In This Issue

In This Issue Bruce Osborne Widow Spiders In Ireland, two species of the 'true' widow spiders (Latrodectus mactans (Fabricius) and L. geometricus) have previously been recorded. These are the spiders that produce a highly toxic neurotoxin that, in some cases, can cause temporary paralysis and even be fatal to humans. Thankfully, the evidence for permanent populations of these spiders is largely restricted to warmer regions of the world, although they may occur sporadically elsewhere as accidental introductions. Collier et al., in this issue, review the previous records for these species in Ireland and report on three new records of Latrodectus; two associated with retail outlets (L. geometricus) and one (L. hesperus) associated with the restoration of a food truck imported from California, where the progeny presumably survived during its transport to Ireland. Hitchhiking like this is a common feature of many marine introductions, either on ships or in ballast water, but this is an unusual example for a terrestrial species. Although there is still no evidence for the long-term survivorship of either species, the occurrence of L. hesperus in the former food truck for a period of approximately 20 months indicates that it survived two Irish winters outside of its normal climate range, possibly in a semi-dormant state. I think that this study illustrates how alien species may have the potential to establish outside their native range despite apparent climate-related constraints. In the future this may be exacerbated by rising temperatures and a further expansion in global trade. Microplastics and coastal lagoons Coastal lagoons, which occur at the interface of terrestrial and marine ecosystems, have special protection status due to the unique biota that they contain as well as their significance for tourism. Given their shallow characteristics, restricted water movement and their proximity to many urban areas, coastal lagoons are particularly susceptible to pollutants discharged from land-based anthropogenic activities. Of these pollutants, microplastic debris is increasingly recognised as an ever-present contaminant that has significant detrimental effects in many environments, often at a considerable distance from their source of production. However, as De Silva et al. indicate in this issue, less is known about the occurrence of microplastics in lagoons. Their review shows that lagoons can act as both an environmental source and a sink for microplastics and that a vast smorgasbord of different types are present in lagoon environments. Quantifying the amounts and impacts of different forms of microplastics present in lagoon environments, however, is difficult given the varied sampling and reporting methods that have been used in the past, with most studies focused on the occurrence and fate of microplastics in different lagoon habitats. Rather surprisingly, little is known about the extent of uptake of microplastics by humans and other organisms that use these environments, indicating that more work is required on their health-related impacts. Seeds for the future Seeds are not only an important source of food and essential oils, but they can also contain a variety of stimulants, medicines and spices. Seeds are the only way that the genetic information present in plants can be conveniently stored for future use in biodiversity or agronomic programmes. The identification and exploitation of genetic variation in seeds and how this relates to the establishment of plants for food, feed and fibre, is critical for their utilisation in agriculture and the food industry. One of the important seed characteristics is seed mass, as larger seeds are likely to be associated with better plant establishment and early growth, as they contain more resources. But to exploit this, there needs to be significant genetic variability in seed mass. To assess this Sanjani et al., in this issue, examined field collections and stored populations of Sanguisorba minor, an important source of fodder in Iran. They found that seed mass varied by approximately 7–10-fold, and this was positively correlated with seed longevity and the percentage of seeds that germinated, indicating the advantage of storing larger seeds for future breeding programmes. Seed mass was also related to several ecological variables, with smaller seeds in hotter and drier environments, but also wetter sites, indicating that both an excess and a shortage of water may have an impact on seed...