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The taxonomic identities of the two largely neglected Scolopendra Linnaeus, 1758 species from continental Spain, S.viridipes Dufour, 1820 and S.chlorotes L. Koch in Rosenhauer, 1856, are examined in this paper. After efforts in locating both species' type series in eight European institutions, the specimens are considered to be lost. Consequently, the identifications of both taxa were approximated by collating their descriptions with the morphology of all other sympatric Scolopendromorpha. Then, compatible topotypes for both species were collected, and among these a neotype for each taxon were selected and compared with the type series of their respective closest relatives. Finally, both S.viridipes and S.chlorotes are proposed to be conspecific with S.oraniensis Lucas, 1846. Therefore, the name S.viridipes is here established as (senior) syn. nov. and nomen oblitum of S.oraniensis, S.oraniensis is declared as nomen protectum, and S.chlorotes (junior) syn. nov. is reallocated to S.oraniensis. Moreover, the specimens making up the type series of S.oraniensis are also indicated and redescribed, the genitalia are illustrated for the first time, and its specific epithet is briefly reviewed, remaining unaltered in respect of its original spelling.

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BACKGROUND: Centipedes are terrestrial and predatory arthropods that possess an evolutionary transformed pair of appendages used for venom injection-the forcipules. Many arthropods incorporate reinforcing elements into the cuticle of their piercing or biting structures to enhance hardness, elasticity or resistance to wear and structural failure. Given their frequent exposure to high mechanical stress, we hypothesise that the cuticle of the centipede forcipule might be mechanically reinforced. With a combination of imaging, analytical techniques and mechanical testing, we explore the centipede forcipule in detail to shed light on its morphology and performance. Additionally, we compare these data to characteristics of the locomotory leg to infer evolutionary processes. RESULTS: We examined sclerotization patterns using confocal laser-scanning microscopy based on autofluorescence properties of the cuticle (forcipule and leg) and elemental composition by energy-dispersive X-ray spectroscopy in representative species from all five centipede lineages. These experiments revealed gradually increasing sclerotization towards the forcipular tarsungulum and a stronger sclerotization of joints in taxa with condensed podomeres. Depending on the species, calcium, zinc or chlorine are present with a higher concentration towards the distal tarsungulum. Interestingly, these characteristics are more or less mirrored in the locomotory leg's pretarsal claw in Epimorpha. To understand how incorporated elements affect mechanical properties, we tested resistance to structural failure, hardness (H) and Young's modulus (E) in two representative species, one with high zinc and one with high calcium content. Both species, however, exhibit similar properties and no differences in mechanical stress the forcipule can withstand. CONCLUSIONS: Our study reveals similarities in the material composition and properties of the forcipules in centipedes. The forcipules transformed from an elongated leg-like appearance into rigid piercing structures. Our data supports their serial homology to the locomotory leg and that the forcipule's tarsungulum is a fusion of tarsus and pretarsal claw. Calcium or zinc incorporation leads to comparable mechanical properties like in piercing structures of chelicerates and insects, but the elemental incorporation does not increase H and E in centipedes, suggesting that centipedes followed their own pathways in the evolutionary transformation of piercing tools.

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BACKGROUND: Evolution of novelty is a central theme in evolutionary biology, yet studying the origins of traits with an apparently discontinuous origin remains a major challenge. Venom systems are a well-suited model for the study of this phenomenon because they capture several aspects of novelty across multiple levels of biological complexity. However, while there is some knowledge on the evolution of individual toxins, not much is known about the evolution of venom systems as a whole. One way of shedding light on the evolution of new traits is to investigate less specialised serial homologues, i.e. repeated traits in an organism that share a developmental origin. This approach can be particularly informative in animals with repetitive body segments, such as centipedes. RESULTS: Here, we investigate morphological and biochemical aspects of the defensive telopodal glandular organs borne on the posterior legs of venomous stone centipedes (Lithobiomorpha), using a multimethod approach, including behavioural observations, comparative morphology, proteomics, comparative transcriptomics and molecular phylogenetics. We show that the anterior venom system and posterior telopodal defence system are functionally convergent serial homologues, where one (telopodal defence) represents a model for the putative early evolutionary state of the other (venom). Venom glands and telopodal glandular organs appear to have evolved from the same type of epidermal gland (four-cell recto-canal type) and while the telopodal defensive secretion shares a great degree of compositional overlap with centipede venoms in general, these similarities arose predominantly through convergent recruitment of distantly related toxin-like components. Both systems are composed of elements predisposed to functional innovation across levels of biological complexity that range from proteins to glands, demonstrating clear parallels between molecular and morphological traits in the properties that facilitate the evolution of novelty. CONCLUSIONS: The evolution of the lithobiomorph telopodal defence system provides indirect empirical support for the plausibility of the hypothesised evolutionary origin of the centipede venom system, which occurred through functional innovation and gradual specialisation of existing epidermal glands. Our results thus exemplify how continuous transformation and functional innovation can drive the apparent discontinuous emergence of novelties on higher levels of biological complexity.

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Chemical substances are of utmost importance for the biotic interactions between animals and their predators/parasites; many of these semiochemicals are emitted for defence purposes. One of the most deterrent and toxic biogenic substances we know of is hydrogen cyanide, which can be stored by certain insects, millipedes, centipedes and arachnids in the form of stable and less volatile molecules. The aim of this study was to analyse the biology and chemistry of such a defence mechanism in a geophilomorph centipede (Chilopoda). The cyanogenic secretion of Clinopodes flavidus is discharged from the ventral glands, whose glandular units are located in the space between the cuticle and the trunk muscles and do not extend deep into the segment. In addition to hydrogen cyanide, the ventral secretion contains 2-methylpentanoic acid, benzaldehyde, benzoyl cyanide, 2-methyl branched C-9 carboxylic acid (tentatively identified as 2-methyloctanoic acid), methyl 2-phenylacetate, benzoic acid and mandelonitrile as well as four major proteins with a molecular weight of 150, 66.2, 59 and 55 kDa. The correlation between the presence of ventral glands and guarding with the female's ventral side facing away from the eggs and young indicates a functional link between these two traits. We hope that the specificity of the chemical composition of the ventral secretion could serve as a criterion for chemotaxonomy and that the analysis of more species will help to clarify the phylogenetic relationships within the Geophilomorpha.

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Background: Centipedes of the family Geophilidae s.l. are widespread in the Holarctic, with the south-eastern part of the European Alps standing out as one of the most investigated regions. However, retrieving the published records for this taxon, even for this region, is challenging, since most of them are sparse in the specialised literature and interpreting them is hampered by the many taxonomic and nomenclatorial changes occurred in the past and recent times. New information: We assembled and released a dataset of occurrence records of the geophilid species in the south-eastern Alps, including all the published records and many other records present in unpublished catalogues of scientific collections. For each record, we integrated information from all the sources about: locality, date of collection, the taxonomic identifications, number and sex of individuals and available sequences of molecular markers. For all the records, we estimated geographic coordinates of the locality, when not originally provided, based on the information available. We also estimated the accuracy of the position.The dataset includes 3293 records referred to 39 species, obtained since the first half of the 19th century and up to 2022; 52% of these records have been released publicly for the first time in the dataset here described.

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Soil centipedes (Chilopoda, Geophilomorpha) are a widespread group of predators in the forest soils of the European Alps. While in the eastern and western parts of the Southern Prealps, larger efforts were devoted to sample and study the geophilomorph fauna, little is known about species richness and composition of geophilomorph communities in the central part of Southern Prealps. In this work, five sites located in the Val Camonica were surveyed by hand searching, between November 2021 and July 2022 and their species richness was estimated applying non-parametrical statistical methods (Chao-1 and Abundance-based Coverage Estimator) to account for incomplete detection. A total of 18 species were found amongst the five sites. A maximum of 12 species were recorded in each single site, while estimates suggest that another 1-3 species were likely undetected. Species composition were found highly variable also between sites with similar species richness.

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The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and glutathione S-transferase (GST), as well as the concentrations of sulfhydryl (SH) groups and glutathione (GSH) were analyzed in five age classes of the Mediterranean centipede Scolopendra cingulata as follows: embryo, adolescens, maturus junior, maturus, and maturus senior. The data obtained showed the presence of SOD, CAT, GSH-Px, GR, GST, and SH groups in embryos. The transition from embryo to adolescens was accompanied by an increase in the activities of all studied enzymes, in response to the increased production of ROS due to the increased metabolic activity of the centipede associated with growth and development. Our results show that trends in antioxidant enzyme (AOE) activities were not uniform among adult age classes, suggesting that maturus junior, maturus, and maturus senior differentially respond and/or have different susceptibility to ROS. On the other hand, GSH concentration in embryos was undetectable, highest in adolescens and decreased in the latter part of life. Pearson correlation analysis in embryos showed that the activities of the AOEs were strongly and positively correlated with each other but negatively correlated with GSH and SH groups. At later age classes, SOD, CAT, GSH-Px, GR, GSH, and SH groups were no longer significantly correlated with GST. In the discriminant analysis, the variables that separated the age classes were GR, GST, SH groups, and body length. Body length was directly related to the age of individuals, clearly indicating that development/aging affects the regulation of antioxidant defense in this species.

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Recent transcriptomic studies of myriapod phylogeny have been based on relatively small datasets with <40 myriapod terminals and variably supported or contradicted the traditional morphological groupings of Progoneata and Dignatha. Here we amassed a large dataset of 104 myriapod terminals, including multiple species for each of the four myriapod classes. Across the tree, most nodes are stable and well supported. Most analyses across a range of gene occupancy levels provide moderate to strong support for a deep split of Myriapoda into Symphyla + Pauropoda (=Edafopoda) and an uncontradicted grouping of Chilopoda + Diplopoda (=Pectinopoda nov.), as in other recent transcriptome-based analyses; no analysis recovers Progoneata or Dignatha as clades. As in all recent multi-locus and phylogenomic studies, chilopod interrelationships resolve with Craterostigmus excluded from Amalpighiata rather than uniting with other centipedes with maternal brood care in Phylactometria. Diplopod ordinal interrelationships are largely congruent with morphology-based classifications. Chilognathan clades that are not invariably advocated by morphologists include Glomerida + Glomeridesmida, such that the volvation-related characters of pill millipedes may be convergent, and Stemmiulida + Polydesmida more closely allied to Juliformia than to Callipodida + Chordeumatida. The latter relationship implies homoplasy in spinnerets and contradicts Nematophora. A time-tree with nodes calibrated by 25 myriapod and six outgroup fossil terminals recovers Cambrian-Ordovician divergences for the deepest splits in Myriapoda, Edafopoda and Pectinopoda, predating the terrestrial fossil record of myriapods as in other published chronograms, whereas age estimates within Chilopoda and Diplopoda overlap with or do not appreciably predate the calibration fossils. The grouping of Chilopoda and Diplopoda is recovered in all our analyses and is formalized as Pectinopoda nov., named for the shared presence of mandibular comb lamellae. New taxonomic proposals for Chilopoda based on uncontradicted clades are Tykhepoda nov. for the three blind families of Scolopendromorpha that share a "sieve-type" gizzard, and Taktikospina nov. for Scolopendromorpha to the exclusion of Mimopidae.

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BACKGROUND: Centipedes are one of the oldest terrestrial arthropods belonging to the sub phylum Myriapoda. With the expansion of our understanding of the application of the two centipedes Scolopendra morsitans and Scolopendra hainanum, belonging to the order Scolopendromorpha, an exhaustive classification was required. Although consensus has been reached on the phylogeny of Chilopoda based on morphological traits, recent analyses based on molecular data exhibited differences in results. METHODS AND RESULTS: The mitochondrial genome sequences of S. morsitans and S. hainanum were obtained by next-generation sequencing. S. morsitans contains 13 PCGs, two rRNAs, 11 tRNAs, and one CR. whereas S. hainanum contains 12 PCGs, of which ATP8 remains unpredicted, two rRNAs, 14 tRNAs, and one CR. An obvious tRNA rearrangement was found in the genus Scolopendra. S. morsitans exhibited a loss of trnW, trnC, trnI, trnK, trnD, trnA, trnN, trnQ, trnF, trnT, trnS, trnL, and trnV, and a repeat of trnR and trnL. S. hainanum exhibited a loss of trnQ, trnC, trnW, trnI, trnD, trnQ, trnP, and trnV. Phylogenetic analyses of centipedes based on 12 PCGs supported the sister relationship between the orders Geophilomorpha and Lithobiomorpha and a close relationship between Scolopendra dehaani and S. hainanum. CONCLUSIONS: The new mitogenomes determined in this study provide new genomic resources for gene rearrangements and contribute to the understanding of the evolution of gene rearrangement in Chilopoda.

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Background: At a time of immense human pressure on nature and the resulting global environmental changes, the inventory of biota - especially of undisturbed natural areas - is of unprecedented value as it provides a baseline for future research. Krokar, an example of such an undisturbed area, is the largest virgin forest remnant in Slovenia. It is located in the Dinaric Alps, which are believed to harbour the most diverse fauna of soil invertebrates in Europe. Nevertheless, the soil fauna of the Krokar virgin forest has not been thoroughly studied. Moreover, modern taxonomic approaches often rely on genetic information (e.g. DNA-barcodes), while extensive reference libraries from the Dinaric area are lacking. Our work, therefore, focused on addressing this lack of faunistic and genetic data from the Dinaric area. New information: A total of 2336 specimens belonging to 100 taxa (45 spiders, 30 centipedes, 25 ground-dwelling beetles) were collected and deposited to GBIF. DNA-barcodes of 124 specimens belonging to 73 species were successfully obtained and deposited in GenBank and BOLD databases.

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ABSTRACT Centipedes are venomous arthropods that have an elongated body, divided into many segments, presenting a pair of legs in each segment, adapted pairs of paws that simulate fangs and inject venom causing intense pain, with local erythema and edema, and rarely, blisters and skin necrosis. We present the case of a young woman pricked on her upper lip with intense swelling and local pain and discuss the real danger of envenomation and the therapeutic measures that should be taken.

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Among the Chilopoda class of centipede, the Cryptops genus is one of the most associated with envenomation in humans in the metropolitan region of the state of São Paulo. To date, there is no study in the literature about the toxins present in its venom. Thus, in this work, a transcriptomic characterization of the Cryptops iheringi venom gland, as well as a proteomic analysis of its venom, were performed to obtain a toxin profile of this species. These methods indicated that 57.9% of the sequences showed to be putative toxins unknown in public databases; among them, we pointed out a novel putative toxin named Cryptoxin-1. The recombinant form of this new toxin was able to promote edema in mice footpads with massive neutrophils infiltration, linking this toxin to envenomation symptoms observed in accidents with humans. Our findings may elucidate the role of this toxin in the venom, as well as the possibility to explore other proteins found in this work.

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BACKGROUND: The myriapod fauna of China is still poorly known and very little attention has been paid to the study of Lithobiomorpha, with only 100 species and subspecies known from the country. Altogether, 11 species of subgenusMonotarsobius have been recorded from China, but only two of them have been reported from Hebei Province. Herein, a new species recently discovered in the Hebei Province, China, is described and illustrated. NEW INFORMATION: A new lithobiids species Lithobius (Monotarsobius) tetrasulcus sp. n. is described and illustrated from Hengshui Lake National Nature Reserve, Hebei Province, China. The new species is compared with Lithobius (Monotarsobius) crassipes Koch, 1862 from Taiwan, China. It can be easily distinguished from congeners by having a longitudinal groove on the dorsal side of the femur and tibia of the male legs 14 and 15, only having a posterior spine on the dorsal side of femur of legs 12-15, lacking robust spines lying dorsally on the external margin on the second article of the female gonopods and the third article of the female gonopods having a bidentate apical claw.

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In Japan and Taiwan, five valid species of the genus Scolopendra Linnaeus, 1758 have been described: S. morsitans Linnaeus, 1758, S. subspinipes Leach, 1816, S. mutilans Koch, 1878, S. japonica Koch, 1878, and S. multidens Newport, 1844. Recently, an undetermined species was found in the Ryukyu Archipelago and Taiwan. Using molecular phylogenetic analyses with mitochondrial COI and 16S rRNA and nuclear 28S rRNA and 18S rRNA genes as well as conventional morphological examination, we successfully discriminated this sixth species as an independent lineage from S. subspinipes, S. mutilans, and other named congeners from East and Southeast Asia. Therefore, the species was described as S. alcyona Tsukamoto Shimano, sp. nov. Several situational evidences suggest that this species prefers streamside environments and exhibits amphibious behavior.

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OBJECTIVE: Centipede stings are a common problem in tropical countries. Current treatment guidelines do not include recommendations for antibiotic prophylaxis to prevent the associated bacterial infection since no previous study has assessed the effectiveness of antibiotic treatment in patients bitten by centipedes. Thus, this study aimed to compare the effectiveness of antibiotic prophylaxis over placebo for the skin infections that occur after a centipede sting. METHODS: In this randomized, double-blind, multi-center clinical trial conducted in the emergency departments in four hospitals, patients with any history of a centipede sting were prospectively enrolled and divided randomly into two groups. One group received dicloxacillin and the other a placebo. The primary outcome was the incidence of wound infection 3 to 5 days after the centipede sting. RESULTS: From December 2014 to October 2015, a total of 83 patients were enrolled in the study and were randomized into antibiotic (n=43) and placebo (n=40) groups. Two patients in the antibiotic group developed wound infections, while none showed wound infection in the placebo group (5% vs. 0%). The wound infection rate did not differ significantly between the two groups (P=0.496). CONCLUSION: Antibiotic prophylaxis may be unnecessary in cases of centipede stings. Proper wound care is an adequate and appropriate treatment for patients with centipede stings. However, the patient should be re-evaluated for detection of secondary bacterial infection.

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The tracheal system of scutigeromorph centipedes (Chilopoda) is special, as it consists of dorsally arranged unpaired spiracles. In this study, we investigate the tracheal systems of five different scutigeromorph species. They are strikingly similar to each other but depict unique characters compared to the tracheal systems of pleurostigmophoran centipedes, which has engendered an ongoing debate over a single versus independent origin of tracheal systems in Chilopoda. Up to now, only the respiratory system of Scutigera coleoptrata was investigated intensively using LM-, TEM-, and SEM-techniques. We supplement this with data for species from all three families of Scutigeromorpha. These reveal interspecific differences in atrial width and the shape and branching pattern of the tracheal tubules. Further, we investigated the tracheal system of Scutigera coleoptrata with three additional techniques: light sheet microscopy, microCT and synchrotron radiation based microCT analysis. This set of techniques allows a comparison between fresh versus fixed and dried material. The question of a unique vs. multiple origin of tracheal systems in centipedes and in Myriapoda as a whole is discussed with regard to their structural similarities and differences and the presence of hemocyanin as an oxygen carrier. We used morphological and molecular data and the fossil record to evaluate the alternative hypotheses.

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Among the Chilopoda class of centipede, the Cryptops genus is one of the most associated with envenomation in humans in the metropolitan region of the state of São Paulo. To date, there is no study in the literature about the toxins present in its venom. Thus, in this work, a transcriptomic characterization of the Cryptops iheringi venom gland, as well as a proteomic analysis of its venom, were performed to obtain a toxin profile of this species. These methods indicated that 57.9% of the sequences showed to be putative toxins unknown in public databases; among them, we pointed out a novel putative toxin named Cryptoxin-1. The recombinant form of this new toxin was able to promote edema in mice footpads with massive neutrophils infiltration, linking this toxin to envenomation symptoms observed in accidents with humans. Our findings may elucidate the role of this toxin in the venom, as well as the possibility to explore other proteins found in this work.

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BACKGROUND: The European North-East of Russia is the territory which includes the Nenets Autonomous District, represented by the East European tundra (from Kanin Peninsula to Vaigach Island), Komi Republic with its taiga ecosystems and the Urals (Northern, SubPolar and Polar). Over 20 years of systematic studies of soil fauna in the studied region has resulted in a huge amount of data being accumulated that can be analysed from different positions. Considering that the representation of Russian soil biota data, especially from European North-East of Russia in the GBIF database is not large, our data are of great interest to the scientific world community. The accumulation of such data will solve questions on national and global scales using large arrays.This study produced a dataset containing information on occurrences on soil invertebrates (Lumbricidae, Chilopoda, Diplopda, Collembola, Elateridae and Staphylinidae) in the European North-East of Russia. The dataset summarises occurrences noted in natural and disturbed forests, tundra and mountain ecosystems. NEW INFORMATION: Data from 196 geo-referenced localities of European North-East of Russia (tundra, taiga and mountains ecosystems) have been collated. A total of 5412 occurrences are included in the resource. The current project surveys 13 species of earthworms, 20 species of millipedes, 246 species of springtails, 446 species of rove beetles and 60 species of click beetles. The diversity of soil invertebrates in the European North-East of Russia has not been fully explored and further exploration will lead to more taxa.

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The present study describes a new Lithobiomorpha subgenus, Lithobius (Sinuispineus)subgen. nov., and two new species, L. (Sinuispineus) sinuispineussp. nov. and L. (Sinuispineus) minuticornissp. nov. from China. The representatives of the new subgenus are characterized by a considerable sexual dimorphism of the ultimate leg pair 15, having the femur and tibia unusually enlarged in males, and the dorsal side of the femur with curved posterior spurs. These features distinguish Lithobius (Sinuispineus)subgen. nov. from all other subgenera of Lithobius. The diagnosis and the main morphological characters of the new subgenus and of the two new species are given for both male and female specimens.

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The type material of Sogona cyclareata Attems, 1947 is revised. The syntype shares characters with representatives of the family Schendylidae and not the Geophilidae to which it is currently assigned. The species has the claw of the second maxillae pectinate and the labrum not divided into median and lateral portions. Sogona cyclareata presents also characters of the genus Schendylops Cook, 1899 such as the presence of two pores in each coxopleuron, ultimate legs without claws, and the arrangement of the sternal pores-fields. No Schendylops species known to date has the characters of S. cyclareata, so we propose the new combination Schendylops cyclareatus.

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