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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. [ABSTRACT FROM AUTHOR]

Four new species of the spider genus Ochyrocera Fage, 1912 are described from iron caves in the state of Minas Gerais, Brazil. Here we present the third anophtalmic and depigmented species of the genus, O. dorinha sp. nov., and three other depigmented species: O. monica sp. nov., O. magali sp. nov. and O. rosinha sp. nov. Only O. dorinha sp. nov. and O. rosinha sp. nov. are considered as troglobites due the ocular reduction or anophthalmia and elongated appendages, two troglomorphic features absent in the other species described. [ABSTRACT FROM AUTHOR]

Epipompilus Kohl comprises 52 species of wasps that are parasitoids of spiders; 16 species occur in the Neotropical region and 36 species occur in the Australian region. The biological knowledge of this genus is limited and its interactions and host spiders are still incipient. Here, we report some behavioural and biological characteristics of E. excelsus, a parasitoid of the tube-dwelling spider Ariadna mollis. We observed an E. excelsus female attacking an adult female of A. mollis in São Paulo, Brazil. We photographed daily the larval development of the wasp, from the egg stage to adult emergence. The entire developmental cycle of the wasp took 24 days. This period was shorter than the developmental periods of wasps belonging to other genera of Pompilidae. Although all species within Pompilidae use spiders as host, they present great behavioural diversity, characterized by different ethological sequences. In conclusion, this study demonstrated that the Neotropical species of Epipompilus exhibit biological characteristics similar to the Australian species, acting as a koinobiont ectoparasitoid, but displays differences in larval morphology. Studies on other species could elucidate the extent of these differences and similarities, contributing to our understanding of the evolutionary history of Epipompilus, and consequently of Pompilidae. [ABSTRACT FROM AUTHOR]

The present study aimed to cytogenetically analyse five Ctenidae species Ctenus ornatus (Keyserling, 1877), Ctenus medius (Keyserling, 1891), Phoneutria nigriventer (Keyserling, 1891), Viracucha andicola (Simon, 1906), and Enoploctenus cyclothorax (Philip Bertkau, 1880), from Brazil. All species presented a 2n♂ = 28 except for V. andicola, which showed 2n♂ = 29. Analysis of segregation and behavior of sex chromosomes during male meiosis showed a sex chromosome system of the type X1X20 in species with 28 chromosomes and X1X2X30 in V. andicola. C banding stained with fluorochromes CMA3 and DAPI revealed two distributions patterns of GC-rich heterochromatin: (i) in terminal regions of most chromosomes, as presented in C. medius, P. nigriventer, E. cyclothorax and V. andicola and (ii) in interstitial regions of most chromosomes, in addition to terminal regions, as observed for C. ornatus. The population of Ubatuba (Sao Paulo State) of this same species displayed an additional accumulation of GC-rich heterochromatin in one bivalent. Fluorescent in situ hybridization revealed that this bivalent corresponded to the NOR-bearing chromosome pair. All analyzed species have one bivalent with 18S rDNA site, except P. nigriventer, which has three bivalents with 18S rDNA site. Karyotypes of two species, C. medius and E. cyclothorax, are described for the first time. The latter species is the first karyotyped representative of the subfamily Acantheinae. Finally, 18S rDNA probe is used for the first time in Ctenidae at the present study. [ABSTRACT FROM AUTHOR]

The class Diplopoda corresponds to about 12,000 nominal species. The species are associated with almost all soil strata, efficiently contributing to nutrient cycling. Some species are considered agricultural pests, widely introduced through human activities. In Brazil, 12 introduced species are known, with most of them originating from Asia, and spread mainly in the Southeast region. Among these, stand out Oxidus gracilis (C.L. Koch) and Orthomorpha coarctata (Saussure) (Polydesmida, Paradoxosomatidae), recorded for almost all regions of the country, and Trigoniulus corallinus (Gervais) (Spirobolida, Pachybolidae), occurring in the North, Northeast, and Southeast regions. However, even though these species are widely distributed, none of them has been registered so far in the state of Maranhão. In this perspective, the present work aims to register for the first time in Maranhão the occurrence of these species from samplings in urban areas from the municipality of Códo, eastern region of the state, during the months of January and February of 2023. The individuals have been found buried in more superficial layers of the soil or associated with nearby pools of water in the litter. It is important to highlight that the region has great vegetation diversity, but without any conservation unit formulated so far, in addition to currently suffering from the advance of Silviculture and extractive activities, which may lead to the loss of biological diversity in areas still almost unexplored in relation to fauna. [ABSTRACT FROM AUTHOR]

Gelanor Thorell, 1969 comprises 11 Neotropical species. In this paper, two new species are described from Bra- zil: Gelanor hoga sp. nov., based on males and females from the state of Amazonas, and Gelanor cachimbo sp. nov., based on males from the state of Pará. Additionally, new records from Brazil are provided for Gelanor altithorax Keyserling, 1893, Gelanor consequus O. P.-Cambridge, 1902, Gelanor juruti Benavides & Hormiga, 2016, Gelanor latus (Keyserling, 1881), Gelanor waorani Benavides & Hormiga, 2016 and Gelanor zonatus (C.L. Koch, 1845) and a key to the Brazilian species and illustrations are provided. [ABSTRACT FROM AUTHOR]

The Araneidae is among the most speciose spider families, but there are few karyotype studies (1.9%) and some species-rich clades are without any chromosomal study. Understanding the evolution of chromosome number and Sex Chromosome Systems is made more difficult by many uncertain evolutionary relationships within the family. In this work, the chromosomal analysis of eight araneid species (Acacesia benigna Glueck, 1994, Actinosoma pentacanthum (Walckenaer, 1841), Alpaida bicornuta (Taczanowski, 1878), Dubiepeira Levi, 1991 sp., Gasteracantha cancriformis (Linnaeus, 1758), Parawixia bistriata (Rengger, 1836), Verrucosa meridionalis (Keyserling, 1892) and Verrucosa scapofracta Lise, Kesster & Silva, 2015), contribute to discussions of some evolutionary scenarios of chromosome evolution. The gonads were submitted to colchicine treatment, hypotonization, slide preparation, and Giemsa staining. The species analyzed showed 2n♂ = 24 (11II + X1X2), except Dubiepeira sp. with 2n♂ = 41 (19II + X1X2X3), and both Verrucosa species, which presented 2n♂ = 47 (22II + X1X2X3) in V. meridionalis and 2n♂ = 50 (23II + X1X2X3X4) in V. scapofracta. The species analyzed possess all chromosomes with acro/telocentric chromosomal morphology. The 2n♂ = 24, X1X2 found in most species studied here is the most frequent karyotype in the Araneidae. This study presents the first chromosomal data for the diverse clade "Micrathenines", the highest diploid number among entelegynes (2n♂ = 50), and the first record of an X1X2X3X4 in the Araneidae. The chromosome data suggest a series of fission events in the origin of Verrucosa karyotypes, and a close relationship between Dubiepeira sp. and Araneus ventricosus (L. Koch, 1878). Moreover, Alpaida bicornuta can be cytotaxonomically distinguished of other Alpaida species karyotyped up to now. [ABSTRACT FROM AUTHOR]

We present an ant and spider species list from five localities of the Metropolitan Region of Salvador (MRS). The MRS is placed in an Atlantic Forest area classified as dense broadleaf forest, considered to be of high biological importance and priority for conservation. We determined 198 species of ants (8 of these are considered to be synanthropic and/or exotic), distributed across nine subfamilies. We determined 164 species of spiders (14 of them being synanthropic and/or exotic), distributed across thirty families. Therefore, this survey shows that the urban environment of the MRS still harbors a large number of native fauna species. [ABSTRACT FROM AUTHOR]