeneus with a choice between this object and a similar object that differed in either a single visual or olfactory cue. We found that innate floral choices of the hoverfly E. aeneus are a product of broad, plant-based olfactory cues and visual cues, where a combination of radial symmetry and reflectance in the 300–400 nm and 500–700 nm wavelength range was particularly important for innate floral object preference. Our study, therefore, shows how solitary animals without prior experience can efficiently employ multimodal cues to identify multiple relevant nutritive objects.

The frog leg industry relies on a global, largely underregulated market with potentially important ecological impact such as the uncontrolled harvest of declining wild populations and the introduction of invasive species. Here, we inferred the taxonomic nature and geographic origins of frog legs imported to Switzerland by DNA barcoding. Out of 34 samples, we retrieved eight distinct lineages attributed to five species from four genera, namely Hoplobatrachus rugulosus from Vietnam, Fejervarya cancrivora from Indonesia (invasive on several Pacific islands), two phylogeographic lineages of Limnonectes macrodon from Western and Central Java, L. kadarsani from eastern Indonesia, and three phylogeographic lineages of Pelophylax ridibundus from northern and central southern Turkey (invasive in Western Europe). Only the first two species were correctly declared, which is particularly problematic to track down harvests of the declining and geographically restricted Limnonectes taxa. In this respect, we show that the three Asian genera can be reliably distinguished by basic measurements of the frog legs, which could be used in future forensic controls. Our study calls for more stringent international regulations of the frog trade, including shipment monitoring to document the relative abundance of harvested species and ensure the sustainability of their wild populations.