Spatial distribution and faunal composition of millipedes of the family Spirostreptidae Brandt, 1833 in the Brazilian Atlantic Forest (Diplopoda, Juliformia, Spirostreptida).

The Atlantic Forest is known for its richness and diversity of species. Nonetheless, the diversity of millipedes in the biome is still poorly known. In this work, the distribution and the faunal composition of millipedes of the family Spirostreptidae Brandt, 1833 (order Spirostreptida) from the Atlantic Forest are provided. A total of 159 occurrence points were compiled, and 59 species in 17 genera were listed. Gymnostreptus Brölemann, 1902 was recovered as the richest genus in the Atlantic Forest with 14 species and one subspecies. The species Plusioporus setiger (Brölemann, 1902) presented the highest number of records, with 22 occurrence points in at least 20 municipalities. A total of 35 species were recorded from only one municipality. Considering all the threats on the biome, this paper is important for our understanding of the Brazilian millipede fauna and can be useful to determine places that require valuations for collecting efforts and conservation policies.

Temperature and productivity distinctly affect the species richness of ectothermic and endothermic multitrophic guilds along a tropical elevational gradient.

The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.

Spider species richness and sampling effort at Cracraft´S Belém Area of Endemism.

A list of spider species is presented for the Belém Area of Endemism, the most threatened region in the Amazon Basin, comprising portions of eastern State of Pará and western State of Maranhão, Brazil. The data are based both on records from the taxonomic and biodiversity survey literature and on scientific collection databases. A total of 319 identified species were recorded, with 318 occurring in Pará and only 22 in Maranhão. About 80% of species are recorded at the vicinities of the city of Belém, indicating that sampling effort have been strongly biased. To identify potentially high-diversity areas, discounting the effect of variations in sampling effort, the residues of a linear regression between the number of records and number of species mapped in each 0.25°grid cells were analyzed. One grid, representing the Alto Turiaçu Indigenous land, had the highest deviation from the expected from the linear regression, indicating high expected species richness. Several other grid cells showed intermediate values of the regression residuals, indicating species richness moderately above to the expected from the model.

A taxonomic revision of the Neotropical spider genus Xiruana Brescovit 1997 (Araneae: Anyphaenidae, Anyphaeninae).

The genus Xiruana Brescovit, 1997 is currently composed of four South American species: X. gracilipes (Keyserling) from Brazil, Bolivia and Argentina, X. affinis (Mello-Leitão) from Brazil, X. hirsuta (Mello-Leitão) from Venezuela, Brazil, Paraguay, Argentina and Uruguay, and X. tetraseta (Mello-Leitão) from Venezuela, Brazil and Paraguay. Of these, the last three are redescribed in this paper, including the first description of the females of X. hirsuta and X. tetraseta. Additionally, we describe thirteen new species: Xiruana pocone n. sp. from Brazil, Paraguay and Argentina; X. bifida n. sp. from Brazil and Paraguay; X. aymara n. sp. from Bolivia; X. cocha n. sp. from Peru; X. fiebrigi n. sp. from Paraguay, and X. ajuricaba n. sp., X. tribarrense n. sp., X. guaia n. sp., X. jaboticabal n. sp., X. minacu n. sp., X. tapirape n. sp., X. lusitania n. sp., X. silarae n. sp., all endemic to Brazil. The known geographical distribution of all species here presented is mapped.

Two new species of the Neotropical spider genus Umuara Brescovit (Araneae, Anyphaenidae, Anyphaeninae) from Brazil.

Two new species of the genus Umuara are described from Brazil: Umuara freddyi, from the states of Bahia, Minas Gerais and São Paulo and Umuara xingo, from the states of Ceará, Paraíba, Sergipe, Bahia, Espírito Santo, and Rio de Janeiro.

Four new caponiids species (Araneae, Caponiidae) from the West Indies and redescription of Nops blandus (Bryant).

We update the knowledge of the unusual Caponiidae spiders from the West Indies with the description of four new species, and the redescription of Nops blandus (Bryant) including the first description of the female. Specimens previously assigned to N. blandus from Hispaniola and Puerto Rico represents two new species: Nops hispaniola n. sp. and Nops agnarssoni n. sp. respectively; while the distribution of the former is limited to British and U. S. Virgin Islands. The others two new species are Nops finisfurvus n. sp. from British Virgin Islands and Cubanops luquillo n. sp. from Puerto Rico. Female internal genitalia of Nops species are described, photographed and illustrated for the first time.

On the spider genus Thymoites in the Neotropical Region (Araneae, Theridiidae): nine new species, complementary descriptions and new records.

The theridiid genus Thymoites Keyserling, 1884 is distributed worldwide. Spiders of this genus are mainly known from the Neotropical Region, but are poorly studied in Brazil. In this paper nine new species of Thymoites are described from Brazil, one from the state of Alagoas: Thymoites murici n. sp.; two from São Paulo: T. bocaina n. sp., T. ilhabela n. sp. and T. taiobeiras n. sp. from states of Minas Gerais and São Paulo; one from the state of Santa Catarina: Thymoites tabuleiro n. sp.; and, three from state of Rio Grande do Sul: Thymoites cristal n. sp., T. camaqua n. sp. and T. piratini n. sp., all based on males and females; and one from the state of Rio de Janeiro: T. pinheiral n. sp. based on male. The male of Thymoites puer (Mello-Leitão, 1941) and the female of T. melloleitaoni (Bristowe, 1938) are here described and illustrated for the first time. Additionally, new records from Brazil are provided for Thymoites ilvan Levi, 1964 for state of Santa Catarina; T. iritus Levi, 1964 for state of Goiás; T. piarco (Levi, 1959) for state of Amazonas; and, T. struthio (Simon, 1895) for Bolivia.

Strong spatial structure, Pliocene diversification and cryptic diversity in the Neotropical dry forest spider Sicarius cariri.

The Brazilian Caatinga is part of the seasonally dry tropical forests, a vegetation type disjunctly distributed throughout the Neotropics. It has been suggested that during Pleistocene glacial periods, these dry forests had a continuous distribution, so that these climatic shifts may have acted as important driving forces of the Caatinga biota diversification. To address how these events affected the distribution of a dry forest species, we chose Sicarius cariri, a spider endemic to the Caatinga, as a model. We studied the phylogeography of one mitochondrial and one nuclear gene and reconstructed the paleodistribution of the species using modelling algorithms. We found two allopatric and deeply divergent clades within S. cariri, suggesting that this species as currently recognized might consist of more than one independently evolving lineage. Sicarius cariri populations are highly structured, with low haplotype sharing among localities, high fixation index and isolation by distance. Models of paleodistribution, Bayesian reconstructions and coalescent simulations suggest that this species experienced a reduction in its population size during glacial periods, rather than the expansion expected by previous hypotheses on the paleodistribution of dry forest taxa. In addition to that, major splits of intraspecific lineages of S. cariri took place in the Pliocene. Taken together, these results indicate S. cariri has a complex diversification history dating back to the Tertiary, suggesting the history of dry forest taxa may be significantly older than previously thought.

Revision of Neotropical wolf spider genus Arctosa C.L. Koch, 1847 (Araneae: Lycosidae), with description of seven new species.

The genus Arctosa C.L. Koch is redescribed and diagnosed. Seven new species are described, four of them based on both sexes (A. conflicta sp. nov., A. costenola sp. nov., A. jibarosa sp. nov. and A. villa sp. nov.), two only on females (A. ayaymama sp. nov. and A. mineira sp. nov.), and one only on the male (A. pacaya sp. nov.). We also propose the transference of Arctosa humicola (Bertkau, 1880) and Arctosa fusca (Keyserling, 1877) to Trochosa C.L. Koch, 1847, and the new synonymy of Arctosa inconspicua (Bryant, 1948) with Trochosa humicola (Bertkau, 1880) comb. nov. Besides, Arctosa andina (Chamberlin, 1916) and Arctosa pugil (Bertkau, 1880) are transferred to Hogna Simon, 1885, and Arctosa aussereri (Keyserling, 1877) to Prolycosides Mello-Leito, 1942. Additionally, eight lycosid species are synonymized with Prolycosides aussereri: Schizocosa proletaria (Tullgren, 1905); Arctosa workmani (Strand, 1909); Hogna planithoracis (Mello-Leito, 1938); Hogna variolosa (Mello-Leito, 1941); Megarctosa melanostoma (Mello-Leito, 1941); Hippasosa huachoi (Mello-Leito, 1942); Pirata abalosi (Mello-Leito, 1942); and Pirata soukupi (Mello-Leito, 1942). We also transfer Trochosa tenebrosa Keyserling, 1877 to Arctosa. The males of Arctosa tenebrosa (Keyserling, 1877) comb. nov. and Trochosa humicola (Bertkau, 1880) comb. nov. are described for the first time.

The tiniest violin: the male of Loxoscelesvallenar (Araneae, Sicariidae).

In recent years, several endemic species of Loxosceles, violin spiders, have been described from the North-Central Chile biodiversity hotspot, some of which have ambiguous placement within the species groups of the genus. In a recent expedition to the Atacama region, we collected male specimens representing new records of two recently described species: Loxoscelesvicentei Taucare-Ríos, Brescovit & Villablanca, 2022 and Loxoscelesvallenar Brescovit, Taucare-Ríos, Magalhaes & Santos, 2017 (Araneae, Sicariidae). Males of the latter are hitherto unknown and are here described for the first time. Examination of the morphology of these species revealed characters such as an embolic keel and digitiform median receptacles, which suggest they do not belong in the laeta species group, but rather in the spadicea species group, which is briefly re-diagnosed. With carapace lengths smaller than 2 mm, the newly discovered males of L.vallenar are the tiniest members of the genus. In addition, males of this species bear strong macrosetae in the clypeus, a sexually dimorphic character not previously reported in Loxosceles.

Taxonomic revision of the jumping spider genus Tullgrenella Mello-Leito, 1941 (Araneae: Salticidae: Freyina).

This paper presents a taxonomic revision of the genus Tullgrenella Mello-Leito, 1941. Four new species are described: Tullgrenella aisenbergae Marta, sp. nov. (Brazil) (), T. legalissima Marta & Hagopin sp. nov. (Uruguay) (), T. galianoae Marta, sp. nov. (Brazil) () and T. sciosciae Marta & Bustamante sp. nov. (Brazil) (). The males of T. corrugata Galiano, 1981 and T. peniaflorensis Galiano, 1970, and the female of T. selenita Galiano, 1970 are described for the first time. An updated diagnosis for the genus is provided based on the detailed comparative morphological studies. In addition, we present a proposal and discussion about the species groups of Tullgrenella based on the putative synapomorphies as well as the updated distribution of the genus in South America.

The first species of the genus Caponina from Brazilian Amazonia (Araneae: Caponiidae).

The genus Caponina Simon, 1891 comprises eleven species of medium-sized, soil-dwelling caponiids. Most members of Caponina have six eyes, but some have five, four, three or two eyes (Brignoli 1977, Platnick 1994). The genus is widespread in South and Central America (Platnick 2012). To date, only three species have been recorded from Brazil: Caponina alegre Platnick, 1994 from the state of Rio Grande do Sul, C. notabilis (Mello-Leitão, 1939) from the states of Paraná and Rio Grande do Sul, and C. tijuca Platnick, 1994 from the state of Rio de Janeiro (Platnick 1994). In this paper we describe a new species from the state of Pará, in Brazilian Amazonia. Caponina papamanga new species was collected during the "Butantan na Amazonia" project, founded by the Instituto Butantan. The phylogenetic relationships of C. papamanga could not be studied, but the greatly elongated embolus, the dorsal tubercle on the palpal femur (Figs. 7, 9) and the massive epigynal sclerotizations (Fig. 10) suggest that this species belongs to the monophyletic Andean group proposed by Platnick (1994: 7). All morphological observations and illustrations were made using a Leica MZ12 stereomicroscope with camera lucida. The epigynum was dissected and immersed in clove oil for visualization of internal structures following Levi (1965). Descriptions and measurements follow Platnick (1994). Measurements are given in millimeters. Scanning electron microscope (SEM) images were taken using a Jeol-JSM-5200 with attached SLR digital camera. The material examined was deposited in the collections of the Instituto Butantan, Sgo Paulo (IBSP, curator: D.M. Barros Battesti) and the Museu Paraense Emílio Goeldi, Belém (MPEG, curator: A.B. Bonaldo).

New species of the neotropical spider genus Celaetycheus Simon, 1897 (Araneae: Ctenidae).

Nine species of the Neotropical spider genus Celaetycheus Simon, 1897 are newly described. All the species are endemic to the State of Bahia, northeast of Brazil: Celaetycheus abara sp. nov., C. aberen sp. nov., C. acaraje sp. nov., C. beiju sp. nov., C. bobo sp. nov., C. caruru sp. nov., C. moqueca sp. nov., C. mungunza sp. nov. and C. vatapa sp. nov. A new generic diagnosis, species diagnoses and distributional maps are provided.

New species of the spider genus Exocora Millidge, 1991 (Araneae: Linyphiidae) from Brazil.

The genus Exocora Millidge, 1991 is recorded from Brazil for the first time. Six new species herein are described and illustrated, all presenting male and female, from Atlantic Forest area. Exocora phoenix n. sp. is recorded in the states of Minas Gerais, Espírito Santo, São Paulo, Rio de Janeiro, Paraná and Santa Catarina, E. girotii n. sp. in the states of São Paulo, Rio de Janeiro, Paraná and Santa Catarina, E. ribeiroi n. sp. in São Paulo, Santa Catarina and Rio Grande do Sul, E. medonho n. sp. in Rio de Janeiro, E. nogueirai n. sp. in São Paulo and E. una n. sp. in Bahia.

The genus Loxosceles Heineken & Lowe (Araneae: Sicariidae) in Cuba and Hispaniola, West Indies.

The three known species of the genus Loxosceles Heineken & Lowe from Cuba and Hispaniola are revised and two new species, Loxosceles maisi sp. nov. and Loxosceles mogote sp. nov., are described from the eastern region of Cuba. These new species are included in the reclusa group, and are considered close to Loxosceles taino Gertsch & Ennik as they have a greatly thickened male palpal tibia, a projecting cymbium, and large receptacles in the female genitalia. The distribution ranges of the known Cuban and Hispaniolan species are extended.

The spider genus Kukulcania in South America (Araneae: Filistatidae): a redescription of K. brevipes (Keyserling) and new records of K. hibernalis (Hentz).

Two species of the spider genus Kukulcania are known from South America. Kukulcania brevipes (Keyserling), originally described from Peru, is here diagnosed, illustrated and redescribed, with several new records provided for eastern Peru and northern Chile. The synanthropic Kukulcania hibernalis (Hentz) is illustrated and diagnosed, with several new records extending the distribution of this species from northern Venezuela to southern Brazil.

Revision of Breda and proposal of a new genus (Araneae: Salticidae).

The genus Breda Peckham & Peckham, 1894 is revised and nine valid species are redescribed and illustrated. The monotypic Paradescanso Vellard, 1924 is established as a new junior synonym of the genus. Breda modesta (Taczanowski, 1878) comb. nov. is transferred from Balmaceda Peckham & Peckham. The following synonymies are also established: Paradescansofallax Vellard, 1924 = Breda apicalis Simon, 1901 syn. nov.; B. quinquedentata Badcock, 1932 = B. apicalis Simon, 1901 syn. nov.; B. leucoprocta Mello-Leitão, 1940 = B. modesta (Taczanowski, 1878) syn. nov.; B. spinimanu (Mello-Leitão, 1941) = B. modesta (Taczanowski, 1878) syn. nov. The females of B. bicruciata (Mello-Leitão, 1943) and B. bistriata (C.L. Koch, 1846) are described and illustrated for the first time, as well as the male of B. lubomirskii (Taczanowski, 1878). Both sexes of Breda akypueruna sp. nov. and males of B. nanica sp. nov. and B. paraensis sp. nov., all three from the Amazon, are described and illustrated, increasing the present member list up to 13 species. Druzia gen. nov. is proposed to include B.flavostriata Simon, 1901. The Australian "Breda" jovialis (L. Koch, 1879) is tentatively transferred to Ocrisiona Simon.

Description of the female of Aysha yacupoi Brescovit 1992 (Araneae: Anyphaenidae).

The female of Aysha yacupoi Brescovit, 1992 is described and illustrated for the first time. Males and female specimens were observed together in the same plants. Some data on natural history are presented.

The six-eyed sand spiders of the genus Sicarius (Araneae: Haplogynae: Sicariidae) from the Brazilian Caatinga.

In this paper we revise the species of Sicarius (Araneae: Sicariidae) from the Brazilian Caatinga, the largest tropical dry forest nucleus in the world. We redescribe, designate a neotype and provide new records for Sicarius tropicus (Mello- Leitão, 1936), the only species previously known from the region, and describe three new species: S. cariri n. sp., S. diadorim n. sp. and S. ornatus n. sp. We report high intraspecific variation in the genitalic morphology of these species, especially in females. We also provide anecdotal observations on natural history and behavior of these species, including diet, mating behavior and clutch size. We include an identification key for Brazilian Caatinga species of Sicarius.

Contributions to the taxonomy and distribution of the genus Mesabolivar in southern South America (Araneae: Pholcidae).

Two new species of Mesabolivar González-Sponga are described, M. charrua sp. nov. and M. uruguayensis sp. nov. The male of Mesabolivar tandilicus Mello-Leitão is redescribed. Notes on the natural history of the studied species are presented.