Raptorial Forelegs Research Articles

The first fossil mantis lacewing (Neuroptera: Mantispidae) from Australia

Mantispidae is a cosmopolitan family of neuropteran insects, with approximately 395 extant species (Ohl et al., 2004; Jepson, 2015; Engel et al., 2018; Li et al., 2023). The family includes some of the most distinctive of lacewings owing to their convergent traits with mantises (Mantodea), complete with elongate prothoraces, prominent and large compound eyes on a moveable head, and powerful raptorial forelegs. Indeed, species of the family are referred to as mantis lacewings or mantid lacewings owing to the considerable similarity. As one would suspect, adults are predatory on a variety of small-bodied arthropods, typically hunting during dusk or night (Snyman et al., 2020). Larvae are also predators, although some are specialised for particular prey (e.g., subfamily Symphrasinae), while those of the nominate subfamily Mantispinae are ectoparasitic on spider egg cases (Redborg, 1998). Extant Mantispidae are found on every continent except Antarctica but show their highest diversity and geographical distribution in Australia and the Americas (Fig. 1A).

New genera and species of Mantispoidea (Insecta, Neuroptera) from the mid-Cretaceous Kachin amber, Myanmar

Mantispoidea (Insecta, Neuroptera) are well-known for the hypermetamorphic larval development and for most adults having praying mantis-like raptorial forelegs. Currently, this superfamily comprises Berothidae (beaded lacewings) and three raptorial mantispoid families: Rhachiberothidae (thorny lacewings), Dipteromantispidae and Mantispidae (mantidflies or mantid lacewings). It includes about 530 extant species in 74 genera, and 143 extinct species in 97 genera from the Upper Triassic to the Miocene. Berothidae, well-known for some adults with scale-like setae on the female wings, currently includes 119 extant species in 26 genera, and 59 extinct species in 37 genera from the Upper Triassic to the Eocene. Rhachiberothidae represents the relictual group of Mantispoidea, comprising only 14 extant species across four genera, which are confined to the Afrotropical Region. However, the abundant fossil records (28 species and 21 genera), especially from the Cretaceous, highlight the past glory of this family. The Cretaceous dipteran-like family Dipteromantispidae, comprising ten species across nine genera, remains enigmatic in terms of its phylogenetic status. Mantispidae, the largest family within Mantispoidea, comprises approximately 395 extant species across 44 genera and 46 extinct species in 30 genera, ranging from the Lower Jurassic to the Miocene. This family is distinctive from other raptorial families for its highly mobile and variously elongated prothorax. Here, we describe several new genera and species from mid-Cretaceous Kachin amber, Myanmar: Three new species of Osmyloberotha Khramov, 2021 (O. dispersa sp. nov., O. chenzuyini Zhuo, Li & Liu sp. nov. and O. magnimaculata sp. nov.) in Berothidae, with a detailed redescription of O. simpla Khramov, 2021; two new genera and three new species (Paraberothinae: Paraberothoides longispina Li, Zhang & Liu gen. et sp. nov.; Subfamily unknown: Dicranoberotha zhangzhiqiae Zhuo, Li & Liu gen. et sp. nov., Dicranoberotha liumohanae Zhuo, Li & Liu gen. et sp. nov.) of Rhachiberothidae, three new species (Enigmadipteromantispa dilatata Li, Nakamine, Yamamoto & Liu sp. nov., Kurtodipteromantispa relicta Li, Nakamine, Yamamoto & Liu sp. nov. and Kurtodipteromantispa univenula sp. nov.) of Dipteromantispidae, as well as four new genera and five new species (Symphrasinae: Parvosymphrasites aploneura Li, Lin, Liu & Wang gen. et sp. nov. and Proplega evelynae Zhuo, Li & Liu gen. et sp. nov.; Subfamily unknown: Haplacantha robusta gen. et sp. nov., Haplacantha tenuis gen. et sp. nov. and Mesomantispoides felixoporcus gen. et sp. nov.) of Mantispidae. Sinuijumantispa So & Won, 2022, previously classified within Drepanicinae, is now recognized as a stem group of Mantispidae, which is possibly related to Mesomantispoides gen. nov. or Mesomantispinae. Our new findings offer crucial insights into the taxonomy, morphological diversity and evolution of Mantispoidea.

The associated evolution of raptorial foreleg and mantispid diversification during 200 million years.

Mantispidae have developed multidimensional specializations of predation that are leveraged by trade-offs involving attack properties, which is revealed by interdisciplinary analyses of phylogeny, morphometrics, and mechanical modeling. The lineage diversification was stimulated by its raptorial foreleg evolution, and was influenced by the ecosystem of corresponding periods, involving biotic and physical factors.

Extrinsic and intrinsic musculature of the raptorial forelegs in Mantodea (Insecta) in the light of functionality and sexual dimorphism.

Prehensile raptorial forelegs are prey capturing and grasping devices, best known for praying mantises (Mantodea) within insects. They show strong morphological and behavioral adaptations towarda lifestyle as generalist arthropod predators. In the past, few species of Mantodea were investigated, concerning morphological variability of the raptorial forelegs. Especially the knowledge of foreleg anatomy in the light of functional and comparative morphology is scarce. Our comparative approach is based on the, for arthropods very common, "female-biased sexual size dimorphism"(SSD) that occurs in almost every Mantodea species. Within Mantodea, this SSD is likely leading to a shift of the exploited ecological niche between male and female individuals due to changes in, for example, the possible prey size; which might be reflected in the chosen ecomorphs. In this context, we analyzed the musculature of the raptorial forelegs of female and male specimens in five different species with varying SSD, using high-resolution microcomputed tomography and dissection. We were able to confirm the presence of 15 extrinsic and 15 intrinsic muscles-including one previously undescribed muscle present in all species. Thus, presenting a detailed description and illustrative three-dimensional anatomical visualization of the musculature in Mantodea. Interestingly, almost no observable differences were found, neither between species, nor between the sexes. Furthermore, we homologized all described muscles, due to their attachment points, to the comprehensive nomenclature established by Friedrich and Beutel (2008), discussed potential functionality of the muscles and possible homologies to the neuropteran Mantispa styriaca (Büsse et al., 2021) and the newly introduced leg nomenclature by Aibekova et al. (2022). By elucidating the anatomy, particularly in the context of functionality and SSD, our results complement previous knowledge of the raptorial forelegs, and facilitate a better understanding of the underlying biomechanical system of the predatory strike, and ultimately, a future comparison to other insect taxa.

A new aquatic beetle (Adephaga: Coptoclavidae) from the Middle Jurassic Daohugou Biota.

Tigrivia baii gen. et sp. nov. (Coleoptera: Adephaga: Coptoclavidae) is described and named based on a fossil specimen from the Middle Jurassic Daohugou Biota, Nincheng County, Inner Mongolia of China. The fossil is very similar in morphology with the adult Coptoclava longipoda Ping 1928 (Laiyang Formation of Nanligezhuang Village, Laiyang City, Shandong Province, China, Lower Cretaceous, 121 ~ 120 Ma), but differs from C. longipoda by the adjacencies of two procoxae and two mesocoxae. T. baii gen. et sp. nov. differs from Daohugounectes primitinus Wang et al. 2010 by the absence of striae on the elytra and the absence of ventral eyes under the head. The new beetle species shows developed aquatic adaptions, such as specialized raptorial forelegs, and swimming middle and hind legs. Furthermore, it is speculated to lead a similar lifestyle as extant Dytiscoidae, according to the two eyes on the side of head and the absence of spiracles on ventrites. This new fossil expanded our knowledge of the diversity of the Middle Jurassic Coptoclavid beetles in Daohugou Biota and improved our understanding of their paleoecological significance.

New record of a mantis-like dictyopteran from the Lower Cretaceous Crato Formation (Brazil)

We present a new fossil representative of Dictyoptera (the group includes the modern Mantodea and Blattodea) from the Lower Cretaceous Crato Formation (Brazil). LP/UFC CRT 2221(a,b) is characterized by head orthognathous, antennae filiform, large eyes situated laterally, prothorax short, abdomen stout, raptorial forelegs folded and robust, at least prefemora with ventral row of spines and forewings tegminous protrude beyond the abdomen. The shape of the prothoracic appendage and its articulations indicate that the tibia opposes the femur as in most mantodeans. However, the shape and dimensions of the coxae and venation pattern in the apical part of the wing are commonly associated to blattodeans. Unfortunately, the preservation of the wing venation in the here described specimen is incomplete, which prevents a reliable and objective reconstruction of the exact venation pattern. Many species descriptions of fossil dictyopterans are mostly based on the wing venation, consequently, it is difficult to determine its taxonomic status. Although the incompleteness of the specimen does not allow for a formal description, the overall characteristics are consistent with primitive mantodean-type insects. Fossil representatives of transitional forms or side branch groups are rather scarce in the fossil record. Therefore, the specimen presented here may contribute to a better understanding of evolutionary events within Dictyoptera during the Cretaceous.

A new species of thorny lacewing (Neuroptera: Rhachiberothidae: Paraberothinae) from mid-Cretaceous Burmese amber with novel raptorial foreleg structure

A new species, namely Astioberotha coutreti sp. nov., of the thorny lacewing subfamily Paraberothinae, is described and illustrated from a complete individual preserved in mid-Cretaceous amber from Tanai, northern Myanmar. Astioberotha coutreti sp. nov. preserves nearly all the diagnostic characters of this subfamily, and differs from the type species of the genus Astioberotha owing to the fore femur with one long basal spine and 34 additional smaller spines; protibia bearing five distal spines; probasitarsus with two spines on inner edge located near mid-length; forewing with numerous maculation spots; intra-RP crossvein between RP3 and RP4 present (4rp3-rp4). Astioberotha coutreti sp. nov. together with the recent description of several other Paraberothinae species from the mid-Cretaceous Burmese amber, are used to discuss the palaeobiogeography of the subfamily.

Beetle bombing always deters praying mantises.

Some animals have evolved chemical weapons to deter predators. Bombardier beetles (Coleoptera: Carabidae: Brachininae: Brachinini) can eject toxic chemicals at temperatures of 100 °C from the tips of their abdomens, ‘bombing’ the attackers. Although some bombardier beetles can reportedly deter predators, few studies have tested whether bombing is essential for successful defence. Praying mantises (Mantodea) are ambush predators that attack various arthropods. However, it is unclear whether bombardier beetles deter mantises. To test the defensive function of bombing against praying mantises, I observed three mantis species, Tenodera sinensis, Tenodera angustipennis, and Hierodula patellifera (Mantidae), attacking the bombardier beetle Pheropsophus jessoensis (Carabidae: Brachininae: Brachinini) under laboratory conditions. All mantises easily caught the beetles using their raptorial forelegs, but released them immediately after being bombed. All of the counterattacked mantises were observed to groom the body parts sprayed with hot chemicals after releasing the beetles. When treated P. jessoensis that were unable to eject hot chemicals were provided, all mantises successfully caught and devoured the treated beetles. Therefore, bombing is essential for the successful defence of P. jessoensis against praying mantises. Consequently, P. jessoensis can always deter mantises.

Functional morphology of the raptorial forelegs in Mantispa styriaca (Insecta: Neuroptera)

The insect leg is a multifunctional device, varying tremendously in form and function within Insecta: from a common walking leg, to burrowing, swimming or jumping devices, up to spinning apparatuses or tools for prey capturing. Raptorial forelegs, as predatory striking and grasping devices, represent a prominent example for convergent evolution within insects showing strong morphological and behavioural adaptations for a lifestyle as an ambush predator. However, apart from praying mantises (Mantodea)—the most prominent example of this lifestyle—the knowledge on morphology, anatomy, and the functionality of insect raptorial forelegs, in general, is scarce. Here, we show a detailed morphological description of raptorial forelegs of Mantispa styriaca (Neuroptera), including musculature and the material composition in their cuticle; further, we will discuss the mechanism of the predatory strike. We could confirm all 15 muscles previously described for mantis lacewings, regarding extrinsic and intrinsic musculature, expanding it for one important new muscle—M24c. Combining the information from all of our results, we were able to identify a possible catapult mechanism (latch-mediated spring actuation system) as a driving force of the predatory strike, never proposed for mantis lacewings before. Our results lead to a better understanding of the biomechanical aspects of the predatory strike in Mantispidae. This study further represents a starting point for a comprehensive biomechanical investigation of the convergently evolved raptorial forelegs in insects.

Male coercion and female injury in a sexually cannibalistic mantis.

Sexual conflict can generate coercive traits in males that enhance mating success at the expense of female fitness. Pre-copulatory sexual cannibalism-where females consume males without mating-typically favours cautious rather than coercive mating tactics, and few examples of the latter are known. Here, we show that males of the highly cannibalistic springbok mantis, Miomantis caffra, wrestle females during pre-mating interactions. We find that most initial contacts between males and females involve a violent struggle whereby each sex tries be the first to grasp hold of the other with their raptorial forelegs. When females win the struggle, they always cannibalize males. However, when males grasp females first, they dramatically increase the chance of mating. We also find striking evidence that, on some occasions, males wound females with their fore-tibial claws during struggles, resulting in haemolymph loss and scar tissue formation. Taken together, our results show how males can overcome the threat of cannibalism by coercively wrestling females. We argue that pre-copulatory injury in this species is likely to be a negative pleiotropic side-effect of coercive mating behaviour and foraging morphology.

Cretaceous mantid lacewings with specialized raptorial forelegs illuminate modification of prey capture (Insecta: Neuroptera)

AbstractThe Mantispidae (Neuroptera), commonly known as mantid lacewings or mantispids, are characterized by raptorial forelegs used by adults for predation. They have a fossil history extending to the Early Jurassic. During the past 180 Myr, the lineage has undergone significant evolutionary transformation, exhibiting an elevated diversity in morphology yet retaining the same overall ground plan. Although raptorial foreleg morphology and capture behaviour are well documented in extant insects, they are poorly known for premodern lineages, attributable to the scarcity and poor preservation of fossils. Here, we report two new genera and species of Mantispidae from mid-Cretaceous Myanmar (Burmese) amber. Both taxa have highly specialized raptorial forelegs and highlight modification of capture strategy in Cretaceous Mantispidae. The foreleg of both species has one major spine that is the same length as the foretibia on the ventral surface of the forefemur, which faces the foretibia with a row of robust setae. The two new amber mantid lacewings provide structural and functional indications that represent an extinct mode of capture strategy. The new findings reveal the presence of a geochronologically rapid diversification of Mantispidae during the Early Cretaceous, thereby illuminating the varied morphologies involved in prey-capture strategies integral to the early evolution of mantispids.

Cretaceous diversity and disparity in a lacewing lineage of predators (Neuroptera: Mantispidae).

Mantidflies (Mantispidae) are an unusual and charismatic group of predatory lacewings (Neuroptera), whereby the adults represent a remarkable case of morphological and functional convergence with praying mantises (Mantodea). The evolutionary history of mantidflies remains largely unknown due to a scarcity of fossils. Here, we report the discovery of a highly diverse palaeofauna of mantidflies from the mid-Cretaceous (lowermost Cenomanian) of Myanmar. The raptorial forelegs of these mantidflies possess highly divergent morphological modifications, some of which are unknown among modern mantidflies, e.g. the presence of forked basal profemoral spines or even the complete loss of foreleg spine-like structures. A phylogenetic analysis of Mantispidae reveals a pattern of raptorial foreleg evolution across the family. The high species diversity and disparate foreleg characters might have been driven by diverse niches of predator-prey interplay in the complex tropical forest ecosystem of the mid-Cretaceous.

Hidden diversity of small predators: new thorny lacewings from mid-Cretaceous amber from northern Myanmar (Neuroptera: Rhachiberothidae: Paraberothinae)

AbstractThorny lacewings (Rhachiberothidae) are currently distributed only within Africa, whereas they are prevalent in the fossil record of various Cretaceous ambers across the Northern Hemisphere, with a handful of the fossil records from some Eocene European ambers. Four rhachiberothid species in four extinct genera are known from the mid-Cretaceous amber of northern Myanmar. Here, we report further examples of the remarkable palaeodiversity of this group from the same amber deposit, adding the four new fossil genera and seven new species:Acanthoberotha cuspisgen. et sp. nov.,Astioberotha falcipesgen. et sp. nov.,Stygioberotha siculiferagen. et sp. nov.,Uranoberotha chariessagen. et sp. nov.,Creagroparaberotha cuneatasp. nov.,Micromantispa galeatasp. nov. andM.spicatasp. nov. Based on a series of well-preserved specimens, we discuss the fine details of the raptorial forelegs and genital segments, which may be important for elucidating the phylogenetic relationships among genera. Our findings reveal an unexpectedly diverse assemblage of thorny lacewings in the Cretaceous System, highlighting the morphologically diverse rhachiberothids in Burmese amber. The discovery of seven additional rhachiberothid species in Myanmar amber suggests the potential for much higher diversity and abundance of the Cretaceous rhachiberothids than previously documented. Furthermore, morphological variation in the raptorial forelegs was found to be extremely diverse among the Burmese amber paraberothines, especially in terms of the size, number and shape of spines (or spine-like setae) on the inner edges of protibia, and the morphological structure of the probasitarsus.

A review of the biology and biogeography of Mantispidae (Neuroptera)

Abstract Adult Mantispidae are general predators of arthropods equipped with raptorial forelegs. The three larval instars display varying degrees of hypermetamorphic ontogeny. The larval stages exhibit a remarkable life history ranging from specialised predators of nest-building hymenopteran larvae and pupa, to specialised predators of spider-eggs, to possible generalist predators of immature insects. Noteworthy advances in our understanding of the biology of Mantispidae has come to light over the past two decades which are compiled and addressed in this review. All interactions of mantispids with other arthropods are tabled and their biology critically discussed and compared to the current classification of the taxon. Additionally, the ambigous systematics within Mantispidae and between Mantispidae and its sister groups, Rhachiberothidae and Berotidae, is reviewed. Considering the biology, systematics, distribution of higher taxonomic levels and the fossil record, the historical biogeography of the group is critically discussed with Gondwana as the epicenter of Mantispidae radiation.

Evolutionary diversification in the raptorial forelegs of Mantodea: Relations to body size and depth perception.

Limb proportions have evolved among animals to meet functional demands among diverse environments. Studies from terrestrial, vertebrate locomotion have demonstrated that variation in limb proportions have adaptively evolved so animals can perform in a given environment. Most of the research on limb proportion evolution is among vertebrates and terrestrial locomotion, with little information on limb segment evolution in invertebrates or for other functional roles. For example, among invertebrates, multisegmented raptorial forelimbs have evolved multiple times independently to capture prey, but there is little information on the adaptive evolution and diversity of these limbs. Furthermore, as feeding performance is influenced by the sensory system, few studies have examined the coevolution of sensory-motor systems. Using mantises (Mantodea) I examined forelimb diversification among 97 species with a combination of methods, including ternary plots for morphospace visualization, phylogenetically informed allometric relationships, and comparison of evolutionary rates of diversification. Furthermore, using head width as a proxy for depth perception, I examined the correlated evolution of foreleg diversity with depth perception. The results show that among the three segments of the foreleg, the tibia is the smallest, most diverse, and has the highest rate of evolution after body size corrections. Furthermore, while all foreleg segments were related to head width, head width explained the most variation in tibial length compared with other foreleg segments. The results suggest a potential adaptive functional role of tibia length related to the displacement or force produced in this mechanical lever. Furthermore, results from this study support distinct ecomorphs of mantises, as several independent evolutions to grass mimicry evolve similar morphologies. RESEARCH HIGHLIGHT: This study demonstrates interspecific variation among segments of an invertebrate raptorial foreleg. Among Mantodea species the tibia is the most diverse and is related to a proxy for depth perception, while the other segments had strong relationships with body size. This suggests an adaptive, functional role of the tibia during prey capture.

A mantidfly in Cretaceous Spanish amber provides insights into the evolution of integumentary specialisations on the raptorial foreleg

Multiple predatory insect lineages have developed a raptorial lifestyle by which they strike and hold prey using modified forelegs armed with spine-like structures and other integumentary specialisations. However, how structures enabling the raptorial function evolved in insects remains largely hypothetical or inferred through phylogeny due to the rarity of meaningful fossils. This is particularly true for mantidflies (Neuroptera: Mantispidae), which have a scarce fossil record mostly based on rock compressions, namely isolated wings. Here, Aragomantispa lacerata gen. et sp. nov. is described from ca. 105-million-year-old San Just amber (Spain), representing the oldest and one of the few mantidflies hitherto described from amber. The fossil shows exquisitely preserved forefemoral spine-like structures composed of integumentary processes each bearing a modified seta, and prostrate setae on foretibiae and foretarsi. The fine morphology of these structures was unknown in fossil mantidflies. An assessment of integumentary specialisations from raptorial forelegs across mantispoid lacewings is provided. The present finding reveals how the specialised foreleg armature associated to the raptorial lifestyle in extant mantidflies was present yet not fully established by the Early Cretaceous, at least in some lineages, and provides palaeontological evidence supporting certain evolutionary patterns of acquisition of integumentary specialisations related to the raptorial function in the group.

Description of a Bizarre New Genus and Species of Ambush Bugs from the Dominican Republic (Heteroptera: Reduviidae: Phymatinae)

AbstractEnigmatic and rarely collected, ambush bugs of the tribe Macrocephalini (Heteroptera: Reduviidae: Phymatinae) encompass a diverse group of predatory bugs armed with subchelate raptorial forelegs, a greatly enlarged scutellum, and elongate head. Macrocephalini is the most specious of the four tribes of ambush bugs, consisting of 20 genera and 154 species. They are represented in the Caribbean by several remarkable taxa that bear foretarsi, a trait unassociated with macrocephalines found elsewhere in the world. I here describe a new genus and species of Macrocephalini, Capricephala chiaroscuro gen. et sp. nov., native to the island of Hispaniola and one that bears striking differences to other phymatines known from that region.

A new Xenicocephalus species from Ecuador (Heteroptera, Enicocephalomorpha, Enicocephalidae).

Xenicocephalustomhenryisp. n. (Insecta: Hemiptera: Heteroptera: Enicocephalomorpha: Enicocephalidae) is established for a single macropterous female from Ecuador. The enigmatic genus now includes three species known from only two Neotropical adults and an incomplete female specimen. The new species is described and illustrated, extensive comparative diagnoses for Xenicocephalus species are provided, and nomenclature, distribution, and biology of the genus are reviewed. The architecture of the raptorial forelegs of Xenicocephalus is unique among Enicocephalomorpha, and the genus is classified as subfamily incertae sedis.

First observations on the life cycle and mass eclosion events in a mantis fly (Family Mantispidae) in the subfamily Drepanicinae.

BackgroundThe Mantispidae are a distinctive group of Neuroptera known for the adults’ possession of raptorial forelegs. There are four recognised, extant subfamilies of Mantispidae: the Mantispinae, Symphrasinae, Calomantispinae and Drepanicinae. The life history and larval behaviour of the subfamily Mantispinae is best known: the immatures are spider egg predators. Among the three remaining subfamilies, larval Symphrasinae and Calomantispinae most likely predate on other small arthropods, while the immature life history of Drepanicinae, until now, remained completely unknown.New informationHere we provide observations of annual, near-synchronised, mass emergences of adults of the drepanicine, Ditaxis biseriata (Westwood), within a well-established Macadamia orchard in northern New South Wales, Australia. A female deposited fertile eggs, allowing this first report of egg batch and first instar morphology. The mass emergence of mobile pharate adults from the ground was observed in the same month in two consecutive years. The pharates climbed tree-trunks for a distance before undergoing eclosion. The newly-hatched first instar larvae are campodeiform and prognathous; a typical morphology among Mantispidae. After hatching, they drop to the ground and burrow into soil. They are unpigmented and appear to lack stemmata. Together, the observations infer that the immature component of the life cycle takes place underground in forested habitats. If this feature is common among the Drepanicinae, it might explain why so little is known of the biology of the immature stages.

The oldest predaceous water bugs (Insecta, Heteroptera, Belostomatidae), with implications for paleolimnology of the Triassic Cow Branch Formation

AbstractA new genus and species of predaceous water bugs,Triassonepa solensisn. gen. n. sp., is described from the Triassic Cow Branch Formation of Virginia and North Carolina (USA) based on ~36 adult specimens and 51 nymphs. This species is the oldest known member of the extant family Belostomatidae. It is placed in a new genus based on the unique structure of the raptorial foreleg, in which the tarsus is elongate and opposed to the tibia + femur. The fossil record of this family is reviewed and the paleoenvironmental implications of the species assemblage preserved in the Cow Branch Formation are discussed.