We present here the results of the first semi-quantitative survey of arachnids conducted on coastal dunes of Spain. We used the optimized COBRA protocol to sample two localities along the Valencian coast. We collected 2886 specimens (58.2% juveniles), belonging to 78 species, 70 genera, 31 families, and 4 orders. The species Larinia chloris (Audouin, 1826) and the genus Cebrennus Simon, 1880 are reported in Europe for the first time. We further confirm the presence in Spain of the spiders Lathys narbonensis (Simon, 1876) and Ariadna inops Wunderlich, 2011. We present images of the diagnostic traits of the most interesting finds along with a checklist of the Arachnida present in the Valencian coastal dunes.

In the social behaviour of arthropods, regurgitation (feeding of the young) is a component of maternal care. In this paper, we describe regurgitation under laboratory conditions in species that share the same habitat, one subsocial (Anelosimus baeza) and a species considered to be solitary (Anelosimus nigrescens). The recently emerged spiderlings were fed by five of the nine A. baeza and six of the eight A. nigrescens females. In both species, the mother is critical in the initial stages, as spiderlings cannot feed themselves until the second instar. Our data suggest that A. nigrescens may be a subsocial species; this is the first report of regurgitation in these species. This fact shows the importance of regurgitation contributing to cooperation in live spiders. Future studies on maternal behaviour in these species are needed to elucidate the degree of sociality.

A new species in the mygalomorph trapdoor spider genus Nemesia, Nemesia bosmansi sp. nov., is described from central-western Italy. The spiders studied and described here were all collected in June 2002 by pitfall trapping in sandy dunes of the Parco Nationale del Circeo (Lazio). Additional information on the general state of Nemesia taxonomy is also provided.

In this contribution, Heterothele caudicula Simon, 1886 (Theraphosidae) is transferred to the genus Thalerommata Ausserer, 1875. Thalerommata caudicula new combination is based on the examination of the type that is characterized by flattened iridescent setae covering the abdomen, a synapomorphy of this genus. Thus, this is the ninth species of the genus known and Heterothele caudicula is removed from the Argentinean theraphosid fauna.

The evolution of the orb web was associated with a major radiation in spider diversity. Orb webs evolved for prey capture, and they also play important roles in courtship and mating. However, the construction and use of orb webs has associated costs, and the modification and loss of orb webs have evolved multiple times. While variation between species is evident, such as reductions or loss of the orb web for foraging, this kind of variation is rarely detailed within species. Here, I describe laboratory observations of foraging and mating without an orb web in a typical orb-weaving spider, the Australian garden orb weaver (hortophora biapicata). The behavioural range observed here shows the natural variation in these traits, on which selection might act to drive the reduction or loss of orb webs. Further investigation of these rare and unusual behaviours can help us understand the function and origin of important traits associated with the orb web, including both its construction and use, and how these traits can change over evolutionary time.

The spider genus Cybaeodes Simon, 1878 is found in the Western Mediterranean region. It belongs to the family Liocranidae, but its exact phylogenetic position has been debated due to its unique morphological features. Here we present the first records of the species Cybaeodes mallorcensis Wunderlich, 2008 outside of the Balearic Islands, specifically in the Iberian Peninsula, and speculate on the possible causes of this disjunct distribution. Additionally, we publish the first genetic data for the genus Cybaeodes and use them to interrogate about the phylogenetic position of this remarkable genus within the spider tree of life. The moderate genetic differentiation found among some of the individuals sampled in the Iberian Peninsula suggests that these may be native populations, and not the result of introductions from the Balearic Islands. However, sequencing specimens from the islands would help shed some light on their origin. Finally, the phylogenetic tree containing the new genetic data of Cybaeodes renders Liocranidae paraphyletic, the genus Cybaeodes being more closely related to the family Cithaeronidae and two liocranid genera, albeit with low supports. Our results highlight the need for a more comprehensive phylogeny to determine the placement of this obscure genus.

Three species of the cosmopolitan orb-weaving spider genus Tetragnatha Latreille, 1804 from India are redescribed, diagnosed, and illustrated. We provide detailed redescriptions, diagnoses, and illustrations of both sexes of Tetragnatha geniculata Karsch, 1892 and Tetragnatha lauta Yaginuma, 1959, and of the female of Tetragnatha serra Doleschall, 1857, the last two species being recorded from India for the first time. Additionally, Tetragnatha jaculator Tullgren, 1910 is also recorded for the first time from India, and Tetragnatha chamberlini (Gajbe, 2004) is proposed as a new junior synonym of Tetragnatha javana (Thorell, 1890). The current distributional records of these species from India are mapped.

Three new species of orb-weaver spider are described from Paraguay. Kaira mbywangiae sp. nov. has a remarkable complexity of abdominal humps and hump regions. Two species are described from the Humid Chaco flooded wetland region of Ñeembucú (Eustala davalosae sp. nov. and Kaira mbywangiae sp. nov.), and one from an Atlantic rainforest fragment in eastern Itapuá (Mangora sandovalae sp. nov.).

Four new species of Cymbiapophysa Gabriel & Sherwood, 2020 from north-western Ecuador are described based on unique combinations of male palpal bulb and female spermathecae morphology: C. ashily sp. nov., C. matildeae sp. nov., C. otongachi sp. nov., and C. yumbos sp. nov. An updated diagnosis, key to species, and comparative plate of the male palpal bulb of previously known species, with relabelling of some keels as necessary, and evidence of a subapical keel in Cymbiapophysa species, are presented. Additionally, we provide further commentaries about cymbial morphology and male palpal bulb structures, and two possible hypotheses related to the origin of accessory keels.

The mesovoid shallow substratum (MSS) of Gran Canaria is known to harbour a rich and diverse underground fauna. Since the 2000s, surveys have been intensified in this island and the number of species associated with caves and MSS has steadily increased, now exceeding fifty species. In this study, we describe another MSS species from Gran Canaria which is also the first eyeless member of the spider family Gnaphosidae from the Canary Islands. The new species is only tentatively placed in Poecilochroa Westring, 1874 and named P. exoculata sp. nov.

A new species of the jumping spider genus Indopadilla Caleb & Sankaran, 2019 is described from the Kanniyakumari district, Tamil Nadu state, India. Detailed diagnosis, description, and illustration are provided. In addition, a new locality record of Indopadilla darjeeling Caleb & Sankaran, 2019 is presented.

Sicarius rugosus (F. O. Pickard-Cambridge, 1899) is recorded for the first time in Honduras, with the record of three males and eight immatures collected in the town of Pespire, department of Choluteca, in the south of the country. We also recorded the species from the study of an exuvia collected in the department of Comayagua. A revised diagnosis, photographs of the males, distribution map, as well as information on the natural history of this species in Honduras, are provided.

Aquatic macrophytes provide foraging and refuge habitats for a wide variety of macroinvertebrates, including spiders. Examination of Salvinia auriculata plants in lagoons in southeastern Brazil resulted in 44 records of spiders belonging to seven families: Cheiracanthiidae, Linyphiidae, Lycosidae, Pisauridae, Salticidae, Tetragnathidae, and Theridiidae. At least seven morphospecies were identified. It is noteworthy that 61.3% of the sampled individuals were young spiders.

A new non-native species of the family Salticidae is described from Cornwall, United Kingdom: Anasaitis milesae sp. n. (♂♀). A brief discussion of the 17 non-native jumping spiders recorded as imported to the UK to date is provided.