Search

Background: In evolutionary biology, identifying and quantifying inter-lineage genome size variation and elucidating the underlying causes of that variation have long been goals. Repetitive elements (REs) have been proposed and confirmed as being among the most important contributors to genome size variation. However, the evolutionary implications of genome size variation and RE dynamics are not well understood. Results: A total of 35 Ensifera insects were collected from different areas in China, including nine species of crickets and 26 species of katydids. The genome sizes of seven species were then determined using flow cytometry. The RepeatExplorer2 pipeline was employed to retrieve the repeated sequences for each species, based on low-coverage (0.1 X) high-throughput Illumina unassembled short reads. The genome sizes of the 35 Ensifera insects exhibited a considerable degree of variation, ranging from 1.00 to 18.34 pg. This variation was more than 18-fold. Similarly, the RE abundances exhibited considerable variation, ranging from 13.66 to 61.16%. In addition, the Tettigonioidea had larger genomes and contained significantly more REs than did the Grylloidea genomes. Analysis of the correlation between RE abundance and the genome size of 35 Ensifera insects revealed that the abundance of REs, transposable elements (TEs), long terminal repeats (LTRs), and long interspersed nuclear elements (LINEs) are significantly correlated with genome size. Notably, there is an inflection point in this correlation, where species with increasingly large genomes (e.g., > 5–10 pg) have repeats that contribute less to genome expansion than expected. Furthermore, this study revealed contrasting evolutionary directions between the Tettigonioidea and Grylloidea clades in terms of the expansion of REs. Tettigonioidea species exhibit a gradual increase in ancestral genome size and RE abundance as they diverge, while Grylloidea species experience sustained genome contraction. Conclusions: This study reveals extensive variation in genome size and RE abundance in Ensifera insects, with distinct evolutionary patterns across two major groups, Tettigonioidea and Grylloidea. This provides valuable insights into the variation in genome size and RE abundance in Ensifera insects, offering a comprehensive understanding of their evolutionary history. [ABSTRACT FROM AUTHOR]

Abstract Background In evolutionary biology, identifying and quantifying inter-lineage genome size variation and elucidating the underlying causes of that variation have long been goals. Repetitive elements (REs) have been proposed and confirmed as being among the most important contributors to genome size variation. However, the evolutionary implications of genome size variation and RE dynamics are not well understood. Results A total of 35 Ensifera insects were collected from different areas in China, including nine species of crickets and 26 species of katydids. The genome sizes of seven species were then determined using flow cytometry. The RepeatExplorer2 pipeline was employed to retrieve the repeated sequences for each species, based on low-coverage (0.1 X) high-throughput Illumina unassembled short reads. The genome sizes of the 35 Ensifera insects exhibited a considerable degree of variation, ranging from 1.00 to 18.34 pg. This variation was more than 18-fold. Similarly, the RE abundances exhibited considerable variation, ranging from 13.66 to 61.16%. In addition, the Tettigonioidea had larger genomes and contained significantly more REs than did the Grylloidea genomes. Analysis of the correlation between RE abundance and the genome size of 35 Ensifera insects revealed that the abundance of REs, transposable elements (TEs), long terminal repeats (LTRs), and long interspersed nuclear elements (LINEs) are significantly correlated with genome size. Notably, there is an inflection point in this correlation, where species with increasingly large genomes (e.g., > 5–10 pg) have repeats that contribute less to genome expansion than expected. Furthermore, this study revealed contrasting evolutionary directions between the Tettigonioidea and Grylloidea clades in terms of the expansion of REs. Tettigonioidea species exhibit a gradual increase in ancestral genome size and RE abundance as they diverge, while Grylloidea species experience sustained genome contraction. Conclusions This study reveals extensive variation in genome size and RE abundance in Ensifera insects, with distinct evolutionary patterns across two major groups, Tettigonioidea and Grylloidea. This provides valuable insights into the variation in genome size and RE abundance in Ensifera insects, offering a comprehensive understanding of their evolutionary history.

Stridulation is used by male katydids to produce sound via the rubbing together of their specialised forewings, either by sustained or interrupted sweeps of the file producing different tones and call structures. There are many species of Orthoptera that remain undescribed and their acoustic signals are unknown. This study aims to measure and quantify the mechanics of wing vibration, sound production and acoustic properties of the hearing system in a new genus of Pseudophyllinae with taxonomic descriptions of two new species. The calling behaviour and wing mechanics of males were measured using micro-scanning laser Doppler vibrometry, microscopy, and ultrasound sensitive equipment. The resonant properties of the acoustic pinnae of the ears were obtained via μ-CT scanning and 3D printed experimentation, and numerical modelling was used to validate the results. Analysis of sound recordings and wing vibrations revealed that the stridulatory areas of the right tegmen exhibit relatively narrow frequency responses and produce narrowband calls between 12 and 20 kHz. As in most Pseudophyllinae, only the right mirror is activated for sound production. The acoustic pinnae of all species were found to provide a broadband increased acoustic gain from ~40–120 kHz by up to 25 dB, peaking at almost 90 kHz which coincides with the echolocation frequency of sympatric bats. The new genus, named Satizabalus n. gen., is here derived as a new polytypic genus from the existing genus Gnathoclita, based on morphological and acoustic evidence from one described (S. sodalis n. comb.) and two new species (S. jorgevargasi n. sp. and S. hauca n. sp.). Unlike most Tettigoniidae, Satizabalus exhibits a particular form of sexual dimorphism whereby the heads and mandibles of the males are greatly enlarged compared to the females. We suggest that Satizabalus is related to the genus Trichotettix, also found in cloud forests in Colombia, and not to Gnathoclita. [ABSTRACT FROM AUTHOR]

Stridulation is used by male katydids to produce sound via the rubbing together of their specialised forewings, either by sustained or interrupted sweeps of the file producing different tones and call structures. There are many species of Orthoptera that remain undescribed and their acoustic signals are unknown. This study aims to measure and quantify the mechanics of wing vibration, sound production and acoustic properties of the hearing system in a new genus of Pseudophyllinae with taxonomic descriptions of two new species. The calling behaviour and wing mechanics of males were measured using micro-scanning laser Doppler vibrometry, microscopy, and ultrasound sensitive equipment. The resonant properties of the acoustic pinnae of the ears were obtained via μ-CT scanning and 3D printed experimentation, and numerical modelling was used to validate the results. Analysis of sound recordings and wing vibrations revealed that the stridulatory areas of the right tegmen exhibit relatively narrow frequency responses and produce narrowband calls between 12 and 20 kHz. As in most Pseudophyllinae, only the right mirror is activated for sound production. The acoustic pinnae of all species were found to provide a broadband increased acoustic gain from ~40–120 kHz by up to 25 dB, peaking at almost 90 kHz which coincides with the echolocation frequency of sympatric bats. The new genus, named Satizabalus n. gen., is here derived as a new polytypic genus from the existing genus Gnathoclita, based on morphological and acoustic evidence from one described (S. sodalis n. comb.) and two new species (S. jorgevargasi n. sp. and S. hauca n. sp.). Unlike most Tettigoniidae, Satizabalus exhibits a particular form of sexual dimorphism whereby the heads and mandibles of the males are greatly enlarged compared to the females. We suggest that Satizabalus is related to the genus Trichotettix, also found in cloud forests in Colombia, and not to Gnathoclita.

An updated checklist of the order Orthoptera of Kerala is provided. Eighty-five species have been added to the existing checklist. A total of 215 species and 21 subspecies belonging to 154 genera under 18 families of two suborders are enumerated along with their distributional data across the state. Suborders Caelifera and Ensifera are represented by 127 and 88 species, respectively. © 2023 Association for Advancement of Entomology. [ABSTRACT FROM AUTHOR]

Morphological sexual dimorphism occurs in most insect species. Caves are relatively independent habitats with high levels of endemic insect species. The cave crickets are one of the most common insects in many caves and play an important role in the nutrient cycling of cave ecosystems. Sexual difference in sensilla has rarely been studied in cave crickets. We explore the types, number, and distribution of sensilla on the labial palps of both sexes of the cave cricket Tachycines plumiopedella Li, Feng & Luo, 2021 for the first time. Seven sensilla types were recorded on the labial palps in both sexes, including sensilla chaetica (Sc. 1–2), sensilla trichodea (St. 1–3), sensilla palmatum (Sp), Böhm bristles (Bb), sensilla campaniformia (Sca), sensilla basiconica (Sb. 1–3), and sensilla coeloconica (Sco. 1–2). The sensilla are mostly situated on the third palpomere of the labial palps, particularly on its middle to end part. Of sensilla on the labial palps, types and distribution were similar in males and females, but different in length, diameter, and number. The potential functional roles of sensilla were discussed. [ABSTRACT FROM AUTHOR]

Fossils are more and more used in phylogenetic evolutionary studies either for clade calibration, or as terminals in a dataset including morphological characters. The strength of these methodological advances relies however on the quality and completeness of the fossil record. For crickets (Insecta, Orthoptera, Gryllidea), few ancient (pre-Cenozoic) well-preserved fossils are known, except for isolated wings often classified in purely fossil groups and a few fossils found in Cretaceous amber. Here, we present two remarkable fossils from mid-Cretaceous amber of France, that were imaged using X-ray synchrotron microtomography and exhibit an exquisite preservation allowing description with a precision similar to that of extant taxa. Palaeonemobius occidentalis Laurent and Desutter-Grandcolas, gen. nov., sp. nov. and Picogryllus carentonensis Josse and Desutter-Grandcolas, gen. nov., sp. nov. are the oldest representatives of the Nemobiinae and Podoscirtinae subfamilies of the Trigonidiidae and Oecanthidae families respectively. P. carentonensis Josse and Desutter-Grandcolas, gen. nov., sp. nov. is also the smallest adult male with a full stridulatory apparatus ever documented in crickets (body length 3.3 mm), and the first taxon of the cricket clade for which male genitalia can be partly described. We discuss the significance of Cretaceous fossils of crickets for future evolutionary studies of this clade. [ABSTRACT FROM AUTHOR]

ABSTRACT Pair-formation, courtship, copulatory, and post-copulatory behaviors of Eidmanacris meridionalis Desutter-Grandcolas, 1995, were described under laboratory conditions and compared with congeneric species and other Phalangopsidae crickets whose mating behavior has been previously studied. Field observations for the species are also reported. Mating behaviors were observed in E. meridionalis couples: they first remained motionless, and then began walking through the arena screening the substrate. Mating behavior started with antennal contact, followed by males positioning themselves in front of females, that, when receptive, mounted on the males back and started feeding on metanotum secretions of the males. Copulation (female-above-male position) started with the engaging of copulatory structures and stopped with couple detachment. The end-to-end position was observed once, right after couple detachment. Males always remained with the spermatophore, which was eaten after removal or, alternatively, left in the substrate. The main differences in mating behavior of Eidmanacris species regard the mating position and the duration of the reproductive stages, suggesting that other reproductive repertoires can be observed in the genus since 27 species have not yet been studied in regards their reproductive behavior. We can also assume that the morphological, genetic, and chemical diversity found among the species of Phalangopsidae reflects in the behaviors of pair-formation, courtship, copulation, and post-copulation, leading to a diversity of copulation positions, duration of the stages, methods of attracting partners and parental investment. The description of Phalangopsidae mating patterns can provide important information for future evolutionary and phylogenetic studies, apart from useful for distinguishing cryptic species.

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grasshoppers (Orthoptera, suborders Ensifera and Caelifera) are often used as bioindicators to assess the effects of human‐induced land‐use changes. However, such assessment is largely depending on the methods that provide an accurate estimation. In the present study, we compared grasshopper species richness and assemblages on mountainous meadows in the Austrian Alps by applying a commonly used visual‐acoustic method and a novel soundscape method. For the visual‐acoustic method, we walked through the meadows for 1 h at a slow pace and recorded any visually and acoustically noticeable species. For the soundscape method, sound recorders combined with bat detectors were installed at fixed positions. Comparing both methods, there was no significant difference in species richness; however, we found significantly higher numbers of Caelifera species with the visual‐acoustic method and marginally higher numbers of Ensifera species with the soundscape method. Grasshopper assemblages differed marginally significantly between the two methods. With the soundscape method significantly more species were found between 12:00 and 17:00 hours compared to the samples taken between 10:00 and 12:00 hours. The soundscape method represents a reliable and by the observer unbiased technique to investigate grasshoppers within their environment. The visual‐acoustic method is especially preferable for the detection of non‐stridulating species which cannot be assessed with the soundscape method. Thus, researchers might consider using a sampling plan that mixes different sampling methods in order to offset potential limitations in sampling grasshopper species. [ABSTRACT FROM AUTHOR]

Barcode libraries are generally assembled with two main objectives in mind: specimen identification and species discovery/delimitation. In this study, the standard COI barcode region was sequenced from 681 specimens belonging to katydids (Tettigoniidae), cave crickets (Rhaphidophoridae), and leaf-rolling crickets (Gryllacrididae) from Zhejiang Province, China. Of these, four COI-5P sequences were excluded from subsequent analyses because they were likely NUMTs (nuclear mitochondrial pseudogenes). The final dataset consisted of 677 barcode sequences representing 90 putative species-level taxa. Automated cluster delineation using the Barcode of Life Data System (BOLD) revealed 118 BINs (Barcodes Index Numbers). Among these 90 species-level taxa, 68 corresponded with morphospecies, while the remaining 22 were identified based on reverse taxonomy using BIN assignment. Thirteen of these morphospecies were represented by a single barcode (so-called singletons), and each of 19 morphospecies were split into more than one BIN. The consensus delimitation scheme yielded 55 Molecular Operational Taxonomic Units (MOTUs). Only four morphospecies (Imax > DNN) failed to be recovered as monophyletic clades (i.e., Elimaea terminalis, Phyllomimus klapperichi, Sinochlora szechwanensis and Xizicus howardi), so it is speculated that these may be species complexes. Therefore, the diversity of katydids, cave crickets, and leafrolling crickets in Zhejiang Province is probably slightly higher than what current taxonomy would suggest. [ABSTRACT FROM AUTHOR]

Simple Summary: Feeding habits were the main factor affecting the gut microbial community structure of Ensifera (Insecta: Orthoptera). The gut microbial communities of Ensifera with different feeding habits were significantly different, as insects with more diverse feeding habits had gut microorganisms with less specific functions. However, feeding habits are not the only factors that affect the gut microbial community structure of Ensifera. Factors related to energy and nutrition acquisition also affect them, such as the abundance of some microbial functional genes unrelated to feeding habits but related to survival. Feeding habits were the primary factor affecting the gut bacterial communities in Ensifera. However, the interaction mechanism between the gut microbiota and feeding characteristics is not precisely understood. Here, the gut microbiota of Ensifera with diverse feeding habits was analyzed by shotgun metagenomic sequencing to further clarify the composition and function of the gut microbiota and its relationship with feeding characteristics. Our results indicate that under the influence of feeding habits, the gut microbial communities of Ensifera showed specific characteristics. Firstly, the gut microbial communities of the Ensifera with different feeding habits differed significantly, among which the gut microbial diversity of the herbivorous Mecopoda niponensis was the highest. Secondly, the functional genes related to feeding habits were in high abundance. Thirdly, the specific function of the gut microbial species in the omnivorous Gryllotalpa orientalis showed that the more diverse the feeding behavior of Ensifera, the worse the functional specificity related to the feeding characteristics of its gut microbiota. However, feeding habits were not the only factors affecting the gut microbiota of Ensifera. Some microorganisms' genes, whose functions were unrelated to feeding characteristics but were relevant to energy acquisition and nutrient absorption, were detected in high abundance. Our results were the first to report on the composition and function of the gut microbiota of Ensifera based on shotgun metagenomic sequencing and to explore the potential mechanism of the gut microbiota's association with diverse feeding habits. [ABSTRACT FROM AUTHOR]

Detection of sound and substrate vibration is crucial for the survival and reproduction of many animals, particularly insects. Bushcrickets (Orthoptera, Tettigoniidae), developed a large mechanosensory organ complex in their legs to detect such stimuli. As demonstrated by various studies in the past, sensilla in distinct functional groups form specialized vibratory organs (the subgenual organ and the accessory organ), respond sensitively to both vibration and sound (in the intermediate organ [IO]), or mediate hearing (in the crista acustica [CA]; the tympanal hearing organ). In their recent publication, Zhantiev and Korsunovskaya addressed auditory and vibratory sensitivity in the IO and the CA in two species of bushcrickets, using single‐cell recording and staining of sensory neurons from their soma in an isolated foreleg. Their main finding was that not only the IO but also the complete CA contains bimodal sensilla responding with high sensitivity to both sound and vibration, which would be a true change in the paradigm of how the auditory/vibratory sense in Orthoptera works. In addition, they revealed vibratory tuning of the IO sensilla, which differs largely from that in previous studies. We propose three major experimental causes of such discrepancies: calibration, experiments with isolated legs, and differences in the sites of recording. To judge the causes of these discrepancies more adequately, a detailed comparison of methods and a number of control experiments are needed. This will deepen our understanding of sensory adaptations and specialization of insect mechanosensory organs to stimuli entering the system by different input pathways. Highlights: A recent publication reports high sensitivity to both sound and vibration in a specialized hearing organ of bushcrickets, which was not found in other studies.We discuss vibratory stimulation as a potential cause for divergent results. [ABSTRACT FROM AUTHOR]

We describe the general occurrence in animal cells of elastic components ("tethers") that connect individual chromosomes moving to opposite poles during anaphase. Tethers, originally described in crane-fly spermatocytes, exert force on chromosome arms opposite to the direction the anaphase chromosomes move. We show that they exist in a broad range of animal cells. Thus tethers are previously unrecognised components of general mitotic mechanisms that exert force on chromosomes and they need to be accounted for in general models of mitosis in terms of forces on chromosomes and in terms of what their roles might be.

The forewing base structure of the orthopteran suborder Ensifera, a group of insects well known for their sound-producing behavior, was examined by using light microscopy, confocal laser scanning microscopy, and µCT. We detected significant novel characters, such as functional changes in the tpm9 muscle from the flexor to the extensor of the forewing that are likely associated with the acquisition of sound-producing behavior using forewings. Phylogenetic analysis based on the characters selected from the forewing base structure showed that the character system contains a strong phylogenetic signal supporting the monophyly of Ensifera, Tettigonioidea and Grylloidea as well as the sister-group relationship between Grylloidea and Gryllotalpoidea, but no apomorphies to resolve the deep phylogeny among superfamilies could be determined from this character system. [ABSTRACT FROM AUTHOR]

The orthopteran fauna of the Paleocene of Menat Formation (France) is revised. It comprises at least 12 species in the following clades: Grylloidea (an undescribed species, Menatgryllus longixiphus gen. et sp. nov.); Tettigoniidae (Prophasgonura lineatocollis); Elcanidae (Cenoelcanus menatensis gen. et sp. nov.); two Eumastacoidea (Paleochina duvergeri gen. et sp. nov. and Paleochina minuta sp. nov., tentatively placed in the extant family Chorotypidae). These two last taxa are compared to the other described fossil Eumastacoidea. As all these Eumastacoidea are represented by tegmina or hindwings, their previous attributions to the Eumastacidae sensu stricto are questionable. All previously described fossil Caelifera from Menat are considered of uncertain position. Those that were previously considered as Acridoidea are excluded from this clade. In consequence, the oldest described Acridoidea are Oligocene, at the time of diversification of the grasses on which these insects predominantly live, in accordance with the most recent molecular dating of the Acrididae. Cenoelcanus menatensis is the youngest and first Cenozoic representative of the Mesozoic Elcanidae, showing that this family survived the Cretaceous–Paleocene extinction and became extinct during the Paleogene.

Se presenta información específica de los ejemplares del infraorden Gryllidea depositados en la Colección Entomológica LOU-Arthr del Centro de Investigación Forestal de Lourizán y se revisa su estado de conocimiento en Galicia. Actualmente la colección cuenta con 450 ejemplares pertenecientes a cuatro de las cinco familias conocidas de la península ibérica (Gryllidae, Trigonidiidae, Mogoplistidae y Gryllotalpidae), seis subfamilias (Gryllinae, Oecanthinae, Trigonidiinae, Nemobiinae, Mogoplistinae y Gryllotalpinae), y 10 táxones [Eugryllodes escalerai (Bolívar, 1894), Gryllus (Gryllus) campestris Linnaeus, 1758, Gryllus (Gryllus) bimaculatus De Geer, 1773, Eumodicogryllus bordigalensis (Latreille, 1804), Oecanthus pellucens pellucens (Scopoli, 1763), Trigonidium (Trigonidium) cicindeloides Rambur, 1838, Nemobius sylvestris sylvestris (Bosc, 1792), Pteronemobius (Stilbonemobius) lineolatus (Brullé, 1835), Pseudomogoplistes vicentae Gorochov, 1996 y Gryllotalpa vineae Bennet-Clark, 1970]. Se citan por primera vez G. (G.) campestris para Lugo, O. pellucens pellucens para Lugo y Ourense, T. (T.) cicindeloides para A Coruña, Pt. (St.) lineolatus para Lugo, Ourense y Pontevedra, E. bordigalensis para Ourense y Pontevedra y G. vineae para Galicia.

During field surveys conducted in 2019, supplemented by Malaise trap captures dating back to 1998, we documented 50 species of Orthoptera from eight sites in the George Washington Memorial Parkway in northeastern Virginia. Anaxipha vernalis Walker and Funk and A. tinnulacita Walker and Funk were collected for the first time from Virginia. Neoconocephalus nebrascensis (Bruner) and N. lyristes (Rehn and Hebard) were documented for the first time from the same East Coast site in Great Falls Park. A slight range extension was documented for Gryllus pennsylvanicus Burmeister and N. nebrascensis. The most commonly collected species were Anaxipha exigua (Say), Tettigidea armata Morse, Hapithus (Orocharis) saltator (Uhler), H. agitator Uhler, and Amblycorypha oblongifolia (De Geer). Sweep netting was the most productive capture method. One non-native (adventive) species, Velarifictorus micado (Saussure), was documented from the study area. Two arboreal katydids, Pterophylla camellifolia (Fabricius) and Microcentrum rhombifolium (Saussure), were heard, but not collected. Our results provide baseline information on the species of Orthoptera occurring in this heavily trafficked national park. [ABSTRACT FROM AUTHOR]

Feeding habits were the primary factor affecting the gut bacterial communities in Ensifera. However, the interaction mechanism between the gut microbiota and feeding characteristics is not precisely understood. Here, the gut microbiota of Ensifera with diverse feeding habits was analyzed by shotgun metagenomic sequencing to further clarify the composition and function of the gut microbiota and its relationship with feeding characteristics. Our results indicate that under the influence of feeding habits, the gut microbial communities of Ensifera showed specific characteristics. Firstly, the gut microbial communities of the Ensifera with different feeding habits differed significantly, among which the gut microbial diversity of the herbivorous Mecopoda niponensis was the highest. Secondly, the functional genes related to feeding habits were in high abundance. Thirdly, the specific function of the gut microbial species in the omnivorous Gryllotalpa orientalis showed that the more diverse the feeding behavior of Ensifera, the worse the functional specificity related to the feeding characteristics of its gut microbiota. However, feeding habits were not the only factors affecting the gut microbiota of Ensifera. Some microorganisms’ genes, whose functions were unrelated to feeding characteristics but were relevant to energy acquisition and nutrient absorption, were detected in high abundance. Our results were the first to report on the composition and function of the gut microbiota of Ensifera based on shotgun metagenomic sequencing and to explore the potential mechanism of the gut microbiota’s association with diverse feeding habits.

Genomic size variation has long been a focus for biologists. However, due to the lack of genome size data, the mechanisms behind this variation and the biological significance of insect genome size are rarely studied systematically. The detailed taxonomy and phylogeny of the Ensifera, as well as the extensive documentation concerning their morphological, ecological, behavioral, and distributional characteristics, make them a strong model for studying the important scientific problem of genome size variation. However, data on the genome size of Ensifera are rather sparse. In our study, we used flow cytometry to determine the genome size of 32 species of Ensifera, the smallest one being only 1C = 0.952 pg with the largest species up to 1C = 19.135 pg, representing a 20-fold range. This provides a broader blueprint for the genome size variation of Orthoptera than was previously available. We also completed the assembly of nine mitochondrial genomes and combined mitochondrial genome data from public databases to construct phylogenetic trees containing 32 species of Ensifera and three outgroups. Based on these inferred phylogenetic trees, we detected the phylogenetic signal of genome size variation in Ensifera and found that it was strong in both males and females. Phylogenetic comparative analyses revealed that there were no correlations between genome size and body size or flight ability in Tettigoniidae. Reconstruction of ancestral genome size revealed that the genome size of Ensifera evolved in a complex pattern, in which the genome size of the grylloid clade tended to decrease while that of the non-grylloid clade expanded significantly albeit with fluctuations. However, the evolutionary mechanisms underlying variation of genome size in Ensifera are still unknown.

Male crickets and their close relatives bush-crickets (Gryllidae and Tettigoniidae, respectively; Orthoptera and Ensifera) attract distant females by producing loud calling songs. In both families, sound is produced by stridulation, the rubbing together of their forewings, whereby the plectrum of one wing is rapidly passed over a serrated file on the opposite wing. The resulting oscillations are amplified by resonating wing regions. A striking difference between Gryllids and Tettigoniids lies in wing morphology and composition of song frequency: Crickets produce mostly low-frequency (2–8 kHz), pure tone signals with highly bilaterally symmetric wings, while bush-crickets use asymmetric wings for high-frequency (10–150 kHz) calls. The evolutionary reasons for this acoustic divergence are unknown. Here, we study the wings of actively stridulating male field-crickets (Gryllus bimaculatus) and present vibro-acoustic data suggesting a biophysical restriction to low-frequency song. Using laser Doppler vibrometry (LDV) and brain-injections of the neuroactivator eserine to elicit singing, we recorded the topography of wing vibrations during active sound production. In freely vibrating wings, each wing region resonated differently. When wings coupled during stridulation, these differences vanished and all wing regions resonated at an identical frequency, that of the narrow-band song (∼5 kHz). However, imperfections in wing-coupling caused phase shifts between both resonators, introducing destructive interference with increasing phase differences. The effect of destructive interference (amplitude reduction) was observed to be minimal at the typical low frequency calls of crickets, and by maintaining the vibration phase difference below 80°. We show that, with the imperfect coupling observed, cricket song production with two symmetric resonators becomes acoustically inefficient above ∼8 kHz. This evidence reveals a bio-mechanical constraint on the production of high-frequency song whilst using two coupled resonators and provides an explanation as to why crickets, unlike bush-crickets, have not evolved to exploit ultrasonic calling songs.

Genomic size variation has long been a focus for biologists. However, due to the lack of genome size data, the mechanisms behind this variation and the biological significance of insect genome size are rarely studied systematically. The detailed taxonomy and phylogeny of the Ensifera, as well as the extensive documentation concerning their morphological, ecological, behavioral, and distributional characteristics, make them a strong model for studying the important scientific problem of genome size variation. However, data on the genome size of Ensifera are rather sparse. In our study, we used flow cytometry to determine the genome size of 32 species of Ensifera, the smallest one being only 1C = 0.952 pg with the largest species up to 1C = 19.135 pg, representing a 20-fold range. This provides a broader blueprint for the genome size variation of Orthoptera than was previously available. We also completed the assembly of nine mitochondrial genomes and combined mitochondrial genome data from public databases to construct phylogenetic trees containing 32 species of Ensifera and three outgroups. Based on these inferred phylogenetic trees, we detected the phylogenetic signal of genome size variation in Ensifera and found that it was strong in both males and females. Phylogenetic comparative analyses revealed that there were no correlations between genome size and body size or flight ability in Tettigoniidae. Reconstruction of ancestral genome size revealed that the genome size of Ensifera evolved in a complex pattern, in which the genome size of the grylloid clade tended to decrease while that of the non-grylloid clade expanded significantly albeit with fluctuations. However, the evolutionary mechanisms underlying variation of genome size in Ensifera are still unknown. [ABSTRACT FROM AUTHOR]

The widespread Mediterranean cricket, Arachnocephalus vestitus (Orthoptera: Mogoplistidae), is hereby reported as a new record for Georgia. In total, four females have been examined in 2020 and 2021, of which three specimens have been collected, and the information on the fourth one is based on photographic evidence. Cytochrom oxydase I (COI) barcoding further validates our finding. [ABSTRACT FROM AUTHOR]

Steppes and xerothermic grasslands are hotspots of biodiversity, but are threatened by habitat destruction and fragmentation. The heath bush-cricket, Gampsocleis glabra, is considered to be a specialist of xerothermic habitats and appears in national red lists as a threatened species in several European countries. The goal of the current research was to determine the habitat requirements of G. glabra in an isolated habitat patch in Poland, at the northern edge of its range. By comparing the composition of plant species and vegetation architecture of vacant and occupied sites in the summers of 2018 and 2019, it was found that this population of G. glabra still maintained a strict specialisation for the xerothermofilous Festuco-Brometea plant community. On the contrary to previous studies, however, Stipa-type grasses were not essential for the occurrence of the species and the majority of occupied areas were based on the plant Brachypodium pinnatum. The physiognomy of plant communities was crucial for the abundance of stridulating males, which showed a preference for dense grasses at 10 cm high. The habitat characteristics of patches occupied by males and females did not differ significantly. The study of habitat requirements of this endangered Orthoptera species in an isolated habitat patch could serve as a prelude to the restoration of similar locations before it becomes extinct. This study may also underpin the development of a global conservation strategy for G. glabra. [ABSTRACT FROM AUTHOR]

The orthopteran fauna of the Paleocene of Menat Formation (France) is revised. It comprises at least 12 species in the following clades: Grylloidea (an undescribed species, Menatgryllus longixiphus gen. et sp. nov.); Tettigoniidae (Prophasgonura lineatocollis); Elcanidae (Cenoelcanus menatensis gen. et sp. nov.); two Eumastacoidea (Paleochina duvergeri gen. et sp. nov. and Paleochina minuta sp. nov., tentatively placed in the extant family Chorotypidae). These two last taxa are compared to the other described fossil Eumastacoidea. As all these Eumastacoidea are represented by tegmina or hindwings, their previous attributions to the Eumastacidae sensu stricto are questionable. All previously described fossil Caelifera from Menat are considered of uncertain position. Those that were previously considered as Acridoidea are excluded from this clade. In consequence, the oldest described Acridoidea are Oligocene, at the time of diversification of the grasses on which these insects predominantly live, in accordance with the most recent molecular dating of the Acrididae. Cenoelcanus menatensis is the youngest and first Cenozoic representative of the Mesozoic Elcanidae, showing that this family survived the Cretaceous--Paleocene extinction and became extinct during the Paleogene. [ABSTRACT FROM AUTHOR]

The Crato Formation (Santana Group, Araripe Basin, Brazil) bears a high abundance of fossils in exceptional state of preservation, with insects from the order Orthoptera standing out. However, so far, few studies have explored their preserved inner organs in detail. Here, we provide the first detailed description of fossilized proventriculi from nine Grylloidea (Orthoptera: Ensifera) specimens of the Crato Formation. In all analyzed specimens, the external cuticle of the abdomen is cracked exposing the proventriculi, which are preserved as a tridimensional organ with a globular body and a tubular neck, similar to that of modern crickets. However, in the globular region of all fossils analyzed there are 9–12 rows of parallel divisions, differing from the modern crickets which have, more frequently, six. SEM images of two specimens revealed the exceptional preservation of internal median teeth, folds, and microvilli texture preserved in the organ. • Grylloidea from Crato were recovered with their tridimensional proventriculi preserved. • The fossilized proventriculi are similar to that of modern crickets. • SEM micrographs revealed exquisite preservation of structures in the organs. [ABSTRACT FROM AUTHOR]

Data on finds new for Belarus of the steppe species of crickets Oecanthus pellucens (Scopoli, 1763) and Modicogryllus frontalis (Fieber, 1844) are given. The material was collected in August 2019 and May and July 2020 in Bragin district of Gomel oblast. Brief information on the current distribution, as well as the characteristics of biology and ecology of each species, is presented. [ABSTRACT FROM AUTHOR]

Insect antennae carry diverse sensory organs for detecting information about their environments and facilitating interaction among individuals, particularly for reproductive behaviour. As such they are predicted to be sexually dimorphic, especially in species which do not use visual or auditory mate-location. The cave wētā are such animals, suggesting that they rely heavily on chemical and tactile information to interact. Sensilla morphology and sexual dimorphism was investigated in two species; Pachyrhamma acanthocera and P. waitomoensis, using scanning electron microscopy. Fourteen types of sensilla basiconica, campaniformia, chaetica, coeloconica, trichodea and Böhm's sensilla were identified. Among these, sexual dimorphism in the length of four subtypes was detected, and surprisingly, P. waitomoensis males completely lacked all but two of the porous sensilla types. In addition, three types of unique horn-like and hooked antennal protrusions in male P. acanthocera are described, along with similar, but less diverse structures on the antennae of male P. waitomoensis. [ABSTRACT FROM AUTHOR]

Flightless Transylvanian Dark Bush-cricket Pholidoptera transsylvanica is subendemic to the Carpathians and the Pannonian basin and one of ten species of European Community interest. In the last few years we have increased survey efforts aimed to obtain distributional data for this species along the northern range margin in Western Carpathian mountains covering most of Slovakia and reaching also south of Poland. Thus in Slovakia, where only 5 sites were known in 1996, 56 sites are known in 2017. The species was discovered for the first time in Poland in July 2017, in two sites in the south-eastern part of the country. Both sites are located in submountain mesophilous meadows of the alliance Arrhenatherion elatioris Luquet 1926, in its various successional stages along mainly mixed forests dominated with European beech and in alluvial vegetation. The presence of the species in these new sites is at the northern edge of its distribution area, and we suppose that only lack of data and no surveys in the past caused this knowledge gap. Data on its habitat and main threats and conservation measures of the species are discussed, and accompanying orthopteran species are characterised. [ABSTRACT FROM AUTHOR]

Ensifera is an extremely diverse group in the order Orthoptera, and it has been the subject of considerable research, especially in terms of phylogeny and bioacoustics. Katydids are known for using high-frequency broadband signals whereas most cricket songs are pure tones with a frequency range of 2–8 kHz. Pseudophyllus titan is a special katydid emits low-frequency pure tone songs similar to that of crickets. Acoustic communication of Ensifera were widely studied, but song evolution could deserve new examination taking into account the newly available phylogenies. To examine the song evolution of P. titan in the Ensifera, the mitogenomes of P. titan and three other ensiferan species (Sphagniana ussuriana, Oecanthus sinensis, Truljalia hibinonis) were obtained by high-throughput sequencing. In addition, the phylogeny of Ensifera was reconstructed including 63 in-group taxa, and the divergence time was further estimated for major ensiferan lineages. Lastly, the evolutions of song frequency were evaluated based on an ancestral character state reconstruction (ACSR). Moreover, we have studied the calling songs of 78 katydids and performed ACSR based on five genes. All phylogeny analyses confirmed that the superfamily Schizodactyloidea was placed basally to the non-grylloid clade. P. titan was in the Pseudophyllinae clade, and this clade had a distant relationship form other lineages in Phaneropteridae. The ACSR showed that P. titan evolved low-frequency pure tone songs independently after ancestors of katydids evolved high-frequency broadband noise. Referring to the geologic time scale, we suggest that the song frequency evolution in the Ensifera to some extent caused by adaptations to the changing habitat under conditions of climate change and plant evolution. [ABSTRACT FROM AUTHOR]

The Tisza River Basin is an important area as it is a green corridor in which there are highly endangered habitats and a high level of biodiversity. The patterns in the species richness of invertebrates and the environmental conditions affecting these patterns are poorly studied in the grassy habitats in the lower reaches of the Tisza River Basin. The present study focuses on the effects of flooding, habitat and landscape features on the species richness of orthopterans at 24 grassland sites in two different landscapes. The relations between the explanatory variables and the pattern of diversity of orthopterans with different life-history traits were studied, using ordination and Generalized Linear Mixed Models. Although the influential factors for the different trait groups differed, we suggest that landscape features are the most important in shaping orthopteran assemblages, whereas habitat characteristics and flooding have comparatively little effect. Habitat characteristics affected only the non-xerophilous and Ensifera species and only the species richness of non-xerophilous orthopterans in flooded and non-flooded sites differed. We emphasize that even in countries where there are still considerable areas of high value natural grasslands, such as Hungary, non-protected meadows, linear grassy habitats (dikes, ditch banks, road verges, etc.) need more attention and should be given higher priority in the conservation of invertebrates.