The names Plexippus tectonicusPrószyński, 2003 and Plexippus similis Wesołowska & van Harten, 1994 are considered as junior synonyms of Plexippus clemens (O. Pickard-Cambridge, 1872). The male of Plexippus clemens (O. Pickard-Cambridge, 1872) is redescribed in detail, with a new distribution record from India. A detailed morphological description, diagnosis, and illustrations of the male reproductive organ are provided. A new distribution record of Plexippus clemens (O. Pickard-Cambridge, 1872) is also mapped.

We examined egg sac characteristics and oviposition sites of Metepeira calamuchita (Piel, 2001) (Araneidae) at two different habitat types, creosote bush scrub and Prosopis spp. forest patches, at the Ñacuñan Biosphere Reserve located in the Monte Desert of Mendoza, Argentina. At each site, we manually collected egg sacs of M. calamuchita between November and April. We recorded egg sac location, presence of detritus on the egg sac and its colouration. At scrub sites, there was a greater number of egg sacs anchored to the vegetation, while in forest sites most egg sacs were suspended by web threads. In addition, more egg sacs covered with detritus were found at scrub sites, but we did not find an association between egg sac colouration (brown/dark brown) and habitat type. Location of the egg sac and presence of detritus could function as defence strategies in environments with different pressures of egg sac predators and parasitoids.

The Mediterranean recluse spider Loxosceles rufescens (Dufour, 1820) is a public health concern due to its ability to inject venom that can cause skin lesions, referred to as loxoscelism. The spreading alarmism about recluse spiders which recently arose in Italy made it advisable to deepen knowledge about L. rufescens habitat preferences in human housing. Here, we report 14 confirmed cases of its occurrence in synanthropic habitats, and describe the housing characteristics. Our results pinpoint that traditional Italian houses of central Italy, in medieval towns and countryside, can be suitable for recluse spider colonization. The main features include the presence of walls of stone (with cracks and crevices), cellars, false ceilings, crawl spaces, wood materials (woodshed or wooden beams), and the occurrence of prey. Further characteristics which make conditions even more suitable are: large size, complex structure, and unoccupied premises. Due to its cryptic habits, even where L. rufescens is abundant, only the deployment of traps, following the recovery of a single or few individuals, revealed severe infestations. Our results confirm an unjustified negative notoriety of recluse spiders, considering that none of the inhabitants concerned, even if living in heavily infested housing, suffered from confirmed loxoscelism.

Two new species of the jumping spiders from Afghanistan (Jalalabad), Attulus nangraharsp. n. (♀) and Plexippus sengletisp. n. (♂♀), are diagnosed, illustrated, and described. Four species, Attulus ansobicus (Andreeva, 1976), Chalcoscirtus paraansobicusMarusik, 1990, Langona tartarica (Charitonov, 1946), and Pellenes epularis (O. Pickard-Cambridge, 1872), are reported for the salticid fauna of Afghanistan for the first time. A brief discussion of the state of knowledge of the Afghani Salticidae is provided.

Alopecosa longicymbiaSavelyeva, 1972, a poorly known species from east Kazakhstan, is redescribed and diagnosed based on the newly collected material. The species is known from a single taxonomic entry and only by the male. The original type series of this species has been lost. Alopecosa longicymbia is recorded from two nearby localities in east Kazakhstan. Digital photographs and B/W illustrations of the studied male and a map with collecting localities are provided.

The comb-footed spiders Coleosoma blandum O. Pickard-Cambridge, 1882 (male only) and C. floridanumBanks, 1900 (male only) are redescribed, based on newly collected material from Sri Lanka. The latter species is reported for the first time from the island.

A new species of CymbiapophysaGabriel & Sherwood, 2020, C. magnasp. nov. is described from Colombia. Proshapalopus marimbaiPerafán & Valencia-Cuéllar, 2018 is transferred to Cymbiapophysa from ProshapalopusMello-Leitão, 1923, based on male palpal bulb and tibial apophysis morphology, female spermathecal morphology, comparative labial cuspule counts in both sexes, and biogeography, creating the new combination Cymbiapophysa marimbaicomb. nov. Aspects of some structures of the male palpal bulb are also discussed.

The ischnocoline genus CatumiriGuadanucci, 2004 comprises four species distributed in Argentina, Brazil, Chile, and Uruguay. The type species Catumiri petropoliumGuadanucci, 2004 is known only from the male. We here provide a new diagnosis for Catumiri, describe the female of C. petropolium, and report new records of this species from Parque Nacional da Serra dos Órgãos, Reserva Biológica do Tinguá and Parque Nacional da Serra da Bocaina, Rio de Janeiro, Brazil. We also expand the distribution of Catumiri parvum (Keyserling, 1878) to Parque Nacional de Aparados da Serra, Praia Grande, Santa Catarina, Brazil, Alegrete, Rosário do Sul, Santana do Livramento, Pinheiro Machado, Bagé, and Jaguarão, all from Rio Grande do Sul, Brazil and Cerro de Los Cuervos, Lavalleja, Uruguay.

Epigeal spiders were collected in five lowland rainforest habitats of the Masako Reserve (Kisangani, RD Congo): primary forest (>200 y. old), old secondary forest (± 80 y.), young secondary forest (40 y.), old fallow (12 y.) and young fallow (5 y.). The density and spatial distribution of spider populations were estimated by means of nocturnal distance sampling performed in all habitats except young secondary forest, and by pitfall trapping, applied in all five habitats. The epigeal spiders of the Masako forest belong to 62 species in 25 families. The most frequent families are Ctenidae, Lycosidae, and Sparassidae in the distance samples, and Zodariidae, Salticidae, and Corinnidae in the pitfalls. The density of the Ctenidae increases in an ascending sequence from 0.007 ind. m^-2 in young fallow to 0.103 ind. m^-2 in primary forest. For Lycosidae the sequence is inversed. They are by far the most common in young fallow (0.028 ind. m^-2) and virtually absent in primary forest. Typical forest spiders, absent from open habitats, are common in old fallow which means that after 12 years, the typical forest fauna is already re-established. Only the young fallow fauna is clearly different from that of the other habitats, which confirms the high resilience and recolonization potential of epigeal spiders.

The female type of Cetonana aculifera (Strand, 1916), currently a nomen dubium in Trachelidae, is rediscovered, and the species is revalidated, based on a redescription of the female and first description of the male. The new genus Griswoldellagen. nov. is described to accommodate G. aculiferacomb. nov. as its type species, and is placed in Corinnidae: Castianeirinae. The relationships between the Madagascan Griswoldellagen. nov., DisnyssusRaven, 2015 from Australia, and CambalidaSimon, 1909 from the Afrotropics and Indian subcontinent, are discussed within a morphological and biogeographical context.

The salticid genus AvaruaMarples, 1955 is a junior homonym of the conoidean subgenus AvaruaBaker, 1938 (Gastropoda). The replacement name Avaruarachnenom. nov. is thus proposed for the preoccupied spider nomen.

A new species of Marma Simon, 1902, Marma pechichon sp. nov. is described. Marma nigritarsis (Simon, 1900) is recorded from Colombia for the first time. Diagnostic illustrations for M. pechichon sp. nov. and a distribution map showing records for Colombia are provided. Aspects of secondary spermathecae and accessory glands of Euophryini are briefly discussed.

A collection of amaurobiid spiders from the Western Mediterranean region is analysed. Callobius theoblickisp. n. is newly described from north Portugal. Amaurobius barbarus Simon, 1911, from Algeria and Spain, and A. cerberusFage, 1931, from the south of Spain, are redescribed or newly illustrated. Amaurobius erberi is recorded for the first time in Algeria. Amaurobius minorcaBarrientos & Febrer, 2018, until now only known from Menorca, is cited also in Majorca and in continental Spain.

Most lines in the sheets of four linyphiid species bore numerous small droplets. Droplet-bearing lines of Linyphia simplicata (F. O. Pickard-Cambridge, 1902) and Neriene coosa (Gertsch, 1951) adhered weakly to smooth, dry surfaces, contradicting previous statements that such lines in linyphiid webs are not sticky. Droplets at the intersections of lines tended to be larger than nearby droplets on the same lines, and were more widely separated from adjacent droplets than were other, nearby droplets on the same lines. A self-assembly hypothesis to explain these findings, that larger droplets accumulated at intersections as a result of lines in the sheet scraping against each other, was supported by confirming that larger intersection droplets were more widely separated from adjacent droplets than were smaller intersection droplets. These observations suggest a new, dynamic view of linyphiid sheet webs, in which the distribution of sticky material is adjusted advantageously immediately after lines are produced, due to the upward dabbing movements of the spider's abdomen that press the sheet lines against each other during sheet construction, and perhaps also to other movements of newly laid lines against each other. Larger droplets maybe advantageous in binding lines together, and in adhering to prey.

The genera LasiodoridesSchmidt & Bischoff, 1997 and Thrixopelma Schmidt, 1994 are preliminarily revised, and their taxonomy stabilized. Both sexes of Lasiodorides polycuspulatusSchmidt & Bischoff, 1997, and the male of Lasiodorides striatus (Schmidt & Antonelli, 1996) are redescribed, and the genus Lasiodorides is rediagnosed. Lasiodorides rolinaeTesmoingt, 1999 is proposed as a junior synonym of L. polycuspulatussyn. nov., based on colouration and spermathecal morphology. Lasiodorides remotus Schmidt, 2007 is proposed as a junior synonym of L. polycuspulatussyn. nov., based on spermathecal morphology. Thrixopelma aymara (Chamberlin, 1916) and Thrixopelma lagunasSchmidt & Rudloff, 2010 are redescribed. Thrixopelma ockerti Schmidt, 1994 is illustrated from the syntype series and redescribed based on a non-type female from Iquitos, Peru, held in the collections of the Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru. Thrixopelma longicolli (Schmidt, 2003) comb. nov. is newly transferred from Lasiodorides to Thrixopelma based on palpal bulb morphology, and the holotype male is redescribed. The inherent problems of the paratype exuviae of this taxon are also discussed. Thrixopelma peruvianum (Schmidt, 2007) comb. nov. is newly transferred from EuathlusAusserer, 1875 following examination of the holotype female exuvia and a conspecific non-type female exuvia. Thrixopelma cyaneolum Schmidt, Friebolin & Friebolin, 2005 is discussed ad illustrated from the syntype female exuviae. Thrixopelma pruriensSchmidt, 1998 is discussed and illustrated from the holotype female exuvia, and the problematic non-type material discussed. Finally, we argue that future designation of exuviae as type specimens of novel theraphosid spiders should be considered an unacceptable practice in arachnology.

Most orb weavers orient downward on their orbs, but here we describe an unusual pattern of orientation in the tetragnathid Azilia guatemalensis. This species changes its orientation on the hub with a consistent day/night pattern. During the day, the spiders orient upward on the orb, but orient downward during the night. In addition, we found that the spiders construct a few silk lines that connect the hub with a sparse mesh near the upper edge of the orb which, in turn, is connected to the substrate. When disturbed, the spider runs using these lines and hides on the substrate, suggesting that its upward orientation during the day, and its escape behaviour, may be a response to diurnal enemies.

Knowledge on spiders in Paraguay is abysmal, even in Salticidae, the most diverse spider family. Prior to this study, 40 species were registered for Paraguay, which may be underestimating the true species diversity in the country by five times or more. This study provides a first baseline for jumping spiders in Paraguay from evaluation of three salticid collections. We provide 32 new country records (a remarkable 76% of the total number of species included in the study) including the description of a new species of PachomiusPeckham & Peckham, 1896, Pachomius rubrogastrussp. nov., from Paraguay and Argentina. Thus, the salticid fauna of Paraguay is raised from 40 species to 72. We provide images of 21 new records, and diagnose and illustrate the new species of Pachomius. Through this publication, we have begun to fill in the immense knowledge gap of the spider fauna of Paraguay. We also provide brief directions to further Salticidae knowledge in Paraguay.

This is the second part of a systematic analysis of the Lycosidae collection of Walter Wittmer from Bhutan, dealing with 16 species from subfamilies Lycosinae (Lycosa and Ovia), Pardosinae (Draposa, Wadicosa, and the Pardosa species-groups nebulosa, paludicola, sutherlandi, taczanowskii, and wagleri) and Hippasinae (Hippasa). Ovia emae sp. nov. is newly described. Descriptions of the yet unknown female of Ovia alboannulata (Yin, Peng, Xie, Bao & Wang, 1997) and the male of Pardosa mukundiTikader & Malhotra, 1980 are provided. All species are illustrated and their affinities are discussed.

Spiders can modify their web construction behaviour according to environmental conditions. Here, we examined how the web structure of Tetragnatha tenuissima differentiates depending on habitat type (swamp or river edge) at La Selva Biological Station, Costa Rica. We characterized the web architecture based on length, number of radii, and the spiral spacing relative to web length. There were no significant differences on the length or number of radii between the webs present in the swamp and river habitats. In terms of the spiral spacing relative to web length, there was a significant difference between habitats, with less distance in river-side webs than in the ones on swamps. This could be explained by the potential differential resource availability on each environment. Therefore, habitat type appears as an explanatory variable for differences on the web structure of T. tenuissima. Due to the small number of identifiable individuals of other Tetragnatha species, the effect of congeneric species co-occurrence on web structure remains as a factor to be tested in future research.

Two new species of theridiid spiders are described from northern Iran: Episinus mikhailovisp. n. (♂♀, Gilan and Mazandaran provinces) and Theridion arsiasp. n. (♀, Qazvin Province); the latter has a unique type of thread-like mating plug previously undocumented in the family. Furthermore, Enoplognatha submargaritaYaginuma & Zhu, 1992, stat. reval. is rediagnosed and removed from the synonymy of Enoplognatha margarita Yaginuma, 1964, and a unique line of fine perforations connecting the copulatory openings are newly documented for this species. Finally, the first records of E. margarita from Mongolia and E. submargarita from Kyrgyzstan are also presented.