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The Loxosceles genus belongs to the Sicariidae family and it comprises species whose venom can cause accidents with potentially fatal consequences. We have previously shown that SMase D is the enzyme responsible for the main pathological effects of Loxosceles venom. Despite the severity of accidents with Loxosceles , few species are considered to be of medical importance. Little is known about the venom of non-synanthropic species that live in natural environments. To contribute to a better understanding about the venom's toxicity of Loxosceles genus, the aim of this study was to (i) characterize the toxic properties of Loxosceles amazonica from two different localities and a recent described cave species Loxosceles willianilsoni and (ii) compare these venoms with that from Loxosceles laeta, which is among the most toxic ones. We show here that both L. amazonica venoms (from the two studied locations) and L. willianilsoni presented SMase D activity similar to that exhibited by L. laeta venom. Although L. amazonica and L. willianilsoni venoms were able to induce complement dependent human erythrocytes lysis, they were not able to induce cell death of human keratinocytes, as promoted by L. laeta venom, in the concentrations tested. These results indicate that other species of Loxosceles , in addition to those classified as medically important, have toxic potential to cause accidents in humans, despite interspecific variations that denote possible less toxicity. • Loxosceles spider venoms may cause accidents with potentially fatal consequences. • Despite the severity of accidents, few species are considered of medical importance. • Venom from the cave species , L. willianilsoni, induce complement dependent hemolysis. • L. willianilsoni and L. amazonica venoms do not induce keratinocyte death as L. laeta. • Loxosceles venoms present interspecific variations in their toxicity. [ABSTRACT FROM AUTHOR]

The genus Typhochlaena C.L. Koch, 1850 consists of five small size arboreal tarantula species with remarkable colored abdominal patterns and a very restricted geographic range in Brazil. Here, we describe the male of Typhochlaena curumim Bertani, 2012, which was collected in an area of Brazilian Atlantic Rainforest. The new record extends the northern limit of the geographic range for both the genus and species. As Typhochlaena spp. are now especially popular and requested in the pet market, and because T. curumim is classified as Critically Endangered, we discuss the impacts of the international trade and other challenges on conservation of the genus. [ABSTRACT FROM AUTHOR]

The genus Loxosceles Heinecken & Lowe, 1832 has 91 representatives in the New World. Despite medical relevancy, the taxonomy of the genus is poorly understood. South American Loxosceles were divided into four groups of species: laeta, spadicea, gaucho and amazonica; this last one has a single species, Loxosceles amazonica Gertsch, 1967. More recently, the natural occurrence of L. amazonica in the New World has been questioned, due to the strong morphological resemblance and close phylogenetic relationship with Old World species, mainly with Loxosceles rufescens (Dufour, 1820). Herein, L. amazonica is rediagnosed and its morphological variation and natural distribution discussed. Two new species closely related to it from northeastern Brazil are also described, Loxosceles willianilsoni sp. n., from the state of Rio Grande do Norte, and Loxosceles muriciensis sp. n., from the state of Alagoas. The relationships of these new species with L. amazonica and L. rufescens are discussed. [ABSTRACT FROM AUTHOR]

The spider family Sicariidae includes three genera, Hexophthalma, Sicarius and Loxosceles. The three genera share a common characteristic in their venoms: the presence of Sphingomyelinases D (SMase D). SMases D are considered the toxins that cause the main pathological effects of the Loxosceles venom, that is, those responsible for the development of loxoscelism. Some studies have shown that Sicarius spiders have less or undetectable SMase D activity in their venoms, when compared to Hexophthalma. In contrast, our group has shown that Sicarius ornatus, a Brazilian species, has active SMase D and toxic potential to envenomation. However, few species of Sicarius have been characterized for their toxic potential. In order to contribute to a better understanding about the toxicity of Sicarius venoms, the aim of this study was to characterize the toxic properties of male and female venoms from Sicarius tropicus and compare them with that from Loxosceles laeta, one of the most toxic Loxosceles venoms. We show here that S. tropicus venom presents active SMases D. However, regarding hemolysis development, it seems that these toxins in this species present different molecular mechanisms of action than that described for Loxosceles venoms, whereas it is similar to those present in bacteria containing SMase D. Besides, our results also suggest that, in addition to the interspecific differences, intraspecific variations in the venoms' composition may play a role in the toxic potential of venoms from Sicarius species. [ABSTRACT FROM AUTHOR]

Legal and illegal wildlife trade is a multibillion dollar industry that is driving several species toward extinction. Even though wildlife trade permeates the Tree of Life, most analyses to date focused on the trade of a small selection of charismatic vertebrate species. Given that vertebrate taxa represent only 3% of described species, this is a significant bias that prevents the development of comprehensive conservation strategies. In this short contribution, we discuss the significance of global wildlife trade considering the full diversity of organisms for which data are available in the IUCN database. We emphasize the importance of being fast and effective in filling the knowledge gaps about non-vertebrate life forms, in order to achieve an in-depth understanding of global trading patterns across the full canopy of the Tree of Life, and not just its most appealing twig. • Global wildlife trade is a multibillion dollar industry that is driving several species toward extinction. • Most analyses on global wildlife trade are biased toward vertebrates. • Multiple datasets suggest that a huge fraction of illegal and legal traded wildlife is plant and invertebrates. • It is fundamental to fill this knowledge gap about global trade of non-vertebrate life forms. [ABSTRACT FROM AUTHOR]

Guyruita Guadanucci et al., 2007 is an ischnocoline genus with three described species from Brazil and Venezuela. Two new Brazilian species from the states of Rio Grande do Norte (Guyruita isae n. sp.) and Espírito Santo (Guyruita giupponii n. sp.) are described. A key is provided for identification of Guyruita species. Map with records and information on species habitat are also given.

Spiders of the islands on the coast of the state of São Paulo, Brazil are poorly known. Herein, we redescribe and discuss the taxonomic position of Psalistops crassimanus Mello-Leitão, 1923, described from Alcatrazes Island and formerly included in the Barychelidae. This species is, herein, transferred to the genus Stenoterommata Holmberg, 1881, Nemesiidae, and the new combination Stenoterommata crassimana (Mello-Leitão, 1923) n. comb. is established. Stenoterommata crassimana males are diagnosed by the very slender and long apical portion of embolus having a strong curvature close to its apex. The females have the spermathecae with single elongate lobe bearing two receptacles. This species is probably endemic to the Alcatrazes Archipelago and Queimada Grande and Queimada Pequena Islands, on the coast of the state of São Paulo, Brazil.