Three new species of Anapistula Gertsch, 1941, all found in caves in the state of Minas Gerais, Brazil, are described: Anapistula serpentina sp. nov. (♂♀), A. barbara sp. nov. (♂♀), and A. minadopico sp. nov. (♂♀). In addition, the known distribution range of Symphytognatha carstica Brescovit, Álvares & Lopes, 2004 is expanded. An updated distribution map for all known species of Anapistula in Brazil is provided.

A new genus and species of Theridiinae (Theridiidae), Anttheridion demerodei gen. et sp. n., is described on material from canopy samples in the Mayombe Province in Western DR Congo. The species has a striking ant-like appearance and is characterized by the shape of the carapace with a closed tube shaped posterior extension and the sclerotized abdominal ring around the pedicel in males. The female epigyne has a single copulatory opening and a single first part of the copulatory ducts.

The diet of the harvestman Leiobunum formosum (Opiliones, Sclerosomatidae) was investigated using observations of foraging individuals, feeding trials, scanning electron microscopy of faecal samples, and stable isotope data. In the field, harvestmen were rarely observed feeding (only eight out of 351 observations) but, when provided with different types of food, showed a significant preference for sliced fruit over acorns, pokeweed berries, or rocks (negative control). Laboratory feeding trials indicated that L. formosum would readily feed on a variety of plant, animal, and fungal foods. SEM examinations of 81 faecal pellets from field-collected adults revealed considerable variety in the diet, including evidence of herbivory, fungivory, fragments of arthropods, and stiff bristles of annelids. The occurrence of identifiable remains of these food items indicates that these harvestmen lack the capacity to digest cellulose or chitin completely. Our stable isotope analyses indicate that L. formosum is a generalist forager, with a large degree of variability among individuals. Mean δ15N signatures were similar to that observed for syntopic spiders, indicating carnivory. However, individuals ranged from feeding on a mix of plant and animal foods at the low end of the range to consuming a mixture of herbivorous and carnivorous invertebrates at the high end of the range. Overall, our results suggest that it is advisable to utilize a variety of complementary approaches for diet investigations.

The pseudoscorpion genus Trichernes Harvey, 2025 is endemic to New Caledonia and represented by three described species from montane habitats. A fourth species, Trichernes caliginosus sp. nov., is described from a rainforest habitat in southern New Caledonia that was collected using canopy fogging.

Many factors influence the expression of life-history traits, such as reproduction, in animals. Trade-offs in reproductive investment between offspring size and number have been described under the theory of r and K selection. Here, we examined offspring size and number in two large, synanthropic spiders that co-occur in urban habitats in the Netherlands. The false wolf spider Zoropsis spinimana (Zoropsidae) does not make a web and, over the course of a season, mothers construct several egg sacs on the ground under objects such as rocks. Upon hatching, the young spiderlings are left to fend for themselves and disperse. By contrast, the green-fanged tube spider Segestria florentina (Segestridae) lives in webs in crevices where the mother usually produces a single egg sac early in the year. Neonate spiderlings stay in the web for up to several weeks, scavenge on her prey, or may even consume her (matriphagy). Mean brood size, total number of egg sacs per mother, and the number of live, dead (and total) progeny, was much smaller in Z. spinimana than in S. florentina. However, neonate Z. spinimana spiderlings were much larger than neonate S. florentina spiderlings. This reveals that the two species differentially optimize reproductive investment in offspring size and number. Newly hatched offspring of the former species are relatively well developed and motile (i.e. exhibit traits of K-selection) whereas newly hatched offspring of the latter species are less well developed. (i.e. exhibit traits of r-selection). We discuss potential factors underlying reproductive investment strategies and resource-related trade-offs in spiders.

This paper is devoted to the history of the spider collections held at the Manchester Museum, UK. By the end of 2024, the Manchester Museum had accumulated over 172,000 spider specimens belonging to 4255 identified and around 1130 (21%) undetermined species. The history of the Museum's spider collections is narrated in the form of short essays focusing on specific araneologists who have donated significant (over 1000 specimens) spider collections. Smaller acquisitions of tens/hundreds of specimens (130 in total) are dealt with in a separate section. A complete catalogue of the type specimens of Araneae in the Manchester Museum (to the end of 2024) is also provided. A total of 179 spider species (746 specimens) are represented by type specimens, of which 71 species are represented by holotypes.

The Balkans is a recognized biodiversity hotspot. Yet, for many parts of this region, knowledge about the diversity of many taxa is limited. This is particularly true for the spiders of Kosovo, for which increased efforts to elucidate the actual diversity have been started only recently. Here, based on traditional morphological analyses and DNA barcoding data, we present the first records of Nemesiidae Simon, 1889 from Kosovo, including the descriptions of Brachythele kosovarica Geci & Sherwood sp. nov. and Nemesia dukagjinica Geci & Sherwood sp. nov.

Temperature influences a variety of traits in ectotherms, including growth, metabolism, and behaviour and they have developed several strategies that includes behavioural and physiological adaptations to maintain their body function under varying thermal conditions. Mecicobothrium thorelli, a mygalomorph spider with small populations, low abundance, and winter activity, may be especially vulnerable to temperature changes, though this remains understudied. In this study, we aimed to assess the effect of different thermal ranges on prey capture behaviour and physiological traits on this species. The spiders were exposed to cold (5–10°C), medium (15–20°C), and warm temperatures (25–30°C), and we measure prey acceptance, prey detection latency, and prey attack speed by offering a prey and recording the behaviours using video. Additionally, spiders were acclimated to 5°C or 25°C for four weeks, and we measured the total content and composition of proteins and lipids. We found that M. thorelli accepted prey across all thermal ranges without distinction and demonstrated greatest ability to detect prey at moderated temperatures. Furthermore, the spiders were able to capture prey at all evaluated thermal ranges, but they exhibited a faster attack speed at warm temperatures. The content and composition of proteins and lipids did not show significant differences between low and high acclimation temperatures. Despite M. thorelli being more efficient at capturing prey at warm temperatures, medium and cold temperatures appear to be sufficient for feeding, and the spider is capable of maintaining similar levels of proteins and lipids at both low and warm temperatures. Those results are consistent with the winter temperatures at which this species carries out its main survival and reproduction activities.