Mantodea (praying mantises) is a group of exclusively predatory insects, which, together with nonraptorial blattodeans (cockroaches and termites) and groups exclusively found in the fossil record, form the group Dictyoptera. A central characteristic of Mantodea is the specialization of their first pair of legs as raptorial grasping appendages, but the evolution from walking to raptorial legs is not yet fully understood. Here, we trace the evolution of the raptorial appendages in Dictyoptera through time using a morphometric (morphospaces) approach. We also describe two new mantodean nymphs preserved in amber from the Cretaceous and Eocene, which expand the scarce mantodean fossil record. Blattodean and mantodean appendages appear distinct in morphospace, but several appendages of fossil non-mantodeans can be considered raptorial, providing a potential transitional link between walking and raptorial morphotypes. Therefore, we discuss potential mantodean affinities for other predatory fossil dictyopterans. We examine changes across extant mantodeans, characterized by a straightening of the tibia especially associated with the rise of the diversification of the Mantidea and discuss whether a thickening of the femur could reflect an early adaptation to cursorial hunting.

A taxonomic study of Korean Mantodea using morphological and molecular characters (COI) is presented. Eight species [Amantisnawai (Shiraki, 1908), Acromantisjaponica Westwood, 1889, Mantisreligiosasinica Bazyluk, 1960, Statiliamaculata (Thunberg, 1784), Tenoderaangustipennis Saussure, 1869, T.sinensis Saussure, 1871, Hierodulachinensis Werner, 1929, H.patellifera (Audinet-Serville, 1838)] belonging to six genera in three families are recognized. Interspecific genetic divergence of COI using uncorrected p-distance ranged from 6.7% to 22.4%, while intraspecific divergence ranged from 0% to 2.2% among eight Korean Mantodea species. All eight species were each strongly supported as a single lineage using COI on both neighbor-joining and parsimony trees. An illustrated key, redescriptions, habitus photographs, and illustrations of diagnostic characters of the species of Korean Mantodea are provided to facilitate identification.

Exaggerated sexual traits, such as ornaments and courtship displays, are crucial for mate acquisition in many species and are often subject to directional runaway selection. However, in the face of high predation risk, natural selection can result in a reduction of conspicuous precopulatory displays to avoid detection by potential predators. Sexual selection may then favour increased investment in inconspicuous postcopulatory traits. Here, we investigated the transgenerational effects of predation on precopulatory male courtship and postcopulatory sexual traits (testes size, sperm length) in a dung fly, Sepsis punctum (Sepsidae). Behavioural assays prior to selection document a marked decrease in male courtship displays in the presence of a predator, the Asian Ant Mantis (Odontomantis planiceps). However, after ten generations of experimental evolution, flies exhibited a marked increase in courtship, both in the absence and presence of a predator. Additionally, under sustained predation pressure, male and female body size decreased but male postcopulatory traits were not significantly affected. These results suggest that precopulatory courtship can be under strong sexual selection even in the face of predation pressure. Larger flies were more susceptible to predation, and there could be canalisation of postcopulatory traits that are crucial for fertilisation.

Predators are not perfect, as some of their prey capture attempts result in failure. Successful attempts may be partly due to predators modulating their capture kinematics in relation to variation in the visual cues of the prey to increase the probability of success. In praying mantises, which have been suggested to possess stereoscopic vision, variation in prey distance has been shown to elicit variation in the probability of an attempt. However, it remains to be examined whether variation in prey distance results in mantises modulating their attempt to successfully capture prey. The goals of this study were to examine these relationships using the praying mantis system. Using 11 adult female Sphodromantis lineola, we recorded 192 prey capture attempts at 1000 Hz with two cameras to examine the 3D kinematics of successful and unsuccessful prey capture attempts. Using a combination of principal component analysis (PCA) and logistic regression, our results show that as prey distance increases, mantises adjust through greater and faster expansion of the forelegs and body (PC1), which significantly predicts capture success. However, PC1 only explains 22% of the variation in all prey capture attempts, suggesting that the other components may be related to additional aspects of the prey. Our results suggest that the distances at which mantises prefer to attempt to capture prey may be the result of their greater probability of successfully capturing the prey. These results highlight the range of motions mantises use when attempting to capture prey, suggesting flexibility in their prey capture attempts in relation to prey position.

Praying mantises are the apex insect predators in many ecosystems, nevertheless they receive relatively less recognition in biodiversity reviews. We report a first survey of diversity of praying mantises in Cameroon, which is situated in the Congo Basin region, one of the richest biodiversity hotspots. Combination of light trapping with manual collecting resulted in 495 specimens representing 62 species. A total of eight species are novel for the country, at least five species are likely undescribed. DNA barcodes of 72 specimens representing every collected species were obtained, curated, and submitted to NCBI database. For eight species, barcodes are published for the first time. A maximum likelihood phylogenetic tree was created using all available barcodes of Mantodea of Central African subregion. The results obtained during this study stress the importance of combining traditional and molecular approaches during biodiversity assessments of often neglected taxa, the latter aiding in uncovering new species, resolving unknown morphological divergencies and assigning conspecifics.

The praying mantis Creobroter nebulosa Zheng (Mantedea: Hymenopodidae) is an insect that has medicinal and esthetical importance, and being a natural enemy for many insects, the species is used as a biological control agent. In this publication, we used scanning electron microscopy (SEM) to study the fine morphology of antennae of males and females of this species. The antennae of both sexes are filiform and consist of three parts: scape, pedicel, and flagellum (differing in the number of segments). Based on the external morphology and the sensilla distribution, the antennal flagellum is could be divided into five regions. Seven sensilla types and eleven subtypes of sensilla were observed: grooved peg sensillum (Sgp), Bohm bristles (Bb), basiconic sensillum (Sb), trichoid sensillum (StI, StII), campaniform sensillum (Sca), chaetic sensillum (ScI, ScII, ScIII), and coeloconic sensillum (ScoI, ScoII). In Mantodea, the ScoII is observed for the first time, and it is located on the tip of the flagellum. The external structure and distribution of these sensilla are compared to those of other insects and possible functions of the antennal sensilla are discussed. The males and females of the mantis could be distinguished by the length of antennae and number of Sgp. Males have antennae about 1.5 times longer and have significantly larger number of Sgp compared to females. The sexual difference in distribution of the Sgp suggests that this type of sensilla may play a role in sex-pheromones detection in mantis.

Arthropods\' eyes are effective biological vision systems for object tracking and wide field of view because of their structural uniqueness; however, unlike mammalian eyes, they can hardly acquire the depth information of a static object because of their monocular cues. Therefore, most arthropods rely on motion parallax to track the object in three-dimensional (3D) space. Uniquely, the praying mantis (Mantodea) uses both compound structured eyes and a form of stereopsis and is capable of achieving object recognition in 3D space. Here, by mimicking the vision system of the praying mantis using stereoscopically coupled artificial compound eyes, we demonstrated spatiotemporal object sensing and tracking in 3D space with a wide field of view. Furthermore, to achieve a fast response with minimal latency, data storage/transportation, and power consumption, we processed the visual information at the edge of the system using a synaptic device and a federated split learning algorithm. The designed and fabricated stereoscopic artificial compound eye provides energy-efficient and accurate spatiotemporal object sensing and optical flow tracking. It exhibits a root mean square error of 0.3 centimeter, consuming only approximately 4 millijoules for sensing and tracking. These results are more than 400 times lower than conventional complementary metal-oxide semiconductor-based imaging systems. Our biomimetic imager shows the potential of integrating nature\'s unique design using hardware and software codesigned technology toward capabilities of edge computing and sensing.

Many insects rely heavily on visual cues in foraging and other life activities. Mantids are insect predators that usually ambush prey. The sophisticated visual system of mantids allows them to spot, track, and strike at prey with high accuracy. Mantids are categorized as diurnal animals in most cases, while our field observations suggested that they were active in foraging both day and night. Therefore, we hypothesize that predation in dim light is possible for mantids, while mantids are unable to capture prey in complete darkness. In this study, we experimentally examined whether different light conditions could affect the predation success and efficiency of mantid nymphs and adults, Hierodula chinensis Werner (Mantodea: Mantidae), through behavioral observations. Individual mantids were placed in individual chambers in complete darkness, simulated moonlight (0.1 lux), or simulated dusk (50 lux) conditions and were allowed to forage for prey items for 10 min. Our observations showed no evidence that H. chinensis could capture any prey in complete deprivation of light. The proportion of nymphs with successful predation in simulated moonlight was 50% higher than that in complete darkness and 45.83% lower than that in simulated dusk. The proportion of adults with successful predation in simulated moonlight was 42.11% higher than that in complete darkness and 57.89% lower than that in simulated dusk. Overall, the results provide new insights into the behavioral ecology of diurnal predators at night, with potential association with moonlight, starlight, and light pollution.

Praying mantids (Mantodea: Mantidae) are iconic insects that have captivated biologists for decades, especially the species with cannibalistic copulatory behavior. This behavior has been cited as evidence that insects lack nociceptive capacities and cannot feel pain; however, this behaviorally driven hypothesis has never been rigorously tested at the genetic or functional level. To enable future studies of nociceptive capabilities in mantids, we sequenced and assembled a draft genome of the Chinese praying mantis (Tenodera sinensis) and identified multiple classes of nociceptive ion channels by comparison to orthologous gene families in Arthropoda. Our assembly-produced using PacBio HiFi reads-is fragmented (total size = 3.03 Gb; N50 = 1.8 Mb; 4,966 contigs), but is highly complete with respect to gene content (BUSCO complete = 98.7% [odb10_insecta]). The size of our assembly is substantially larger than that of most other insects, but is consistent with the size of other mantid genomes. We found that most families of nociceptive ion channels are present in the T. sinensis genome; that they are most closely related to those found in the damp-wood termite (Zootermopsis nevadensis); and that some families have expanded in T. sinensis while others have contracted relative to nearby lineages. Our findings suggest that mantids are likely to possess nociceptive capabilities and provide a foundation for future experimentation regarding ion channel functions and their consequences for insect behavior.

Many predatory animals, such as the praying mantis, use vision for prey detection and capture. Mantises are known in particular for their capability to estimate distances to prey by stereoscopic vision. While the initial visual processing centers have been extensively documented, we lack knowledge on the architecture of central brain regions, pivotal for sensory motor transformation and higher brain functions. To close this gap, we provide a three-dimensional (3D) reconstruction of the central brain of the Asian mantis, Hierodula membranacea. The atlas facilitates in-depth analysis of neuron ramification regions and aides in elucidating potential neuronal pathways. We integrated seven 3D-reconstructed visual interneurons into the atlas. In total, 42 distinct neuropils of the cerebrum were reconstructed based on synapsin-immunolabeled whole-mount brains. Backfills from the antenna and maxillary palps, as well as immunolabeling of γ-aminobutyric acid (GABA) and tyrosine hydroxylase (TH), further substantiate the identification and boundaries of brain areas. The composition and internal organization of the neuropils were compared to the anatomical organization of the brain of the fruit fly (Drosophila melanogaster) and the two available brain atlases of Polyneoptera-the desert locust (Schistocerca gregaria) and the Madeira cockroach (Rhyparobia maderae). This study paves the way for detailed analyses of neuronal circuitry and promotes cross-species brain comparisons. We discuss differences in brain organization between holometabolous and polyneopteran insects. Identification of ramification sites of the visual neurons integrated into the atlas supports previous claims about homologous structures in the optic lobes of flies and mantises.