Subcortical life, evolution of flattened body, and constrained mating posture in the earwig Platylabia major (Insecta: Dermaptera: "Anisolabididae").

Many animals take advantage of the shaded, humid, and protected environments in subcortical spaces, i.e., thin spaces under the loosened bark of dead trees. Permanent inhabitants of subcortical spaces often show specialized morphologies, such as a miniaturized or dorsoventrally flattened body. However, the evolutionary consequences of these specialized morphologies on behavioral, ecological, and life-history traits have been little studied. We studied the mating biology and anatomy of Platylabia major (usually placed in the family Anisolabididae), which is an obligate inhabitant of subcortical spaces with a paper-like flattened body, and compared them with those of two thicker, spongiphorid earwigs, Nesogaster amoenus and Paralabellula curvicauda. Mating trials in various settings showed that Pl. major requires thin spaces sandwiched by two planes to accomplish genital coupling and insemination. In contrast, the thicker species, although also frequently found in subcortical spaces, could mate on a single horizontal plane due to the ability of the male to twist its abdomen through approximately 180°. Examination by micro-computed tomography and a reagent-based clearing technique revealed no substantive differences in the configuration of mid-abdominal musculature between the species. The dorsal and lateral muscles of Pl. major, which are almost parallel to the antero-posterior body axis for accommodation within the thin abdomen, seemed incapable of producing the power to twist the abdomen. The abdominal musculature conforms to a simple pattern in both male and female earwigs, which is repeated in each of the pregenital segments. We conclude that small differences in the range of motion of each abdominal segment can result in large differences in possible mating postures and positions. Surgical experiments also demonstrated that both right and left penises of Pl. major are competent and used for insemination with no lateral bias, as in most other earwigs with twin penises studied to date.

Sperm models in European Plecoptera.

Systematic issues regarding Plecoptera are still debated, and the molecular data seem to be unable to definitively clarify the relationships within the order. Spermatozoa are under constant evolutionary pressure, and comparative spermatology can be useful in carrying systematic and phylogenetic information. In the present paper we describe the sperm structure, using light, scanning and transmission electron and immunofluorescence microscopy, of six Euholognatha species belonging to genera not analyzed in our previous studies, i.e. Capnopsis, Amphinemura, Rhabdiopteryx, Tyrrhenoleuctra, Zwicknia and Protonemura. The spermatozoa of all the species examined are fîliform and have a flagellum characterized by an axoneme with 9 + 9+2 pattern and two mitochondrial derivatives. Their ultrastructure shows a degree of heterogeneity within the order. On the contrary, morphological features of sperm are well conserved inside a single Euholognathan family, and the species share a general family sperm model, even if different interspecific or intergeneric characters can be identified and used for systematic inferences. Among Nemouroidea, Taeniopterygidae, showing a peculiar sperm model, seems to have an isolated phylogenetic position. Nemouridae, with a mono-layered acrosome, are isolated among the remaining families, while we can hypothesize a sister taxa relationship between Leuctridae and Capniidae. As regards Perloidea, the sperm characters suggest a closer relationship between Chloroperlidae and Perlodidae, rather than between Perlidae and Perlodidae, as commonly hypothesized.

Promising application of probiotic microorganisms as Pickering emulsions stabilizers.

The purpose of this work was to study the ability of nineteen food-grade microorganisms as Pickering emulsion (PE) stabilizers. Medium-chain triacylglycerol (MCT) oil-in-water (50:50) PEs were fabricated by 10 wt% or 15 wt% of thermally-inactivated yeast, cocci, Bacillus spp. and lactobacilli cells. The characteristics of microorganisms related to "Pickering stabilization" including morphology, surface charge, interfacial tension, and "contact angle" were firstly studied. After that, the cells-stabilized PEs were characterized from both kinetic and thermodynamic viewpoints, microstructure and rheological properties. The interfacial tension and "contact angle" values of various microorganisms ranged from 16.33 to 38.31 mN/m, and from 15° to 106°, respectively. The mean droplet size of PEs ranged from 11.51 to 57.69 µm. Generally, the physical stability of cell-stabilized PEs followed this order: lactobacilli > Bacillus spp. > cocci > yeast. These variations were attributed to the morphology and cell wall composition. Increasing the microorganism concentration significantly increased the physical stability of PEs from a maximum of 12 days at 10 wt% to 35 days at 15 wt% as a result of better interface coverage. Shear-thinning and dominant elastic behaviors were observed in PEs. Physical stability was affected by the free energy of detachment. Therefore, food-grade microorganisms are suggested for stabilizing PEs.

Efficient symptomatic treatment and viral load reduction for children with influenza virus infection by nasal-spraying Bacillus spore probiotics.

Influenza virus is a main cause of acute respiratory tract infections (ARTIs) in children. This is the first double-blind, randomized, and controlled clinical trial examining the efficacy of nasal-spraying probiotic LiveSpo Navax, which contains 5 billion of Bacillus subtilis and B. clausii spores in 5 mL, in supporting treatment of influenza viral infection in pediatric patients. We found that the nasal-spraying Bacillus spores significantly shortened the recovery period and overall treatment by 2 days and increased treatment effectiveness by 58% in resolving all ARTIs' symptoms. At day 2, the concentrations of influenza virus and co-infected bacteria were reduced by 417 and 1152 folds. Additionally, the levels of pro-inflammatory cytokines IL-8, TNF-α, and IL-6 in nasopharyngeal samples were reduced by 1.1, 3.7, and 53.9 folds, respectively. Compared to the standard control group, treatment regimen with LiveSpo Navax demonstrated significantly greater effectiveness, resulting in 26-fold reduction in viral load, 65-fold reduction in bacterial concentration, and 1.1-9.5-fold decrease in cytokine levels. Overall, nasal-spraying Bacillus spores can support the symptomatic treatment of influenza virus-induced ARTIs quickly, efficiently and could be used as a cost-effective supportive treatment for respiratory viral infection in general.Clinical trial registration no: NCT05378022 on 17/05/2022.

Isoperla riverae, a new stonefly species from the southeast Nearctic, with notes on sympatric species including the larval description of Isoperla lenati Szczytko & Kondratieff, 2015 (Plecoptera: Perlodidae).

Isoperla riverae sp. n. is described from the southeastern USA. The new species is proposed based on details of the adult habitus, male aedeagus, vesicle, female subgenital plate, ovum chorion, and larval habitus. Supporting data includes color images, scanning electron micrographs, genetic analysis of DNA barcodes, and comparative morphology of cognate species. The larva of Isoperla lenati Szczytko & Kondratieff, 2015 is also described supported by color images.

Revision of the African Neoperla Needham, 1905 (Plecoptera: Perlidae: Perlinae) based on morphological and molecular data.

Adults of the African species of the genus Neoperla Needham, 1905 (Plecoptera: Perlidae: Perlinae) are revised, and 82 valid species are recognised. Of the original 29 named species, 14 valid ones are redescribed from types, nine lectotypes are designated, and nine new synonymies are proposed. Sixty-two new species are named, and several additional new species only known from material insufficient for formal description are listed. There are one unavailable nomen nudum and three doubtful names. Diagnostic morphological traits of the recognised species are described and illustrated in detail where available of males, females, and eggs. Dichotomous keys to all species are provided. Mitochondrial DNA-data of 71 species-group taxa are available, which permits reliable association of sexes and minimises the risk of synonymies between species known from only one sex. Importantly, this includes DNA sequences from 50 holotypes. The DNA-data will also permit future monitoring with eDNA sequencing and identification of nymphs, which are probably important but so far unidentifiable bioindicators in streams. The genus Neoperla occurs largely in the northern hemisphere and in Africa, where it is restricted to the Ethiopian region south of the Sahara but unknown from Madagascar. A single specimen not clearly distinct from a widespread mainland species was taken on Comoro Island. All African species are endemic, but one African species group has a few outlying members in Asia. The Asian N. montivaga-group is not known from Africa. The following new species are described and named: N. aethiopica n. sp., N. amoena n. sp., N. angolana n. sp., N. bareensis n. sp., N. bella n. sp., N. benti n. sp., N. beta n. sp., N. bipolaris n. sp., N. biserrata n. sp., N. brachyphallus n. sp., N. caeleps n. sp., N. cataractae n. sp., N. claviger n. sp., N. coffea n. sp., N. costata n. sp., N. crenulata n. sp., N. crustata n. sp., N. decorata n. sp., N. dianae n. sp., N. dolium n. sp., N. dundoana n. sp., N. duodeviginti n. sp., N. erinaceus n. sp., N. excavata n. sp., N. filamentosa n. sp., N. funiculata n. sp., N. gibbosa n. sp., N. gordius n. sp., N. heideae n. sp., N. ivanloebli n. sp., N. juxtadidita n. sp., N. kalengonis n. sp., N. larvata n. sp., N. lineata n. sp., N. luhohonis n. sp., N. massevensis n. sp., N. multiserrata n. sp., N. muyukae n. sp., N. nichollsi n. sp., N. occulta n. sp., N. orthonema n. sp., N. pallidogigas n. sp., N. panafricana n. sp., N. pickeri n. sp., N. pilulifera n. sp., N. pirus n. sp., N. planidorsum n. sp., N. plicata n. sp., N. proxima n. sp., N. pusilla n. sp., N. rostrata n. sp., N. sambarua n. sp., N. sassandrae n. sp., N. schuelei n. sp., N. serrula n. sp., N. simplex n. sp., N. socia n. sp., N. sorella n. sp., N. spaghetti n. sp., N. spectabilis n. sp., N. spironema n. sp., N. tangana n. sp., N. tansanica n. sp., N. usambara n. sp., and N. vicina n. sp..

Revision of the Neotropical stick insect genus Ocnophila (Phasmatodea: Diapheromeridae) with a new species from Colombia.

The genus Ocnophila Brunner, 1907 is here redescribed with an emended diagnosis, containing three valid species from Venezuela and Colombia: Ocnophila integra Brunner, 1907 with Ocnophila signatior Brunner, 1907 syn. nov. as a new junior synonym, Ocnophila iphicla (Westwood, 1859) and Ocnophila serrata sp. nov. In addition to the description of the new species we redescribe O. integra and O. iphicla, also providing a description of the male genitalia for O. integra. For the other species previously contained in the genus, we synonymize Ocnophila brevifemur Brunner, 1907 syn. nov. and Ocnophila armata Brunner, 1907 syn. nov. under Pygirhynchus bispinosus (Redtenbacher, 1906), Ocnophila inaequalis Brunner, 1907 syn. nov. under Libethra venezuelica Brunner, 1907, and transfer the remaining species to other genera, resulting in the following new combinations: Agamemnon illegitimus (Brunner, 1907) comb. nov., A. poeyi (Bolívar, 1888) comb. nov., Canuleius nattereri (Brunner, 1907) comb. nov., C. pedestris (Brunner, 1907) comb. nov., Dyme acanthonota (Günther, 1930) comb. nov., D. borellii (Giglio-Tos, 1898) comb. nov., D. ramulus (Giglio-Tos, 1898) comb. nov., Exocnophila cornuta (Brunner, 1907) comb. nov., E. tuberculata (Brunner, 1907) comb. nov., Litosermyle inconspicua (Brunner, 1907) comb. nov., Lit. nana (Shelford, 1913) comb. nov., Lit. riveti (Shelford, 1913) comb. nov., Lit. submutica (Brunner, 1907) comb. nov., Libethra aculeata (Brunner, 1907) comb. nov., Libethroidea willemsei (Günther, 1935) comb. nov., Pygirhynchus fortior (Brunner, 1907) comb. nov., P. oryx (Westwood, 1859) comb. nov., P. scops (Kaup, 1871) comb. nov., Pseudosermyle meditans (Brunner, 1907) comb. nov., Sermyle aurita (Rehn, 1905) comb. nov., and S. ciliata (Brunner, 1907) comb. nov. Furthermore, Pygirhynchus carioca Piza, 1944 syn. nov. is synonymized under P. fortior comb. nov. We provide a description of the male and egg of Litosermyle Hebard, 1919, previously known only from females, through the illustration and redescription of Lit. inconspicua (Brunner, 1907) comb. nov. Finally, we include Dubiophasma Zompro, 2001, Exocnophila Zompro, 2001, Litosermyle, Ocnophila and Parocnophila Zompro, 1998 in Oreophoetini.

The Nemourinae (Insecta, Nemouridae) of the eastern Nearctic.

Morphology-based concepts of the 26 eastern Nearctic species of the subfamily Nemourinae (Insecta, Nemouridae) Billberg, 1820 are reviewed. Nemourinae is represented in this region by Nemoura Latrielle, 1796, Ostrocerca Ricker, 1952, Paranemoura Needham & Claassen, 1925, Podmosta Ricker, 1952, Prostoia Ricker, 1952, Shipsa Ricker, 1952, Soyedina Ricker, 1952, and Zapada Ricker, 1952. Wing venation and patterns of mottling are depicted with standard light microscopy. Diagnostic external reproductive structures are emphasized with line drawings, scanning electron microscopy, and standard light microscopy. A genus-level key to male and female adults is included. Species-level keys for Ostrocerca, Paranemoura, Prostoia, Soyedina, and Zapada are also provided.

The types of Phasmatodea (= Phasmida) deposited in the Eidgenössisches Technisches Hochschulzentrum, Zürich, Switzerland (ETHZ).

Type specimens of 42 taxa of Phasmatodea (including probable type specimens of 14 taxa) have been located in the Eidgenössisches Technisches Hochschulzentrum, Zürich. The species are listed alphabetically, with the number of specimens, sex and locality data. Some minor taxonomic changes are proposed: 1 new combination, 1 revised combination, 2 lectotype designations.

Notes on Leuctra signifera Kempny, 1899 and Leuctra austriaca Aubert, 1954 (Plecoptera: Leuctridae), with the description of a new species.

Leuctra signifera Kempny, 1899 and Leuctra austriaca Aubert, 1954 are re-described and their taxonomical status is discussed. New country records are reported for L. austriaca from Hungary and L. signifera from Italy, Slovenia, and Hungary. A new species, Leuctra papukensis sp. n., from Croatia, is described and illustrated. The subspecies Leuctra signifera jahorinensis Kacanski, 1972 is raised to species level.

ebony underpins Batesian mimicry in melanic stoneflies.

The evolution of Batesian mimicry - whereby harmless species avoid predation through their resemblance to harmful species - has long intrigued biologists. In rare cases, Batesian mimicry is linked to intraspecific colour variation, in which only some individuals within a population resemble a noxious 'model'. Here, we assess intraspecific colour variation within a widespread New Zealand stonefly, wherein highly melanized individuals of Zelandoperla closely resemble a chemically defended aposematic stonefly, Austroperla cyrene. We assess convergence in the colour pattern of these two species, compare their relative palatability to predators, and use genome-wide association mapping to assess the genetic basis of this resemblance. Our analysis reveals that melanized Zelandoperla overlap significantly with Austroperla in colour space but are significantly more palatable to predators, implying that they are indeed Batesian mimics. Analysis of 194,773 genome-wide SNPs reveals an outlier locus (ebony) strongly differentiating melanic versus non-melanic Zelandoperla. Genotyping of 338 specimens from a single Zelandoperla population indicates that ebony explains nearly 70% of the observed variance in melanism. As ebony has a well-documented role in insect melanin biosynthesis, our findings indicate this locus has a conserved function across deeply divergent hexapod lineages. Distributional records suggest a link between the occurrence of melanic Zelandoperla and the forested ecosystems where the model Austroperla is abundant, suggesting the potential for adaptive shifts in this system underpinned by environmental change.

Are males just passive? Coupling mechanism of the Brazilian cave insects with inverted genitalia.

Species of the Brazilian cave barklouse genus Neotrogla (Psocodea: "Psocoptera": Trogiomorpha: Prionoglarididae: Sensitibillini) are known to have a "female penis (gynosome)" that functions as an intromittent organ inserted into the membranous pouches in the simple male genital chamber during copulation to receive semen. However, the functions of other male and female genital structures and the copulatory processes of Neotrogla were completely unknown to date. Based on µCT observation of the male and female postabdomen and connected muscles both before and in copula, we clarified the functions of the male and female genital structures. In addition, based on the analyses of the established 3D models, we concluded that precise and rigid contact of multiple genital structures, and step-by-step releases of each holding mechanism achieved by the cooperation of both sexes are involved in the copulatory processes. The coevolution between the male and female genital structures in Neotrogla may provide a new example for the evolution of tolerance traits.

Complex evolutionary processes maintain an ancient chromosomal inversion.

Genome re-arrangements such as chromosomal inversions are often involved in adaptation. As such, they experience natural selection, which can erode genetic variation. Thus, whether and how inversions can remain polymorphic for extended periods of time remains debated. Here we combine genomics, experiments, and evolutionary modeling to elucidate the processes maintaining an inversion polymorphism associated with the use of a challenging host plant (Redwood trees) in Timema stick insects. We show that the inversion is maintained by a combination of processes, finding roles for life-history trade-offs, heterozygote advantage, local adaptation to different hosts, and gene flow. We use models to show how such multi-layered regimes of balancing selection and gene flow provide resilience to help buffer populations against the loss of genetic variation, maintaining the potential for future evolution. We further show that the inversion polymorphism has persisted for millions of years and is not a result of recent introgression. We thus find that rather than being a nuisance, the complex interplay of evolutionary processes provides a mechanism for the long-term maintenance of genetic variation.

The neuronal innervation pattern of the subgenual organ complex in Peruphasma schultei (Insecta: Phasmatodea).

The proximal tibia of orthopteroid insects contains sensory organs, the subgenual organ complex, detecting mechanical stimuli including substrate vibration. In stick insects, two chordotonal organs occur in close proximity, the subgenual organ and the distal organ, which likely detect substrate vibrations. In most stick insects, both organs are innervated by separate nerve branches. To obtain more data on the neuroanatomy of the subgenual organ complex from the New World phasmids (Occidophasmata), the present study documents the neuronal innervation of sensory organs in the subgenual organ complex of Peruphasma schultei, the first species from Pseudophasmatinae investigated for this sensory complex. The innervation pattern shows a distinct nerve branch for the subgenual organ and for the distal organ in most cases. Some variability in the innervation, which generally occurs for these chordotonal organs, was noted for both organs in P. schultei. The most common innervation for both organs was by a single nerve branch for each organ. The innervation of the subgenual organ resembled the nerve pattern of another New World phasmid, but was simpler than in the Old World phasmids (Oriophasmata) studied so far. Therefore, the peripheral neuronal innervation of sensory organs could reflect phylogenetic relationships and provide phylogenetic information, while the overall neuroanatomy of the subgenual organ complex is similar in stick insects.

Anatomical, phenological and genetic aspects of the host-parasite relationship between Andrena vaga (Hymenoptera) and Stylops ater (Strepsiptera).

Stylops ater is an endoparasite of the mining bee Andrena vaga with extreme sexual dimorphism and hypermetamorphosis. Its population structure, parasitization mode, genetic diversity and impact on host morphology were examined in nesting sites in Germany to better understand this highly specialized host­parasite interaction. The shift in host emergence due to stylopization was proven to be especially strong in A. vaga. Around 10% of bees hosted more than 1 Stylops, with at maximum 4. A trend in Stylops' preference for hosts of their own sex and a sex-specific position of extrusion from the host abdomen was found. Invasion of Andrena eggs by Stylops primary larvae was depicted for the first time. Cephalothoraces of female Stylops were smaller in male and pluristylopized hosts, likely due to lower nutrient supply. The genes H3, 18S and cytochrome c oxidase subunit 1 were highly conserved, revealing near-absence of local variation within Stylops. Ovaries of hosts with male Stylops contained poorly developed eggs while those of hosts with female Stylops were devoid of visible eggs, which might be due to a higher protein demand of female Stylops. Male Stylops, which might have a more energy-consuming development, led to a reduction in head width of their hosts. Host masculinization was present in the leaner shape of the metabasitarsus of stylopized females and is interpreted as a by-product of manipulation of the host's endocrine system to shift its emergence. Stylopization intensified tergal hairiness, most strongly in hosts with female Stylops, near the point of parasite extrusion, hinting towards substance-induced host manipulation.

Leaves that walk and eggs that stick: comparative functional morphology and evolution of the adhesive system of leaf insect eggs (Phasmatodea: Phylliidae).

Phylliidae are herbivorous insects exhibiting impressive cryptic masquerade and are colloquially called "walking leaves". They imitate angiosperm leaves and their eggs often resemble plant seeds structurally and in some cases functionally. Despite overall morphological similarity of adult Phylliidae, their eggs reveal a significant diversity in overall shape and exochorionic surface features. Previous studies have shown that the eggs of most Phylliidae possess a specialised attachment mechanism with hierarchical exochorionic fan-like structures (pinnae), which are mantled by a film of an adhesive secretion (glue). The folded pinnae and glue respond to water contact, with the fibrous pinnae expanding and the glue being capable of reversible liquefaction. In general, the eggs of phylliids appear to exhibit varying structures that were suggested to represent specific adaptations to the different environments the eggs are deposited in. Here, we investigated the diversity of phylliid eggs and the functional morphology of their exochorionic structure. Based on the examination of all phylliid taxa for which the eggs are known, we were able to characterise eleven different morphological types. We explored the adhesiveness of these different egg morphotypes and experimentally compared the attachment performance on a broad range of substrates with different surface roughness, surface chemistry and tested whether the adhesion is replicable after detachment in multiple cycles. Furthermore, we used molecular phylogenetic methods to reconstruct the evolutionary history of different egg types and their adhesive systems within this lineage, based on 53 phylliid taxa. Our results suggest that the egg morphology is congruent with the phylogenetic relationships within Phylliidae. The morphological differences are likely caused by adaptations to the specific environmental requirements for the particular clades, as the egg morphology has an influence on the performance regarding the surface roughness. Furthermore, we show that different pinnae and the adhesive glue evolved convergently in different species. While the evolution of the Phylliidae in general appears to be non-adaptive judging on the strong similarity of the adults and nymphs of most species, the eggs represent a stage with complex and rather diverse functional adaptations including mechanisms for both fixation and dispersal of the eggs.

A new genus and species of Perlodinae (Plecoptera: Perlodidae) from Korea.

Habaek koreanus gen. n., sp. n., a remarkable new Perlodinae is described from adults of both sexes, collected by Malaise traps in South Korea. On the basis of male characters, it is assigned to the tribe Perlodini, but its tribal classification needs to be clarified by characters of the larva and matured eggs. Affinities of the new genus are discussed, and a key is presented for the males of the Perlodini genera.

The unique C-mannosylated hypertrehalosemic hormone of Carausius morosus: Identity, release, and biological activity.

Previous studies had shown that the corpora cardiaca (CC) of the Indian stick insect, Carausius morosus, synthesizes two hypertrehalosemic hormones (HrTHs)-decapeptides which differ in the way that the chromatographically less-hydrophobic form, code-named Carmo-HrTH-I, is modified by an unique C-mannosylated tryptophan residue at position 8. The availability of milligram amounts of this modified peptide in synthetic form now makes it possible to study physico-chemical and physiological properties. This study revealed that the synthetic peptide co-elutes with the natural peptide from the CC chromatographically, is heat stable for at least 30 min at 100°C, and causes hyperlipemia in acceptor locusts (a heterologous bioassay) and hypertrehalosemia in ligated stick insects (conspecific bioassay). In vitro incubation of Carmo-HrTH-I together with stick insect hemolymph (a natural source of peptidases) demonstrated clearly via chromatographic separation that the C-mannosylated Trp bond is stable and is not broken down to Carmo-HrTH-II (the more-hydrophobic decapeptide with an unmodified Trp residue). This notwithstanding, breakdown of Carmo-HrTH-I did take place, and the half-life of the compound was calculated as about 5 min. Finally, the natural peptide is releasable when CC are treated in vitro with a depolarizing saline (high potassium concentration) suggesting its role as true HrTHs in the stick insect. In conclusion, the results indicate that Carmo-HrTH-I which is synthesized in the CC is released into the hemolymph, binds to a HrTH receptor in the fat body, activates the carbohydrate metabolism pathway and is quickly inactivated in the hemolymph by (an) as yet unknown peptidase(s).

The intraspecific morphological variability of Styloperla Wu, 1935 (Plecoptera: Styloperlidae).

Intraspecific morphological variability of four Styloperla Wu, 1935 species are described and discussed in this paper. The males of each species have variable specializations present at their basal cercal process, including the variable number of branches or differing degrees of curvature at the apical spines. A generalization on the species definition of Plecoptera, especially a new concept of conspecificity is also provided herein.