Search Results (16)

Antarctic silverfish (Pleuragramma antarcticum) play a crucial intermediary role in connecting top predators and krill in the food web of the Antarctic Ocean. Despite their crucial role, research on their abundance is lacking. In this study, we estimated the abundance of juvenile Antarctic silverfish as foundational data for predicting their abundance. The density of juvenile Antarctic silverfish was estimated using an acoustic backscattering theoretical model. The mean volume backscattering strength was used to investigate the vertical and horizontal distributions of juvenile Antarctic silverfish in the Antarctic Ross Sea. The survey area was located near Cape Hallett, Antarctica, where Antarctic krill (Euphausia superba), ice krill (E. crystallorophias), and Antarctic silverfish coexist. The survey was performed four times using the Korean Antarctic research ship, RV Araon (R/V, 7507 GT). Frame trawls were conducted to identify the length and weight of the target fish species in the survey area. Captured Antarctic silverfish captured measured 3–9 cm. The maximum target strength (TS) was −92.93 dB at 38 kHz, −86.63 dB at 120 kHz, and 85.89 dB at 200 kHz. The average TS was −100.00 dB at 38 kHz, −93.00 dB at 120 kHz, and −106.90 dB at 200 kHz. Most juvenile Antarctic silverfish were found at a depth of 100 m and were distributed closer to sea ice. Between nearshore and polynya waters, the fish demonstrated a proclivity for polynya waters. Full article

The webbing clothes moth (Tineola bisselliella) causes extensive and costly damage to fabrics, furnishings, and museum objects. It is best known from its presence in homes, museums, and historic properties, while infestations in office buildings are not as well understood. Offices typically have more frequent cleaning, fewer quiet habitats, less food availability, and fewer breeding environments for moths, which may explain the lower abundance. Nevertheless, they can be introduced with materials or by employees whose homes have a moth infestation. This study examines the distribution of different insect pests determined from pheromone traps set out in an unoccupied multi-floor office building in Switzerland. Tineola bisselliella dominated the insect catch but was mostly found in the aisles on the lower floors. The larger rooms tended to have a greater insect catch. Carpet beetles (Attagenus smirnovi) and silverfish (Zygentoma) were also found, although in smaller numbers, and often preferred the basement floors. The ghost silverfish (Ctenolepisma calvum) dominated the Zygentoma, even though it has been rare until recently in Switzerland. The study suggests the need for Integrated Pest Management within office buildings. In addition, in unoccupied buildings under renovation, with no obvious sources of food, insect pests still need monitoring. Full article

The Mediterranean Basin is considered one of the most important hotspots of biodiversity in the European region. Many taxa exhibit high levels of speciation and endemicity in this area. This is the case of the myrmecophilous insects of the families Lepismatidae and Nicoletiidae (Insecta: Zygentoma) that are further assessed in this study using unpublished and bibliographic data. A complete checklist of all ant-associated silverfish occurring in the Mediterranean Basin is presented, together with an updated identification key and interesting new records for several countries. Considering all described Zygentoma species, the myrmecophilous silverfish of the Mediterranean area represent 28% of all ant-associated species of the world and about 35% of the studied area. Even with the scarce knowledge of Zygentoma in other biogeographic areas and with insufficient sampling in other continents, we conclude that the Mediterranean region, and neighbouring areas of the Western Palaearctic, represent the most important biodiversity hotspot of ant-associated Lepismatidae (about 30% of the myrmecophilous species of this family described in the world so far), while the highest diversity of myrmecophilous Atelurinae is linked to tropical regions. Full article

The COVID-19 pandemic led to significant changes in societies across the globe. In many countries in Europe, national lockdowns during the spring of 2020 meant that museums were closed, and maintenance and housekeeping were at a minimum. We compared the insect monitoring data of 15 museums in and around Vienna between the years 2018 and 2022 to see potential effects of the two lockdowns (spring 2020 and winter 2020/21) on insect populations. In Vienna, these changes altered the presence of pests, most notably an increase in silverfish by late spring (March–May 2020). We also found increased numbers of other pest species (notably Tineola bisselliella and Attagenus sp.), though these changes were seen later (June–October 2020). Thylodrias contractus, although found only in one museum, appeared to show decreased numbers during 2020. Storage areas in some of the museums revealed no significant increase in insect catch during the COVID-19 related closures. Since there are rarely visitors in such spaces, the situation did not change much during the closures. Silverfish are shy insects, but they were able to range more freely during the closures in the mostly darkened rooms. The increase of Tineola bisselliella and Attagenus sp. could be a result of reduced cleaning in the first lockdown. In the second lockdown, no significant changes were found. Human activity from staff was much higher compared to the first closure; a second reason could be the time of year, as in the winter period, it is mainly larvae that are active. Increased insect populations remind us that even when museums are unoccupied, they still need monitoring for possible risks from pests. No damage to the objects from the pests was observed in the museums investigated. Full article

The abundance of insect and fungal pests under a changing climate may threaten historic interiors, libraries and museums, with warmer, potentially more humid winters. This work examines local and indoor climate, insects and fungi in a historic library near Vienna. It reveals a mostly dry and cool environment for the storage of books, but few visitors to induce changes. Temperature and relative humidity have been monitored for 12 months (2021-07/2022-07), with 14 monitors positioned insect traps (blunder traps and some pheromone traps). Fungi in air, on surfaces and in settled dust were also sampled. Winter temperatures in library cupboards and behind shelves were slightly warmer (~1 °C) and more humid than in the library environment. Over the last decade there have been infestations of the biscuit beetles (Stegobium paniceum) but since treatment with sulfuryl difluoride, Anthrenus sp. have dominated. Silverfish are also present, but only in one corner. Fungal outbreaks have also been found, but over five years fungi in air samples have shifted from Penicillium commune and P. chrysogenum to Aspergillus sp. The stable environment at Klosterneuburg is suitable for books, yet insects and mould present suggests vigilance remains necessary, as some microenvironments (e.g., cupboards) can be at risk and there may be materials with high water content, hygroscopic or of nutritional value. Full article

The fatty acid profile of seven different organs (brain, gills, heart, muscles, gonads, liver, and gall bladder) of the lipid-rich Antarctic silverfish, Pleuragramma antarcticum, from the Antarctic Sound was studied. Qualitative and quantitative analyses of fatty acids were performed using gas chromatography with mass-selective and flame ionization detectors. It was seen that the muscles and gills differed from the other organs with the prevalence of saturated fatty acids, mainly due to 16:0 and 14:0 that may reveal their additional metabolic role in these organs for adaptation of the fish to the cold Antarctic waters. Monounsaturated fatty acids 18:1(n − 9) and 16:1(n − 7) were prevalent in the other organs of silverfish, especially their high content in the liver, reflecting the carnivorous feeding type (mainly adult ice krill) of the species and their dietary preferences in the austral summer. The high content of essential fatty acids, 22:6(n − 3) (14% of total fatty acids) found in the brain and 20:5(n − 3) (12% of total fatty acids) found in the muscles, highlights the functional significance of these lipid components in the studied tissues of fish. The results will improve the understanding of the functional value of individual fatty acids in terms of their organ specificity and the adaptation of the Antarctic silverfish to life in the frigid ice waters of the Antarctic pelagic ecosystem. Full article

Ctenolepisma calvum was first described in Sri Lanka (Ceylon) in 1910, and this island is probably the origin of this species. Later, it was also found in the Caribbean (Cuba and Trinidad and Tobago). Up until the present, it has only been identified within buildings (a synanthropic species), and its natural habitat is unknown. In 2007, it was discovered in Germany and was considered a neobiotic species of Lepismatidae in Europe. It has rapidly spread throughout Europe and beyond in recent years. This led us to analyze the available data of the first occurrences in Germany, Austria, and other European countries. Furthermore, we compared the spread inside of museums in Vienna (Austria) and Berlin (Germany). These museums have been monitored for a long period with sticky traps, representing the best source of information on the dispersion dynamics of Ctenolepisma calvum. We found a scattered occurrence of this species in 18 countries in Europe (including Russia and Ukraine). The first record for Poland has not previously been published; however, this species has been present there since 2014. Surprisingly, it was found in Hungary in 2003, but a record was only published online in 2021. Additionally, in Germany and Austria, where most data are available, the spread of the species does not follow any clear pattern. In museums in Berlin, the species has only been found in one location. In contrast, the species rapidly spread in museums in Vienna between 2014 and 2021, from four to 30 locations, and it is now a well-established species with occasional high abundance. We examined the spread of the species at three spatial scales: (i) Europe, (ii) national, and (iii) regional. Our observations indicate that it is possibly distributed with materials (packaging material, hygiene articles, paper, cardboard, and collection items). Little is yet known about the biology of this introduced pest. We describe its preferred habitat within buildings, its climate requirements, and its potential to act as a new museum pest in Central Europe. This species seems to thrive at room temperature in buildings. Further impact on the species due to climate change in the future is also discussed. We offer a simple morphological key and a detailed identification table to help correct species identification. Full article

Climate change not only affects the biodiversity of natural habitats, but also the flora and fauna within cities. An increase in average temperature and changing precipitation, but additionally extreme weather events with heat waves and flooding, are forecast. The climate in our cities and, thus, also inside buildings is influenced by the changing outdoor climate and urban heat islands. A further challenge to ecosystems is the introduction of new species (neobiota). If these species are pests, they can cause damage to stored products and materials. Much cultural heritage is within buildings, so changes in the indoor climate also affect pests (insect and fungi) within the museums, storage depositories, libraries, and historic properties. This paper reviews the literature and presents an overview of these complex interactions between the outdoor climate, indoor climate, and pests in museums. Recent studies have examined the direct impact of climate on buildings and collections. The warming of indoor climates and an increased frequency or intensity of extreme weather events are two important drivers affecting indoor pests such as insects and fungi, which can severely damage collections. Increases in activity and new species are found, e.g., the tropical grey silverfish Ctenolepisma longicaudatum has been present in many museums in recent years benefitting from increased indoor temperatures. Full article

The olfactory system is constituted in a consistent way across vertebrates. Nasal structures allow water/air to enter an olfactory cavity, conveying the odorants to a sensory surface. There, the olfactory neurons form, with their axons, a sensory nerve projecting to the telencephalic zone—named the olfactory bulb. This organization comes with many different arrangements, whose meaning is still a matter of debate. A morphological description of the olfactory system of many teleost species is present in the literature; nevertheless, morphological investigations rarely provide a quantitative approach that would help to provide a deeper understanding of the structures where sensory and elaborating events happen. In this study, the peripheral olfactory system of the Antarctic silverfish, which is a keystone species in coastal Antarctica ecosystems, has also been described, employing some quantitative methods. The olfactory chamber of this species is connected to accessory nasal sacs, which probably aid water movements in the chamber; thus, the head of the Antarctic silverfish is specialized to assure that the olfactory organ keeps in contact with a large volume of water—even when the fish is not actively swimming. Each olfactory organ, shaped like an asymmetric rosette, has, in adult fish, a sensory surface area of about 25 mm², while each olfactory bulb contains about 100,000 neurons. The sensory surface area and the number of neurons in the primary olfactory brain region show that this fish invests energy in the detection and elaboration of olfactory signals and allow comparisons among different species. The mouse, for example—which is considered a macrosmatic vertebrate—has a sensory surface area of the same order of magnitude as that of the Antarctic silverfish, but ten times more neurons in the olfactory bulb. Catsharks, on the other hand, have a sensory surface area that is two orders of magnitude higher than that of the Antarctic silverfish, while the number of neurons has the same order of magnitude. The Antarctic silverfish is therefore likely to rely considerably on olfaction. Full article

COVID-19 spread globally and, as there was little immunity, quarantine, isolation, and social distancing became widely practiced. As people were restricted to their homes in many countries, public venues, such as museums, galleries, and historic houses, were typically closed. This allowed insect abundance, under changed conditions, to be explored using traps from the Technical Museum, Schönbrunn Palace, Hofburg Museum, and Weltmuseum in Vienna. The trap contents reveal an increase in Lepisma saccharinum, the common silverfish, as well as in the Zygentoma Ctenolepisma longicaudatum and C. calvum at some museums. Other insects such as Tineola bisselliella, Anthrenus verbasci, and Attagenus smirnovi, though found in reasonable numbers, did not increase. Museum interiors were likely a little cooler and drier during lockdown, but this difference is too small to explain the increased silverfish activity. The larger rooms were certainly quieter, which allowed insects freedom to range more widely. Nevertheless, museums did not observe increased damage to collections from the larger numbers. The infestations during the closures suggest a need for low level cleaning and regular inspections, with an initial focus examining those areas frequented by insects in the past. Full article

To identify the dietary composition and characteristics of both Adélie (Pygoscelis adeliae) and Emperor (Aptenodytes forsteri) penguins at four breeding sites, we performed stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope analysis of down samples taken from penguin chicks. Adélie Penguin chicks at Cape Hallett mostly fed on Antarctic krill (Euphausia superba; 65.5 ± 3.5%), a reflection of the prevalence of that species near Cape Hallett, and no significant differences were noted between 2017 and 2018. However, Adélie Penguin chicks at Inexpressible Island, located near Terra Nova Bay, fed on both Antarctic silverfish (Pleuragramma antarctica; 42.5%) and ice krill (Euphausia crystallorophias; 47%), reflecting the high biomass observed in Terra Nova Bay. Meanwhile, no significant difference was noted between the two breeding sites of the Emperor Penguin. Emperor Penguin chicks predominantly fed on Antarctic silverfish (74.5 ± 2.1%) at both breeding sites (Cape Washington and Coulman Island), suggesting that diet preference represents the main factor influencing Emperor Penguin foraging. In contrast, the diet of the Adélie Penguin reflects presumed regional differences in prey prevalence, as inferred from available survey data. Full article

Synanthropic invasive silverfish, Ctenolepisma longicaudatum, has been recently reported to cause nuisance in the indoor environment in many European countries. To get more details on the species distribution, the species occurrence was monitored by the authors in the countries where establishment of C. longicaudatum has been revealed in the last years. In Czechia, 20 findings from 14 municipalities in eight regions were recorded within the last three years. In the United Kingdom, 49 cases, including the first occurrence in Scotland, were recorded. Five cases were recorded for the Republic of Ireland. Domestic settings were the main habitat in the study countries (50.0% for the Czechia and Ireland and 36.8% for the United Kingdom). Regarding C. longicaudatum control, the standard silverfish strategy fails, and the use of insecticidal baits complemented by dust insecticides was suggested as the most promising approach. To reveal presence of C. longicaudatum in Europe, the search of literature, social platforms and databases on invasive species was conducted. According to these sources, the species is known from majority of European countries, when the high increase of records in recent decade was detected. Full article

Sistema Huautla is the deepest cave system in the Americas at 1560 m and the fifth longest in Mexico at 89,000 m, and it is a mostly vertical network of interconnected passages. The surface landscape is rugged, ranging from 3500 to 2500 masl, intersected by streams and deep gorges. There are numerous dolinas, from hundreds to tens of meters in width and depth. The weather is basically temperate subhumid with summer rains. The average yearly rainfall is approximately 2500 mm, with a monthly average of 35 mm for the driest times of the year and up to 500 mm for the wettest month. All these conditions play an important role for achieving the highest terrestrial troglobite diversity in Mexico, containing a total of 35 species, of which 27 are possible troglobites (16 described), including numerous arachnids, millipedes, springtails, silverfish, and a single described species of beetles. With those numbers, Sistema Huautla is one of the richest cave systems in the world. Full article

Pest management strives to be an efficient, yet healthy and environmentally safe control method, and the use of poisoned bait often fulfils these criteria. In the present study, we show that bait with indoxacarb as the active ingredient is highly efficient for controlling Ctenolepisma longicaudata (Escherich, 1905) and two of its relatives, Lepisma saccharina (Linnaeus, 1758) and Ctenolepisma calva (Ritter, 1910). Applying small bait droplets (size ~10 mg) along the walls of several types of buildings, at no more than 0.5 to 1.0 g bait per 100 m², was a cost-efficient and safe strategy for the knockdown and eradication of C. longicaudata. During field experiments, the demography changed from an initial mixture of different stages to total dominance of early instars preceding the population collapse. Poisonous bait outcompeted mass-trapping with sticky-traps and conventional insect spray treatment for the efficient control of C. longicaudata in apartments. Different droplet densities (1 vs. 0.5/m²) and active ingredients (indoxacarb vs. clothianidin) did not have different effects in field experiments. These results show that poisoned bait is a highly relevant tool for managing C. longicaudata and potentially against other silverfish infestations. Full article

The long-tailed silverfish (Ctenolepisma longicaudata) has recently made its appearance and demonstrated a tremendous proliferation in Norway, where it is currently considered a major indoor nuisance pest in modern buildings. To reduce the risk of human pesticide exposure, several baits with indoxacarb, clothianidin, fipronil or imidacloprid as the active ingredient were investigated to provide knowledge regarding their potential for integrated pest management solutions. Primary and secondary poisoning, as well as the durability of baits, were experimentally evaluated in bioassays. Baits with indoxacarb, clothianidin and fipronil killed more than 90% of the experimental insects (primary poisoning) when presented in competition with food. Only indoxacarb produced high mortality when dead conspecifics were consumed (secondary poisoning) and resulted in more than 75% mortality. The efficacy of baits with indoxacarb against C. longicaudata was also found to be very long. Laboratory degraded baits were consumed and induced high levels of mortality for more than a month, and field degraded baits for more than 6 months. Adults and juveniles were equally affected in the experiments. Primary and secondary toxicity in combination with long durability and effects on both life stages tested suggest that the bait has high-level potential as a safe control strategy against the long-tailed silverfish if indoxacarb is used as the active ingredient. Full article