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Plant-lepidopteran interactions involve complex processes encompassing molecules and regulators to counteract defense responses they develop against each other. Lepidoptera identify plants for oviposition and exploit them as larval food sources to complete their development. In turn, plants adopt different strategies to overcome and limit herbivorous damages. The insect egg deposition on leaves can already induce a number of defense responses in several plant species. This minireview deals with the main features involved in the interaction between plants and lepidopteran egg-laying, focusing on responses from both insect and plant side. We discuss different aspects of direct and indirect plant responses triggered by lepidopteran oviposition. In particular, we focus our attention on the mechanisms underlying egg-induced plant defenses that can i) directly damage the eggs such as localized hypersensitive response (HR)-like necrosis, neoplasm formation, production of ovicidal compounds and ii) indirect defenses, such as production of oviposition-induced plant volatiles (OIPVs) used to attract natural enemies (parasitoids) able to kill the eggs or hatching larvae. We provide an overview of chemical, physiological, and molecular egg-mediated plant responses induced by both specialist and generalist lepidopteran species, also dealing with effectors, elicitors, and chemical signals involved in the process. Egg-associated microorganisms are also discussed, although little is known about this third partner participating in plant-lepidopteran interactions.

The striped dolphin (Stenella coeruleoalba) is one of the most abundant cetaceans of the Mediterranean Sea. Nevertheless, it is ranked as ‘Vulnerable’ by IUCN Red List experts. To implement conservation strategies within the Mediterranean Sea, it is crucial to understand how striped dolphins are distributed at different geographical scales. The present study investigates its distribution within the EU Adriatic and Ionian Sea Region. To model striped dolphin distribution, topographic (distance from shore, depth and slope) and oceanographic variables (sea surface temperature and phytoplankton concentration) were employed, and species distribution models (SDMs) were developed using Maxent software. Generalized additive models (GAMs) were used to improve the information supplied by the SDMs, allowing the description of response curves to striped dolphin occurrences. Statistical analysis shows that striped dolphins are not evenly distributed within the investigated area. The higher encounter rates observed in the Gulf of Taranto and the Gulf of Corinth confirm that both sub‐regions are crucial for its conservation. Furthermore, SDMs also indicate suitable areas in the offshore waters of the Adriatic Sea, along the continental slope of the north‐eastern Ionian Sea and over its continental shelf. Within the EU Adriatic and Ionian Sea Region, striped dolphins prefer areas at a greater distance from shore, with steeper slopes, deeper waters, and higher sea surface temperature. The topographic variables are the most explicative factors for both modelling approaches. The analysis of striped dolphin SDMs allows the identification of important areas for conservation and highlights zones where appropriate mitigation strategies could reduce the impact of human activities on this Vulnerable species. Further analysis of SDMs for different periods of the year, as well as a genetic study, could highlight seasonal movements across and within sub‐regions.

Loggerhead turtles Caretta caretta spend most of their life in large marine areas occupying a variety of habitats where they are exposed to different types of threats. Among these, marine litter poses a risk of entanglement or ingestion. Areas of risk exposure can be identified where the species overlap with litter accumulations, but gathering data on this highly mobile species and marine litter, especially in high sea areas, is challenging. Here we analysed 5 years of sea turtle and marine litter data collected by a network of research bodies along fixed trans-border transects in the Mediterranean Sea. Ferries were used as observation platforms to gather systematic data on a seasonal basis using standard protocols. Loggerhead turtle sightings over time and space were compared in terms of sightings per unit effort, and risk-exposure areas were assessed based on seasonal overlap of species hot spots and high-density plastic areas revealed by kernel analysis. In almost 180 000 km surveyed, 1258 sea turtles were recorded, concentrated mostly in the central Adriatic Sea and Sardinia-Sicilian channels during all seasons, and in the central Tyrrhenian Sea during spring. Plastic comprised the highest fraction of litter items detected. Several areas of higher risk exposure, both permanent and seasonal, were identified, mainly in the Adriatic Sea and during the spring−summer seasons. Records of both species and floating litter were highly variable, underlying the need for continuous long-term monitoring to develop sound conservation and management measures, especially in the identified areas of risk exposure.

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Although Caretta caretta is the most common turtle in the eastern Mediterranean Sea, its distribution is relatively difficult to assess due to the lack of data in offshore waters. The ecological niches in the central‐southern Adriatic Sea and the north‐eastern Ionian Sea were investigated for loggerhead turtles with body sizes ≥20 cm during two periods: winter (W), which includes months from October to March, and breeding–nesting (BN), from April to September. Differences in the spatial distribution of loggerheads were explored between periods, and the environmental predictors driving habitat selection were examined. Loggerheads mainly select habitats within the continental shelf (<200 m) differently, and exhibit: (i) a generalist behaviour in the Adriatic subregion during BN and a specific selection of environmental conditions during W; and (ii) a specialist behaviour in the Ionian Sea. The Adriatic niche appeared as an important foraging ground year‐round, whereas the distribution of suitable areas in the Ionian Sea is patchy and limited to specific habitats close to shore. Extreme values of sea surface temperatures (SSTs) from October to March (W) influenced loggerhead distribution differently in the subregions: areas experiencing cold and warm SST peaks were selected, respectively, in the Adriatic and Ionian subregions. Moreover, SST in April largely contributed to defining the habitat suitability in BN for both subregions This study further confirms the importance of the Adriatic and Ionian seas for the conservation of loggerhead sea turtles and the need for seasonal investigations to establish effective conservation measures. Here, the use of a cost‐effective method (fixed line transects from ferries) to inform the distribution of sea turtles in offshore waters is a valuable methodology for long‐term seasonal investigations of the habitat use of sea turtles.

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