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Laboratory ecotoxicological tests are important tools for the management of environmental changes derived from anthropogenic activities. Folsomia candida is usually the model species used in some procedures. However, this species may not be sufficiently representative of the sensitivity of the other collembolan species. This study aimed to evaluate (i) the effects of soils naturally rich in potentially toxic elements (PTE) and soil characteristics on the reproduction and survival of different collembolan species, (ii) whether the habitat function of these soils is compromised, and (iii) to what extent F. candida is representative of the other collembolan species. For this, reproduction tests with six collembolan species were conducted in 14 different samples of soils. In general, collembolan reproduction was not completely inhibited in none of the natural tested soils. Even soils with high pollution load index values did not negatively affect collembolan reproduction for most of the species. In contrast, the lowest collembolan reproduction rates were found in a visually dense soil (lowest volume/weight ratio), highlighting that soil attributes other than total PTE concentration also interfere in the reproduction of collembolans. Our results support the idea that the F. candida species might not be representative of other collembolan species and that laboratory tests to assess soil contaminations should be conducted using diverse collembolan species.

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Ecosystem sustainable use requires reliable information about its biotic and abiotic structure and functioning. Accurate knowledge of trophic relations is central for the understanding of ecosystem dynamics, which in turn, is essential for food web stability analyzes and the development of sustainable practices. There is a rapid growth in the knowledge on how belowground biodiversity regulates the structure and functioning of terrestrial ecosystems. Although, the available information about trophic relationships is hard to find and fragmented. Most of the information available worldwide about the food resources of soil microarthropods suggested that out of 3105 hits of initial research on this aspect only a total of 196 published works related particular species, genera, and families to particular trophic resources, the majority of them dealing with soils of the Palearctic region. From the 196 publications we extracted 3009 records relating specific taxonomic groups to their trophic resources, 20 percent mention saprophytic fungi as a food resource, 16 percent cite microfauna, 11 percent mention bacteria, 10 percent litter and 8 percent cite Springtails. The available information was highly skewed, the 73.71 percent comes from Acari, and within these, 50.62 percent correspond just to Sarcoptiformes. The literature on Collembola is very scarce and most of the information is on arthropleona. The review also highlights that available research on the use of trophic resources comes from European sites and the information on this aspect from other parts of the soils of the world is still at large but unknown.

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Sewage sludge usage as agricultural soil amendment is a well-known practice employed worldwide. However, certain components may pose risks to the soil ecosystem. For a better verification of the potential adverse effects on the soil biota, biological assays have become an indispensable tool for an accurate understanding of the residue's behavior on soil, as well as its potential toxicity. Accordingly, to properly assess the effects of natural tropical soil (Oxisoil) amended with sewage sludge, we conducted toxicological tests with edaphic organisms (Enchytraeus crypticus and Folsomia candida) and microbial biomass (through respirometric assessment). Results indicate that E. crypticus and F. candida present similar reproduction sensitivity behavior to sewage sludge. For the microbiological analysis, the results suggest that microbial activity was stimulated by sludge application. For further evaluation of respiration of the microbial community and CO2 stabilization values behavior, Ford-Walford modeling was applied and presented limit values for sludge application in soil for 1.5 g kg-1 and 15.0 g kg-1 of, approximately, 55 mg and 88 mg, respectively. CO2 releases were faster and reached stability within 18 weeks for the soil with higher sludge content (15.0 g kg-1 of dry soil). In contrast, CO2 releases were slower for the soil with lower sludge content (1.5 g kg-1 of dry soil), and until the experiment's final period (21 weeks) respiration behavior did not reach stability. This study indicates that the stabilized sewage sludge, at the considered recommended application rate, presents a low toxicity risk for the studied bioindicators, being suitable for agricultural use.

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In this contribution, supplementary descriptions of Cyphoderus innominatus Mills, 1938 and C. limboxiphius nitricola Rapoport & Izarra, 1962 are provided; and three new species are described: C. adversus sp. nov., C. amazonicus sp. nov., and C. parafolsomi sp. nov.; chaetotaxy for all of them is included. The new species have a labial triangular field with a1-5, m, e, l1 smooth chaetae, and l2 as reduced spine, but C. adversus sp. nov. is characterized by a trochateral organ with at least 9 spine-like chaetae; tenent hair capitate; colophore chaeta D mic, lateral flap chaetae with uneven length; dens with De1-De6/Di1-Di6 feathered chaetae; mucro only with a, while C. amazonicus sp. nov. is differentiated by a trochateral organ with at least 16 spine-like chaetae; tenent hair acuminate; colophore chaeta D mac, lateral flap chaetae small and subequal; dens with De1-De6/Di1-Di5 feathered chaetae; mucro with aA. Cyphoderus parafolsomi sp. nov. has trochateral organ with more than 14 spine-like chaetae; unguis with 1 unpaired internal tooth; tenent hair capitate; dens with De1-De6/Di1-Di5 feathered chaetae; mucro with aA. A key for identification of the Neotropical species is provided. Also, the paper describes the information about the association of Cyphoderus with different ant species, and a new taxonomic status for C. nitricola (Rapoport & Izarra, 1962) comb. nov.

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Background: Soil-dwelling organisms populate the spaces-referred to as interstices-between the litter on the soil surface and the pores in the soil's organo-mineral matrix. These organisms have pivotal roles in soil ecosystem functions, such as the breakdown and decomposition of organic matter, the dispersal of bacterial and fungal spores and biological habitat transformation. These functions, in turn, contribute to broader ecosystem services like carbon and nutrient cycling, soil organic matter regulation and both chemical and physical soil fertility.This study provides morphological data pertaining to a range of soil organism sizes, specifically in Argiudol soils subjected to varying levels of agricultural activity in the Rolling Pampas Region, one of the world's most extensive and fertile plains.The primary focus is on soil microarthropods-namely, Acari (mites) and Collembola (springtails)-with a body width of less than 2 mm. These organisms constitute the majority of life in the intricate soil pore network. Additionally, the study documents species of earthworms (Oligochaeta, Crassiclitelata), recognised as ecosystem engineers for their ability to create physical channels in the soil matrix and to distribute organic matter. Moreover, the study includes measurements of morphological traits of soil-dwelling "macrofauna" (organisms with a body width greater than 2 mm), which are also implicated in various soil ecosystem functions. These include population regulation by apex predators, organic matter decomposition, biogenic structure formation, nutrient mobilisation and herbivory. New information: In this paper, we report both the geographical locations and individual measurements of key morphological traits for over 7,000 specimens, covering a range of soil-dwelling organisms. These include springtails (Entognatha, Collembola), mites (Arachnida, Acari), earthworms (Oligochaeta, Crassiclitellata) and additional soil macrofauna. All specimens were collected from typical Argiudol soils located in three distinct agricultural systems characterised by varying levels of land-use intensity. To our knowledge, no other dataset exists providing this information for the Argentinian Pampas.

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Two new species of Cyphoderus are described; full body chaetotaxy is given. Cyphoderus pataxo sp. nov. and Cyphoderus palaciosi sp. nov. were originally found in metalogenic areas covered with transitional vegetation of savanna and subtropical forest from Minas Gerais, Southeastern Brazil. Both new species are part of the "bidenticulati-group," with mucronal formula 'Aa' and show remarkable plurichaetosis on posterior manubrium and dens.

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We present new species and records of Poduromorpha for the Brazilian oceanic islands and synthesis of this order in Brazil. Friesea noronhaensis sp. nov., Friesea rochedoensis sp. nov., Willemia insularum sp. nov. and Paraxenylla zeliae sp. nov. are described and a diagnosis of the morphospecies Acherontiella sp. Lima and Zeppelini 2015 is provided. We present comparative tables, distribution and taxonomic keys of the Friesea, Arlesia, Brachystomella, Acherontiella, Paraxenylla, Xenylla, and Willemia found in the Brazilian oceanic islands and their respective congeners recorded in Brazil.

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The new genus Borgesminthurinus gen. nov. from Bolivia shares with Sminthurinus the presence of antennal segment IV undivided, antennal segment III with one papilla; sacs of ventral tube smooth; each tenacular rami with 3 teeth and a basal appendix. They also have dens with ventral chaetotaxy reduced and lack mucronal seta; but new genus clearly differs in having thick and barbulate setae on head and body, lacking neosminthuroid setae on abdomen and the presence of seta a0 on Abd. VI acuminate. The new genus differs from Katianna which has divided antennal segment IV, vertex of head with spine-like setae and setae of the body long and smooth.

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A new Hypogastrura species of the nivicola group from Canada is described and illustrated. The new species is characterized by postantennal organ with outer anterior lobe elongated, head interocular tubercles not prominent, all terga with some extra chaetae, dens dorsally with 8-9 conical, bi- or tridentate spines, and a boat-shaped mucro with subapical tooth. A discussion on the morphology of the nivicola group is given and an identification key for all eight species of this group found in the Nearctic is provided.

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Entomobrya Rondani, 1861 is one of the largest genera of springtails and the most diverse group of scaleless Entomobryoidea. Only 14 species of Entomobrya were recorded from Brazil so far. Herein we present two new Brazilian species of the genus. Entomobrya juneae sp. nov. can be diagnosed by antennae shorter or as long as the trunk; prelabral and labial chaeta e smooth, mesothorax lacking m5 and p5 macrochaetae, mucro distal tooth reduced, among other features. It is somehow similar to E. atrocincta Schött, 1896 and E. nivalis (Linnaeus, 1758) sensu Katz et al. (2015) in some aspects of dorsal chaetotaxy, but the new species presents less macrochaetae on mesothorax and third and fourth abdominal segments. Entomobrya barbata sp. nov. is quite similar to E. linda Soto-Adames 2002 especially due to its remarkable reduced dorsal chaetotaxy, but can be separated from it in dorsal head, mesothorax, fourth abdominal segment and manubrial plate chaetotaxy. We also investigate the similarities of Brazilian Entomobrya species with Entomobryoides Maynard, 1951 and provide comments on the morphology of both genera.

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A new genus and two new species of Sminthurinae are described. Keratosminthurus tapigu gen. nov. sp. nov. and K. calamitosus sp. nov. show a combination of features that redefines the subfamily Sminthurinae, such as a pair of sminthuroid chaetae, unguis without cavity, nine apical chaetae on tibiotarsus, 11 or more anterior dental chaetae, fourth antennal segment clearly subdivided into many (18 or more) subsegments, and asymmetric apex of mucro. The new genus also presents a striking sexual dimorphism, with modifications on male apical organ of antennal segment III, spines on the clypeus and special organs on the interocular area.

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Herein Lepidocyrtinus Börner is reviewed based on African species and a new diagnosis to the genus is provided, including the description of intermediary stages of two species and a proposal for the interpretation of the dorsal chaetotaxy based in juveniles. In total, 17 species previously assigned as Seira Lubbock are transferred to Lepidocyrtinus, and three of them are redescribed: L. barnardi Womersley and L. dayi Yosii from South Africa, and L. voeltzkowi (Börner) from Madagascar. Neotypes are designated for these last two species. In addition, nine new species are described from Africa: one from Botswana, two from Republic of the Congo, two from South Africa, and four from Madagascar. Finally, identification keys for the current genera of Seirinae and for the African species of Lepidocyrtinus are provided. After our revision, Lepidocyrtinus has now its generic status revalidated with 36 species, 29 of them from African continent, two from Oceania and five from Brazil.

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A new blind species, Folsomides cariocus sp. nov., which belongs to the F. parvulus group sensu Fjellberg (1993), is described and illustrated based on material collected in compacted clay soil covered by undergrowth and no litter around the bee nest holes at the Botanical Garden, located in Rio de Janeiro City. The new species is very similar to F. parvulus Stach, 1922 but differs mainly due to the absence of eyes. Synonymies based on ocular variations and pigmented spots were discussed and a table for the group parvulus species is present.

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Aethiopella Handschin, 1942 as other Pseudachorutinae (Neanuridae) presents a diagnosis with overlapping characters when compared to other similar genera, especially Halachorutes Arlé, 1966, Ceratrimeria Börner, 1906 and Pseudachorutes Tullberg, 1871. This condition, combined to several gaps on the knowledge of described species and a wide range of morphological differences within the genus, reinforces the need of its revision, since it can be an artificial group. In spite of that, a new species, Aethiopella ricardoi sp. nov., is described and illustrated. It resembles the other five Neotropical taxa of Aethiopella but is unique by the combination of fourth antennal segment with trilobed apical bulb and 7 dorsal sensilla, lack of dorsolateral S-microchaeta (ms); postantennal organ with 13-19 vesicles; mandibles with 7-8 teeth; maxillae apically hooked; and tibiotarsi I-III with 19/19/18 chaetae, respectively, with M chaeta slightly basally displaced. We also present an updated diagnosis of Aethiopella based on current knowledge of Pseudachorutinae, a table comparing all species, a key to Neotropical taxa and remarks on the genus.

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Willemia panamaensis sp. nov. from Panama is described and illustrated. It is characterised by the presence of sensilla I (S2) and i1 (S9) on antennal segment IV, nine vesicles in the postantennal organ, and having dorsal setae and sensilla on abdominal segments V and VI twice as long than on segments I and II. A dichotomous key to species recorded from the Americas is provided. Reference is given to the DNA barcoding sequences of the new species.

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Temeritas Richards is a small genus of Sminthuridae with 40 species described worldwide, 10 of them from Neotropical Region. Herein we describe in detail two new species of the genus from Brazil: T. andreazzei sp. nov., similar to other neotropical taxa such T. amazonensis Arlé Oliveira and T. caatingae Arlé Oliveira in the presence of several long chaetae on body and appendages, absence of oval organs on tibiotarsi and presence of mucronal chaeta, but can be readily separate from both by its exclusive combination of fourth antennal segment articles and head, male's parafurcal area and dorsal dens chaetotaxy; and T. paradoxalis sp. nov., unique in the genus by the combination of low number of fourth antennal segment articles, absence of remarkably long chaetae on third and second antennal segments and head, ungues with serrated dorsal and lateral margins, and mucronal chaeta absent. We also present an updated diagnosis, a comparison of neotropical Temeritas with an identification key to these species and notes on the genus.

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Tyranonoseira is revised and new diagnostic characters to the genus and its species are proposed. The genus is now characterised by distinct chaetotaxic patterns of head, in lacking M2, S1, S4, S5 macrochaetae and Th II to Abd IV with 21-27, 7, 0, 3, 1 and 8-10 central macrochaetae, as well as anterior legs of males with modified chaetae. The five species of the genus are redescribed based on type material: T. raptora Zeppelini Bellini, T. bicolorcornuta Bellini Zeppelini, T. diabolica Bellini Godeiro, T. gladiata Zeppelini Lima and T. sex Bellini Zeppelini. We include an identification key and comparison of the species. The dorsal chaetotaxy is similar for all species. Characters omitted from the original descriptions such as chaetotaxy of the clypeus, labral papillae, collophore chaetae and manubrial formula are now used to distinguish species more clearly. We compare the morphology of Seira and Tyrannoseira using dorsal chaetotaxy and the modified chaetae on anterior legs of males.

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A second species of Acherontides from Brazil is described. Acherontides serrasapoensis sp. nov. has two ocular area chaetae, tenaculum with 3+3, two clavate tenent hairs, and anal spines about 1/3 the length of unguis III. A comparative table is presented and an identification key for the species of Acherontides.

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A new species of Nothobrya Arlé is described and illustrated. The specimens were collected in Serra da Capivara National Park and its vicinities, Caatinga Biome, Piauí State, Brazil, from soil and leaf litter samples. Nothobrya sertaneja sp. nov. differs from the two previously described species of the genus, N. arlei Silveira Mendonça and N. schubarti Arlé, by antennae with 4-5 antennomeres (6 in N. arlei and N. schubarti); metatrochanteral organ with 7-13 spine-like chaetae (15 in N. arlei and 3-4 in N. schubarti); tenaculum with 2-3 smooth chaetae on corpus (4 ciliated chaetae in N. arlei and 2 chaetae with unclear morphology in N. schubarti); and inner unguis with 2 basal paired teeth, 1 median and 1 apical tooth (2 basal paired, 1 median and 2 lateral teeth in N. arlei and 2 basal paired and 0-1 unpaired median tooth in N. schubarti). We present herein the first complete and labelled dorsal chaetotaxy description of the genus and the entire subfamily, including the S-chaetotaxy of the tergal segments. Finally, we also provide a new diagnosis to Nothobrya, plus an identification key to species of Nothobryinae.

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A taxonomic list of recorded Symphypleona from Mexico is presented. Data also includes a nomenclatorial update, distribution per political entity and habitat preferences. It is indicated that 28 genera and 73 species are currently distributed in 23 of the 32 states of Mexico. Quintana Roo represents the most diverse state (27 species) followed by Jalisco and Hidalgo (20 spp.). Reviews consulted indicate that eleven endemic species have been recorded so far from Mexico. According to the literature, one-third of the collected specimens across Mexico from leaf litter have yielded Symphypleona. The three most diverse genera recorded are, Sminthurides with 9 species, Sminthurinus and Sminthurus with 7 species each.

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