The Chemistry of the Defensive Secretions of Three Species of Millipedes in the Genus Brachycybe.

Millipedes have long been known to produce a diverse array of chemical defense agents that deter predation. These compounds, or their precursors, are stored in high concentration within glands (ozadenes) and are released upon disturbance. The subterclass Colobognatha contains four orders of millipedes, all of which are known to produce terpenoid alkaloids-spare the Siphonophorida that produce terpenes. Although these compounds represent some of the most structurally-intriguing millipede-derived natural products, they are the least studied class of millipede defensive secretions. Here, we describe the chemistry of millipede defensive secretions from three species of Brachycybe: Brachycybe producta, Brachycybe petasata, and Brachycybe rosea. Chemical investigations using mass spectrometry-based metabolomics, chemical synthesis, and 2D NMR led to the identification of five alkaloids, three of which are new to the literature. All identified compounds are monoterpene alkaloids with the new compounds representing indolizidine (i.e. hydrogosodesmine) and quinolizidine alkaloids (i.e. homogosodesmine and homo-hydrogosodesmine). The chemical diversity of these compounds tracks the known species phylogeny of this genus, rather than the geographical proximity of the species. The indolizidines and quinolizidines are produced by non-sympatric sister species, B. producta and B. petasata, while deoxybuzonamine is produced by another set of non-sympatric sister species, B. rosea and Brachycybe lecontii. The fidelity between the chemical diversity and phylogeny strongly suggests that millipedes generate these complex defensive agents de novo and begins to provide insights into the evolution of their biochemical pathways.

Evaluation of the consumption of agricultural and urban waste by the diplopod Trigoniulus corallinus as a strategy for formulating new combinations for the millicomposting process.

This study aimed to measure the consumption of different types of plant waste by the diplopod species Trigoniulus corallinus, in order to determine which would be the most suitable for the millicomposting process. To this end, a waste consumption experiment was carried out in the laboratory, using a completely randomized experimental design with 15 replicates and 13 organic residues from different sources. After 10 days, the following parameters were evaluated: dry mass of the waste used to feed the diplopods, dry mass of the fecal pellets, and diplopod mortality. Significant differences were observed in the consumption rates of the diplopods in the different treatments, with the highest rates being observed for Mimosa caesalpiniifolia, with 44.49%, followed by Gliricidia sepium chips, with 38.24%. The highest values for pellet mass were obtained from the decomposition of Mimosa caesalpiniifolia litter (0.891 g). The treatment with Syngonium auritum shavings showed 93% mortality after consumption, followed by the treatment with Heliconia psittacorum shavings, which showed 53%. Both species are ornamental and widely found in gardens and backyards. The diplopods have a preference for Mimosa caesalpiniifolia litter and Gliricidia sepium shavings. There is limited consumption of ornamental plant waste, with reports of toxicity to other organisms. Based on these results, a mixture of waste will be tested for millicomposting in urban farming areas that excludes toxic plants.

A new species of Lophostreptus Cook, 1895 discovered among syntypes of L.regularis Attems, 1909 (Diplopoda, Spirostreptida, Spirostreptidae).

A new species of the genus Lophostreptus Cook, 1895 is described, based on specimens hidden for over a century among the syntypes of its congener Lophostreptusregularis Attems, 1909 housed in the Naturhistoriska Riksmuseet Stockholm (NRMS) and the Naturhistorisches Museum Wien (NHMW). A lectotype is designated for Lophostreptusregularis Attems, 1909 in order to stabilize its taxonomy. Updates to the millipede fauna of Mt. Kilimanjaro, Tanzania are provided.

Rapid divergent evolution of internal female genitalia and the coevolution of male genital morphology revealed by micro-computed tomography.

Animal genitalia are thought to evolve rapidly and divergently in response to sexual selection. Studies of genital evolution have focused largely on male genitalia. The paucity of work on female genital morphology is probably due to problems faced in quantifying shape variation, due to their composition and accessibility. Here we use a combination of micro-computed tomography, landmark free shape quantification and phylogenetic analysis to quantify the rate of female genital shape evolution among 29 species of Antichiropus millipedes, and their coevolution with male genitalia. We found significant variation in female and male genital shape among species. Male genital shape showed a stronger phylogenetic signal than female genital shape, although the phylogenetic signal effect sizes did not differ significantly. Male genital shape was found to be evolving 1.2 times faster than female genital shape. Female and male genital shape exhibited strong correlated evolution, indicating that genital shape changes in one sex are associated with corresponding changes in the genital shape of the other sex. This study adds novel insight into our growing understanding of how female genitalia can evolve rapidly and divergently, and highlights the advantages of three-dimensional techniques and multivariate analyses in studies of female genital evolution.

Diversity and taxonomic revision of methanogens and other archaea in the intestinal tract of terrestrial arthropods.

Methane emission by terrestrial invertebrates is restricted to millipedes, termites, cockroaches, and scarab beetles. The arthropod-associated archaea known to date belong to the orders Methanobacteriales, Methanomassiliicoccales, Methanomicrobiales, and Methanosarcinales, and in a few cases also to non-methanogenic Nitrososphaerales and Bathyarchaeales. However, all major host groups are severely undersampled, and the taxonomy of existing lineages is not well developed. Full-length 16S rRNA gene sequences and genomes of arthropod-associated archaea are scarce, reference databases lack resolution, and the names of many taxa are either not validly published or under-classified and require revision. Here, we investigated the diversity of archaea in a wide range of methane-emitting arthropods, combining phylogenomic analysis of isolates and metagenome-assembled genomes (MAGs) with amplicon sequencing of full-length 16S rRNA genes. Our results allowed us to describe numerous new species in hitherto undescribed taxa among the orders Methanobacteriales (Methanacia, Methanarmilla, Methanobaculum, Methanobinarius, Methanocatella, Methanoflexus, Methanorudis, and Methanovirga, all gen. nova), Methanomicrobiales (Methanofilum and Methanorbis, both gen. nova), Methanosarcinales (Methanofrustulum and Methanolapillus, both gen. nova), Methanomassiliicoccales (Methanomethylophilaceae fam. nov., Methanarcanum, Methanogranum, Methanomethylophilus, Methanomicula, Methanoplasma, Methanoprimaticola, all gen. nova), and the new family Bathycorpusculaceae (Bathycorpusculum gen. nov.). Reclassification of amplicon libraries from this and previous studies using this new taxonomic framework revealed that arthropods harbor only CO2 and methyl-reducing hydrogenotrophic methanogens. Numerous genus-level lineages appear to be present exclusively in arthropods, suggesting long evolutionary trajectories with their termite, cockroach, and millipede hosts, and a radiation into various microhabitats and ecological niches provided by their digestive tracts (e.g., hindgut compartments, gut wall, or anaerobic protists). The distribution patterns among the different host groups are often complex, indicating a mixed mode of transmission and a parallel evolution of invertebrate and vertebrate-associated lineages.

Some Aspects of the Physiology of the Nyctotherus velox, a Commensal Ciliated Protozoon Taken from the Hindgut of the Tropical Millipede Archispirostreptus gigas.

In this paper, the growth requirements, fermentation pattern, and hydrolytic enzymatic activities of anaerobic ciliates collected from the hindgut of the African tropical millipede Archispirostreptus gigas are described. Single-cell molecular analysis showed that ciliates from the millipede hindgut could be assigned to the Nyctotherus velox and a new species named N. archispirostreptae n. sp. The ciliate N. velox can grow in vitro with unspecified prokaryotic populations and various plant polysaccharides (rice starch-RS, xylan, crystalline cellulose20-CC, carboxymethylcellulose-CMC, and inulin) or without polysaccharides (NoPOS) in complex reduced medium with soluble supplements (peptone, glucose, and vitamins). Specific catalytic activity (nkat/g of protein) of α amylase of 300, xylanase of 290, carboxymethylcellulase of 190, and inulinase of 170 was present in the crude protein extract of N. velox. The highest in vitro dry matter digestibility was observed in RS and inulin after 96 h of fermentation. The highest methane concentration was observed in xylan and inulin substrates. The highest short-chain fatty acid concentration was observed in RS, inulin, and xylan. In contrast, the highest ammonia concentration was observed in NoPOS, CMC, and CC. The results indicate that starch is the preferred substrate of the N. velox. Hydrolytic enzyme activities of N. velox showed that the ciliates contribute to the fermentation of plant polysaccharides in the gut of millipedes.

Factors affecting the biodiversity of historical landscape elements: detailed analyses from three case studies in Slovakia.

A direct, positive correlation between biodiversity and the traditional agricultural landscape is evident on the national or regional scale. It is mostly conditioned by higher landscape diversity and less intensive farming. We have carried out research on a detailed scale at plot level (productive plots of arable lands, grasslands, vineyards, orchards, and unproductive agrarian landforms (mostly field margins) such as terraced slopes, terraced steps, heaps, mounds, and unconsolidated walls) in three traditional agricultural landscapes: the mountain village Liptovská Teplicka, the vineyard landscape in Svätý Jur, and dispersed settlements in a submontane area in Hrinová. We determined the statistical significance of the impact of the selected landscape ecological factors (a set of factors concerning land use and management, agrarian landforms and relief properties) on the distribution of vegetation and selected invertebrate groups (spiders, millipedes, grasshoppers, and crickets). We also explored whether maintaining traditional land use and traditional management helped to enhance the biodiversity. We found that the management regime is the most important factor determining the species composition of vascular plants and all studied animal groups. Also, present land use and agrarian landforms character (type, skeleton content, continuity) are significant factors. Our expectation of a positive relationship between biodiversity and the maintaining traditional land use and traditional management was, in general, not confirmed: such a relation was only found in Svätý Jur for biodiversity of spiders.

Identification and biodiversity patterns of Aspergillus species isolated from some soil invertebrates at high altitude using morphological characteristics and phylogenetic analyses.

Background: The carcinogenic, mutagenic, and teratogenic chemicals such as aflatoxin are a worldwide health problem. Aspergillus spp., responsible for most cases of aflatoxin contamination, are common in the environment and spread easily to many different types of food. The objectives of this study were to conduct a survey of fungi associated with three soil invertebrates in Taif, Saudi Arabia, identify these isolates and explore mycotoxins formation. Methods: In total, 114 fungal isolates were collected from various soil invertebrates (millipedes, Armadillidium vulgare and Porcellio laevis) in Taif, Saudi Arabia, among them, 22 isolates were identified as Aspergillus spp. based on morphological and molecular characteristics followed by both Fusarium and Penicillium. Results: The sequences of ITS 1 and ITS 4 were utilized. Using bootstrap analysis, phylogenetic tree was split into two distinct clusters. Five sub clusters were included inside the first major cluster, and their bootstrap value was 99%. While, there were two small clusters in the second major cluster. All the tested Aspergillus strains were able to have a single PCR fragment amplified using the primer AspTef. TEF-1 DNA sequence bootstrap analysis with 1,000 replicates revealed two distinct groups. Additionally, the Aspergillus isolates were grouped into two different clusters with about 65% genetic similarity using ISSR-PCR analysis. The standard polymerase chain reaction was used to effectively amplify the Aopks, afl-A and omt-A genes in aflatoxigenic Aspergillus strains. Four Aspergillus strains used in this investigation were shown to generate aflatoxin B1. While, three Aspergillus stains showed ochratoxin genes. Conclusions: In conclusion, the results indicate significant differences in the fungal community between ecoregions and soil invertebrates. Moreover, mycotoxin detection and identification among Aspergillus isolates were elucidated. This study could shed light on the risk of mycotoxin contamination along the supply chain.

Effect of gluten on the digestive tract and fat body of Telodeinopus aoutii (Diplopoda).

Adult specimens or larvae of invertebrates used as food for vertebrates are often maintained close to gluten so they might become vectors for cereal proteins. However, the tissues and internal organs can respond differently in animals with different feeding habits. The midgut epithelium might be a first and sufficient barrier preventing uptake and effects of gluten on the whole body, while the fat body is the main organ that accumulates different xenobiotics. Good models for such research are animals that do not feed on gluten-rich products in their natural environment. The project's goal was to investigate alterations in the midgut epithelium and fat body of the herbivorous millipede Telodeinopus aoutii (Diplopoda) and analyze cell death processes activated by gluten. It enabled us to determine whether changes were intensified or reversed by adaptive mechanisms. Adult specimens were divided into control and experimental animals fed with mushrooms supplemented with gluten and analyzed using transmission electron microscopy, flow cytometry, and confocal microscopy. Two organs were isolated for the qualitative and quantitative analysis: the midgut and the fat body. Our study of the herbivorous T. aoutii which does not naturally feed on gluten containing diet showed that continuous and prolonged gluten feeding activates repair processes that inhibit the processes of cell death (apoptosis and necrosis) and induce an increase in cell viability.

A case of mass occurrence of Sandalodesmus araujoi (Schubart, 1946) in a municipality of São Paulo, Brazil and description of the heretofore unknown female (Polydesmida, Chelodesmidae)

Somatic characters are shared by many Chelodesmidae groups, and generic placement and species identifications traditionally have been based on gonopodal morphology. Female genitalic characters have been largely neglected and are rarely photographed or illustrated. This is rather unfortunate as the morphology of female genitalia presents important characters and may be decisive for developing a more robust family classification. We describe the heretofore unknown female of Sandalodesmus araujoi (Schubart, 1946), previously known only from the male holotype collected in São Paulo, Brazil in December 1943; discuss the utility of female genitalic characters for species delineation in Sandalodesmus; and report the first case of a mass occurrence in the Chelodesmidae. While an attempt at a formal diagnosis of Sandalodesmus females based on genitalic characters is premature, the vulvar morphology of the three taxa examined in this study suggests that female genitalia are species-specific. Some characters (i.e., asymmetric valves, presence of digitiform projections and reduction of setae on the internal basal portion of the valves) are constant between the species, suggesting utility for generic-level delineation. Mass occurrences of millipedes are typically unpredictable and likely related to variations in environmental conditions and/or anthropogenic modifications of natural habitats. Although the mass occurrence of S. araujoi reported herein was only observed once, the event coincides with the mating period of millipedes during the rainy season in Brazil. On the other hand, the region where the species was found has been the target of intense urban development, including replacement of natural habitats with residential areas, which may have influenced its population dynamics.

Os caracteres somáticos são compartilhados por muitos grupos de Chelodesmidae, e o posicionamento genérico e as identificações de espécies tradicionalmente têm sido baseadas na morfologia do gonópodo. Carateres genitais das fêmeas foram amplamente negligenciados e raramente são fotografados ou ilustrados. Isso é lamentável, pois a morfologia da genitália feminina apresenta características importantes e pode ser decisiva para o desenvolvimento de uma classificação mais robusta. Neste trabalho, descrevemos a até então desconhecida fêmea de Sandalodesmus araujoi (Schubart, 1946)

A case of mass occurrence of Sandalodesmus araujoi () in a municipality of São Paulo, Brazil and description of the heretofore unknown female (Polydesmida, Chelodesmidae) / Um caso de ocorrência em massa de Sandalodesmus araujoi () em um município de São Paulo, Brasil e descrição da fêmea até então desconhecida (Polydesmida, Chelodesmidae)

Abstract Somatic characters are shared by many Chelodesmidae groups, and generic placement and species identifications traditionally have been based on gonopodal morphology. Female genitalic characters have been largely neglected and are rarely photographed or illustrated. This is rather unfortunate as the morphology of female genitalia presents important characters and may be decisive for developing a more robust family classification. We describe the heretofore unknown female of Sandalodesmus araujoi (Schubart, 1946), previously known only from the male holotype collected in São Paulo, Brazil in December 1943; discuss the utility of female genitalic characters for species delineation in Sandalodesmus; and report the first case of a mass occurrence in the Chelodesmidae. While an attempt at a formal diagnosis of Sandalodesmus females based on genitalic characters is premature, the vulvar morphology of the three taxa examined in this study suggests that female genitalia are species-specific. Some characters (i.e., asymmetric valves, presence of digitiform projections and reduction of setae on the internal basal portion of the valves) are constant between the species, suggesting utility for generic-level delineation. Mass occurrences of millipedes are typically unpredictable and likely related to variations in environmental conditions and/or anthropogenic modifications of natural habitats. Although the mass occurrence of S. araujoi reported herein was only observed once, the event coincides with the mating period of millipedes during the rainy season in Brazil. On the other hand, the region where the species was found has been the target of intense urban development, including replacement of natural habitats with residential areas, which may have influenced its population dynamics.

Resumo Os caracteres somáticos são compartilhados por muitos grupos de Chelodesmidae, e o posicionamento genérico e as identificações de espécies tradicionalmente têm sido baseadas na morfologia do gonópodo. Carateres genitais das fêmeas foram amplamente negligenciados e raramente são fotografados ou ilustrados. Isso é lamentável, pois a morfologia da genitália feminina apresenta características importantes e pode ser decisiva para o desenvolvimento de uma classificação mais robusta. Neste trabalho, descrevemos a até então desconhecida fêmea de Sandalodesmus araujoi (Schubart, 1946), anteriormente conhecida apenas pelo holótipo macho coletado em São Paulo, Brasil, em dezembro de 1943; discutimos a utilidade de caracteres genitais femininos para delineamento de espécies em Sandalodesmus; e relatamos o primeiro caso de ocorrência em massa para Chelodesmidae. Embora uma tentativa de diagnose formal para fêmeas de Sandalodesmus com base em caracteres genitais seja prematura, a morfologia vulvar dos três táxons examinados neste estudo, sugere que a genitália feminina é espécie-específica. Alguns caracteres (e.g. válvulas assimétricas, presença de projeções digitiformes e redução de cerdas na margem interna das válvas) são constantes entre as espécies do gênero, sugerindo utilidade para delineamento em nível genérico. Ocorrências em massa de milípedes são tipicamente imprevisíveis e provavelmente relacionadas a variações nas condições ambientais e/ou modificações antropogênicas de habitats naturais. Embora a ocorrência em massa de S. araujoi aqui relatada tenha sido observada apenas uma vez, o evento coincide com o período de reprodução dos milípedes durante a estação chuvosa no Brasil. Por outro lado, a região onde a espécie foi encontrada tem sido alvo de intenso desenvolvimento urbano, incluindo substituição de habitats naturais por áreas residenciais, o que pode ter influenciado sua dinâmica populacional.

A review of the cavernicolous Trichopolydesmidae (Diplopoda, Polydesmida) from the Carpathian-Balkan arch and the Rhodope Mountains, with descriptions of two new genera and three new species.

All cavernicolous species of the millipede family Trichopolydesmidae from the Carpathian-Balkan arch and the Rhodope Mountains have been reviewed. At present the family has been shown to comprise five or six genera with eight or nine species. Two new genera have been described, viz., Balkanodesminus gen. nov., with two new species: B.dentatoides sp. nov. and B.serbicus sp. nov., from Bulgaria and Serbia, respectively, and the monospecific Rhodopodesmus gen. nov., with R.niveus sp. nov., from Bulgaria. Two new combinations and one new status have been proposed: Balkanodesminusbulgaricus (Strasser, 1962) comb. nov. ex Bacillidesmusbulgaricus Strasser, 1962 and Balkanodesminusdentatus (Strasser, 1966a) comb. nov., stat. nov. ex Bacillidesmusbulgaricusdentatus Strasser, 1966a. All genera and species are diagnosed with the inclusion of the most relevant remarks for each of them. Old museum types are checked for Bacillidesmusfiliformis (Latzel, 1884) with lectotype designation, as well as for Trichopolydesmuseremitis Verhoeff, 1898. An identification key to all six genera and a distribution map for the eight species are provided, as well as brief remarks and general considerations on the family Trichopolydesmidae.

Diversity and abundance of soil macroinvertebrates along a contamination gradient in the Central Urals, Russia.

BACKGROUND: Since the late 1980s, long-term monitoring of terrestrial ecosystems in metal-contaminated areas near the Middle Ural Copper Smelter has been carried out in the Central Urals. As a part of these monitoring programmes, the data on species diversity, community composition and abundance of soil macroinvertebrates continue to be gathered. NEW INFORMATION: The dataset (available from the GBIF network at https://www.gbif.org/dataset/61e92984-382b-4158-be6b-e391c7ed5a64) includes a 2004 census for soil macroinvertebrates of spruce-fir forests along a pollution gradient in the Central Urals. The dataset describes soil macrofauna's abundance (the number of individuals per sample, i.e. the density) and community structure (list of supraspecific taxa, list of species for most abundant taxa and supraspecific taxa or species abundance). Seventeen sampling plots differed in the levels of toxic metal (Cu, Zn, Pb, Cd and Fe) soil contamination from air emissions of the Middle Ural Copper Smelter (heavily polluted, moderately polluted and unpolluted areas). The dataset consists of 340 sampling events (= samples corresponding to upper and lower layers of the 170 soil monoliths) and 64658 rows (2907 and 61751 for non-zero and zero density of taxa, respectively). Arachnida (Araneae and Opiliones), Carabidae (imagoes), Elateridae (larvae), Chilopoda, Diplopoda, Gastropoda, Staphylinidae (imagoes) and Lumbricidae were identified to species level. In contrast, Mermithida, Enchytraeidae, Lepidoptera larvae, Diptera larvae, Hemiptera, Hymenoptera and some other insects were identified to family or order levels. In total, 8430 individuals of soil macroinvertebrates were collected in two soil layers (organic and organic-mineral horizons), including 1046 Arachnida (spiders and harvestmen), 45 Carabidae, 300 Elateridae, 529 Myriapoda, 741 Gastropoda, 437 Staphylinidae, 623 Lumbricidae and 4709 other invertebrates. The presence-absence data on each taxon are provided for each sampling event. An overwhelming majority of such absences can be interpreted as "pseudo-absences" at the scale of sampling plots or study sites. The dataset contains information helpful for long-term ecotoxicological monitoring of forest ecosystems and contributes to studying soil macrofauna diversity in the Urals.

Revealing the millipede and other soil-macrofaunal biodiversity in Hong Kong using a citizen science approach.

Background: Soil biodiversity plays important roles in nutrient recycling in both the environment and agriculture. However, they are generally understudied worldwide. To reveal the diversity of soil macrofauna in Hong Kong, here we initiated a citizen science project involving university, non-governmental organisations and secondary school students and teachers. It is envisioned that the citizen science approach used in this study could be used as a demonstration to future biodiversity sampling and monitoring studies. New information: Throughout a year of monitoring and species sampling across different localities in Hong Kong, 150 soil macrofaunal morphospecies were collected. Eighty five of them were further identified by morphology and DNA barcoding was assigned to each identified morphospecies, yielding a total of 646 DNA barcodes, with new millipede sequences deposited to the GenBank. The soil macrofauna morphospecies in Hong Kong found in this study are mainly dominated by millipedes (23 out of 150) and oligochaetes (15 out of 150). Amongst the twenty three identified millipedes, two polyxenid millipedes, Monographisqueenslandica Huynh & Veenstra, 2013 and Alloproctoidesremyi Marquet and Condé, 1950 are first recorded in Hong Kong. Information has been curated on an online platform and database (http://biodiversity.sls.cuhk.edu.hk/millipedes). A postcard summarising the findings of millipedes in Hong Kong has also been made as a souvenir and distributed to citizen participants. The identified macrofauna morphospecies and their 646 DNA barcodes in this study established a solid foundation for further research in soil biodiversity.

Worldwide distribution of cave-dwelling Chelodesmidae (Diplopoda, Polydesmida)

Chelodesmidae is one of the most species rich families within the Myriapoda. However, little is known regarding their association with caves. We provide a list of all Chelodesmidae taxa reported from caves, map their worldwide distribution, and discuss the troglomorphic features of the group. A total of 25 species and subspecies from 20 genera and 2 subfamilies have been recorded from 59 caves and cave systems in 11 countries. These numbers represent a surprisingly modest proportion (~3%) of the approximately 800 described species in the family. Records of cave-dwelling chelodesmids appear to be geographically biased with most taxa reported from the Neotropics, likely due to the greater diversity of the group in the region. The lack of published records from the Afrotropics can undoubtedly be attributed to low sampling efforts. In addition, many studies focusing on cave invertebrates, especially in the tropics, often fail to identify chelodesmid taxa to the species level, thus precluding their inclusion on checklists. The majority of the Chelodesmidae reported from caves do not display obvious adaptations to a subterranean lifestyle and are not troglomorphic. The five troglobitic taxa indicated in this study may represent relictual lineages suggesting that few, if any, radiations of chelodesmids within caves have occurred in the past. Increased efforts are needed to bridge the gap between our current understanding and the true diversity of the group in these fragile and threatened habitats, which is necessary to allow policy makers to prioritize appropriate and effective conservation efforts, including the protection of environments severely impacted by human activities.

Sandalodesmus joachimadisi n. sp., the first Chelodesmidae member from Uruguay with an updated key to species of the genus (Diplopoda: Polydesmida)

A new species of Chelodesmidae is described from northern Uruguay, Sandalodesmus joachimadisi n. sp. The new species differs from other congeners by particular features of the gonopods. Sandalodesmus joachimadisi n. sp. belongs to the iguazuensis species group. Photographs of the new species, data on its natural history and a geographic distribution map of all Sandalodesmus species are presented. A key to the species of Sandalodesmus is provided. The taxonomic relationships with other species of the genus are discussed.

Two New Species of the Brazilian Millipede Genus Rhicnosthetus Hoffman, 2006 (Polydesmida: Chelodesmidae), Including a Key to Males.

The genus Rhicnosthetus Hoffman, 2006 is revisited. Two new species from state of Mato Grosso, Brazil are described: Rhicnosthetus chagasi sp. nov. and Rhicnosthetus penabarbosai sp. nov. In addition, a new record for R. rondoni Hoffman, 2006, a key to males and a distribution map of all species are included.

Methanogenesis in the Digestive Tracts of the Tropical Millipedes Archispirostreptus gigas (Diplopoda, Spirostreptidae) and Epibolus pulchripes (Diplopoda, Pachybolidae).

Methanogens represent the final decomposition step in anaerobic degradation of organic matter, occurring in the digestive tracts of various invertebrates. However, factors determining their community structure and activity in distinct gut sections are still debated. In this study, we focused on the tropical millipede species Archispirostreptus gigas (Diplopoda, Spirostreptidae) and Epibolus pulchripes (Diplopoda, Pachybolidae), which release considerable amounts of methane. We aimed to characterize relationships between physicochemical parameters, methane production rates, and methanogen community structure in the two major gut sections, midgut and hindgut. Microsensor measurements revealed that both sections were strictly anoxic, with reducing conditions prevailing in both millipedes. Hydrogen concentration peaked in the anterior hindgut of E. pulchripes. In both species, the intestinal pH was significantly higher in the hindgut than in the midgut. An accumulation of acetate and formate in the gut indicated bacterial fermentation activities in the digestive tracts of both species. Phylogenetic analysis of 16S rRNA genes showed a prevalence of Methanobrevibacter spp. (Methanobacteriales), accompanied by a small fraction of so-far-unclassified "Methanomethylophilaceae" (Methanomassiliicoccales), in both species, which suggests that methanogenesis is mostly hydrogenotrophic. We conclude that anoxic conditions, negative redox potential, and bacterial production of hydrogen and formate promote gut colonization by methanogens. The higher activities of methanogens in the hindgut are explained by the higher pH of this compartment and their association with ciliates, which are restricted to this compartment and present an additional source of methanogenic substrates. IMPORTANCE Methane (CH4) is the second most important atmospheric greenhouse gas after CO2 and is believed to account for 17% of global warming. Methanogens are a diverse group of archaea and can be found in various anoxic habitats, including digestive tracts of plant-feeding animals. Termites, cockroaches, the larvae of scarab beetles, and millipedes are the only arthropods known to host methanogens and emit large amounts of methane. Millipedes are ranked as the third most important detritivores after termites and earthworms, and they are considered keystone species in many terrestrial ecosystems. Both methane-producing and non-methane-emitting species of millipedes have been observed, but what limits their methanogenic potential is not known. In the present study, we show that physicochemical gut conditions and the distribution of symbiotic ciliates are important factors determining CH4 emission in millipedes. We also found close similarities to other methane-emitting arthropods, which might be associated with their similar plant-feeding habits.

Macedomeris, a new monotypic doderiinine genus (Diplopoda, Glomerida) from a cave in North Macedonia, Balkan Peninsula.

Here we describe a new monotypic glomerid genus, Macedomeris gen. nov., with Macedomeris ivoi sp. nov. (a presumed troglobiont) as its type species. The new genus clearly differs from all other genera within the order Glomerida by the combination of several morphological characters: the presence of a characteristic deep lateral pit ("Ohrgrube") on both sides of the thoracic shield, the absence of striking ornamentation on tergites, the fusion of tergite 11 with the anal shield, and the lack of a large medial hump. In addition, Macedomeris gen. nov. differs from other members of the Glomerida by its general appearance, the presence of 2 or 3 vestigial ommatidia and a very wide syncoxite of a 2-segmented leg-pair 17 in the male. Notes on its ecology, troglomorphic features, and relationships with similar members of the tribe Doderiini are also given.