Sting Apparatus Research Articles

Morphology of the sting apparatus in sapygid wasps of the subfamily Sapyginae (Hymenoptera: Sapygidae)

Sapygidae is a small family of Aculeata (Hymenoptera), which is divided into two subfamilies Fedtschenkiinae and Sapyginae. The morphology of the skeleton of the sting apparatus in some European species of Sapyginae, which are kleptoparasites of wild bees from the families Megachilidae, Apidae and Colletidae, was examined. Significant differences in its skeletal structure were noted between Sapygina decemguttata and representatives of the genera Sapyga and Monosapyga. The sting of Sapygina belongs to the decurved type, while Sapyga and Monosapyga have a sting close to the coiled type. A comparison of the structure of the skeletons of the sting apparatuses of Sapygina and Sapyga with that of Fedtschenkia (according to other authors) was made. The similarity of the structure of the sting apparatuses of Sapygina and Fedtschenkia was noted. The possibility of using the Sapyginae sting as an ovipositor is discussed.

Bee morphology: A skeletomuscular anatomy of Thyreus (Hymenoptera: Apidae).

Although the knowledge of the skeletal morphology of bees has progressed enormously, a corresponding advance has not happened for the muscular system. Most of the knowledge about bee musculature was generated over 50 years ago, well before the digital revolution for anatomical imaging, including the application of microcomputed tomography. This technique, in particular, has made it possible to dissect small insects digitally, document anatomy efficiently and in detail, and visualize these data three dimensionally. In this study, we document the skeletomuscular system of a cuckoo bee, Thyreus albomaculatus and, with that, we provide a 3D atlas of bee skeletomuscular anatomy. The results obtained for Thyreus are compared with representatives of two other bee families (Andrenidae and Halictidae), to evaluate the generality of our morphological conclusions. Besides documenting 199 specific muscles in terms of origin, insertion, and structure, we update the interpretation of complex homologies in the maxillolabial complex of bee mouthparts. We also clarify the complicated 3D structure of the cephalic endoskeleton, identifying the tentorial, hypostomal, and postgenal structures and their connecting regions. We describe the anatomy of the medial elevator muscles of the head, precisely identifying their origins and insertions as well as their homologs in other groups of Hymenoptera. We reject the hypothesis that the synapomorphic propodeal triangle of Apoidea is homologous with the metapostnotum, and instead recognize that this is a modification of the third phragma. We recognize two previously undocumented metasomal muscle groups in bees, clarifying the serial skeletomusculature of the metasoma and revealing shortcomings of Snodgrass' "internal-external" terminological system for the abdomen. Finally, we elucidate the muscular structure of the sting apparatus, resolving previously unclear interpretations. The work conducted herein not only provides new insights into bee morphology but also represents a source for future phenomic research on Hymenoptera.

Exploring Honeybee Abdominal Anatomy through Micro-CT and Novel Multi-Staining Approaches.

Simple SummaryApis mellifera or western honeybees are insects belonging to the Order Hymenoptera and the most important pollinators worldwide with great implications in natural biodiversity and agriculture due to their importance in pollination and honey production. The characterization of honeybee anatomy with precise tools will allow a better comprehension of the physiology of these insects under different biological conditions. Here, we employed Micro-computed tomography and novel staining methods to define the morphoanatomical characteristics of the worker honeybee abdomen. We defined the 3D and 2Ds structures of the midgut and hindgut and discovered a new cell type called ventricular telocyte, with possible roles in honeybee epithelium maintenance. Overall, we propose that this method will be useful for further investigation of the structure of the honeybee abdomen under a wide variety of environmental conditions.Continuous improvements in morphological and histochemical analyses of Apis mellifera could improve our understanding of the anatomy and physiology of these insects at both the cellular and tissue level. In this work, two different approaches have been performed to add new data on the abdomen of worker bees: (i) Micro-computed tomography (Micro-CT), which allows the identification of small-scale structures (micrometers) with adequate/optimal resolution and avoids sample damage and, (ii) histochemical multi-staining with Periodic Acid-Schiff-Alcian blue, Lactophenol-Saphranin O and pentachrome staining to precisely characterize the histological structures of the midgut and hindgut. Micro-CT allowed high-resolution imaging of anatomical structures of the honeybee abdomen with particular emphasis on the proventriculus and pyloric valves, as well as the connection of the sting apparatus with the terminal abdominal ganglia. Furthermore, the histochemical analyses have allowed for the first-time description of ventricular telocytes in honeybees, a cell type located underneath the midgut epithelium characterized by thin and long cytoplasmic projections called telopodes. Overall, the analysis of these images could help the detailed anatomical description of the cryptic structures of honeybees and also the characterization of changes due to abiotic or biotic stress conditions.

Histology and ultrastructure of glands associated with the sting apparatus of the swarm-founding wasp Protopolybia exigua (Hymenoptera: Vespidae: Polistinae)

Social insects present a great diversity of exocrine glands, which are linked to fundamental roles of social life, and their morphological characterization represents the first step toward the knowledge of their function. We here describe the exocrine glands present in the sting apparatus of queens and workers of the wasp Protopolybia exigua. Histological analysis of serial sections under light microscopy revealed a glandular epithelium in the spiracular plate, the quadrate plate, and the gonostyli, while the last two in addition also contain clusters of class-3 cells. A big cluster of class-3 cells was also found in the oblong plate of some workers and queens. These findings reveal that a variety of glands, in addition to the common venom gland and Dufour gland, are present in association with the sting apparatus, of which three glands are novel reports for the exocrine repertoire of social insects. The position of the glands suggests a role in lubrication to provide mobility of the sting and venom ejection and/or participation in alarm behavior, while a function related to reproduction is also possible. The peculiar characteristics displayed by swarm-founding wasps are linked with exocrine gland secretions, making their investigation in Epiponini wasps a vast and interesting field.

Revealing diagnostic characters through morphological evolution in cleptoparasitic spider wasps (Hymenoptera, Pompilidae, Ceropales)

AbstractSpider wasps (Hymenoptera: Pompilidae) cleptoparasites, such as Ceropales Latreille, have evolved the ability to steal the spiders from other pompilids. This behaviour is often observed with morphological adaptations that might mislead taxonomic decisions due to convergence. For instance, four subgenera, Bifidoceropales Wolf, Ceropales s. str., Hemiceropales Wolf and Priesnerius Móczár and six species‐groups are recognized within Ceropales; all with doubtful identification. We studied species of Ceropales in light of molecular and morphological characters to delimit lineages and to test the applicability of morphological traits in diagnosing them. We used the molecular nuclear markers long‐wavelength rhodopsin and 28S ribosomal RNA, and the mitochondrial Cytochrome C Oxidase I available at Genebank to reconstruct Bayesian and maximum likelihood phylogenetic trees. Our results disagree with the current subgeneric classification. We found that fore wing venation and the shape of the female posterior metasomal segments are key characters to differentiate lineages. We discuss morphological evolution of the sting apparatus using ancestral state reconstructions; and we propose Bifidoceropales as a junior subjective synonym of Ceropales s. str., whereas Priesnerius, stat. resurr. and Hemiceropales are redefined based on male and female morphological traits. This study raises important concerns, from the validity of diagnostic characters currently used to identify cleptoparasite spider wasps—and taxa with habitat constraints leading to homoplasies. Taxonomy can benefit from the reconstruction of ancestral traits by revealing reliable diagnostic characters. Moreover, our investigation provides a framework for evolutionary studies on hymenopteran cleptoparasitoids and sets the basis for future phylogenomic investigations on Ceropales by opening new perspectives for taxonomic acts and guiding taxonomic sampling efforts.

Total-evidence dating and morphological partitioning: a novel approach to understand the phylogeny and biogeography of augochlorine bees (Hymenoptera: Apoidea)

Abstract Augochlorini comprise 646 described bee species primarily distributed in the Neotropical region. According to molecular and morphological phylogenies, the tribe is monophyletic and subdivided into seven genus groups. Our main objective is to propose a revised phylogeny of Augochlorini based on a comprehensive data set including fossil species as terminals and new characters from the internal skeleton. We also aim to develop a total-evidence framework incorporating a morphological-partitioned homoplasy approach and molecular data and propose a detailed biogeographic and evolutionary scenario based on ancestor range estimation. Our results recovered Augochlorini and most genus groups as monophyletic, despite some uncertainties about monophyly of the Megalopta and Neocorynura groups. The position of the cleptoparasite Temonosoma is still uncertain. All analyses recovered Augochloropsis s.l. as related to the Megaloptidia group. Internal characters from the head, mesosoma and sting apparatus provided important synapomorphies for most internal nodes, genus groups and genera. Augochlorini diversification occurred in the uplands of the Neotropical region, especially the Brazilian Plateau. Multiple dispersals to Amazonia, Central America and North America with returns to the Atlantic endemism area were recovered in our analysis. Total evidence, including morphological partitioning, was shown to be a reliable approach for phylogenetic reconstruction.

Linking the Morphology of Sternal Glands to Rubbing Behavior by Vespa soror (Hymenoptera: Vespidae) Workers During Recruitment for Group Predation.

The activities of social insect colonies are supported by exocrine glands and the tremendous functional diversity of the compounds that they secrete. Many social wasps in the subfamilies Vespinae and Polistinae have two sternal glands—the van der Vecht and Richards’ glands—that vary in their features and function across the species in which they are found. Field observations suggest that giant hornets use secretions from the van der Vecht gland to chemically mark targeted nests when workers initiate group attacks on social insect prey. However, descriptions of giant hornets’ sternal glands and details about their recruitment behavior are lacking. We describe the morphology of the sternal glands of the giant hornet Vespa soror du Buysson and consider their potential to contribute to a marking pheromone. We also assess the gastral rubbing behavior of workers as they attacked Apis cerana F. (Hymenoptera: Apidae) colonies. V. soror workers have well-developed van der Vecht and Richards’ glands on their terminal gastral sternites, with morphologies that robustly support the synthesis, storage, and dissemination of their secretory products. Observations confirm that the van der Vecht gland is exposed during gastral rubbing, but that the Richards’ gland and glands associated with the sting apparatus may also contribute to a marking pheromone. Workers briefly but repeatedly rubbed their gasters around hive entrances and on overhead vegetation. Colonies were heavily marked over consecutive attacks. Our findings provide insight into the use of exocrine secretions by giant hornets as they recruit nestmates to prey colonies for group attacks.

Assessment of the In Vivo and In Vitro Release of Chemical Compounds from Vespa velutina.

Vespa velutina has been rapidly expanding throughout Galicia since 2012. It is causing human health risks and well-known losses in the beekeeping sector. Control methods are scarce, unspecific, and ineffective. Semiochemicals are insect-derived chemicals that play a role in communication and they could be used an integrated pest management tool alternative to conventional pesticides. A previous determination of the organic chemical profile should be the first step in the study of these semiochemicals. HS-SPME in living individuals and the sting apparatus extraction followed by GC-MS spectrometry were combined to extract a possible profile of these compounds in 43 hornets from Galicia. The identified compounds were hydrocarbons, ketones, terpenes, and fatty acid, and fatty acid esters. Nonanal aldehyde appeared in important concentrations in living individuals. While pentadecane, 8-hexyl- and ethyl oleate were mainly extracted from the venom apparatus. Ketones 2-nonanone, 2-undecanone and 7-nonen-2-one, 4,8-dimethyl- were identified by both procedures, as was 1,7-Nonadiene, 4,8-dimethyl-. Some compounds were detected for the first time in V. velutina such as naphthalene, 1,6-dimethyl-4-(1-methylethyl). The chemical profile by caste was also characterized.

United States port interceptions and predicted climate suitability of the red dwarf honeybee, Apis florea (Hymenoptera: Apidae), with notes on its identification

We analyzed the port interceptions of the red dwarf honeybee, Apis (Micrapis) florea and undetermined species of Apis from regions where the A. florea is present. We also provide information on the potential distribution of this species globally and for the USA by using two climatic suitability models: Plant Hardiness Zones and Maxent. The results show several significant interceptions at US ports of entry in the last 10 years, including complete colonies associated with sea containers. In addition, the climatic models showed suitable areas in warmer regions of the world, and Southern and Western USA. Finally, we provide some additional notes for the diagnosis of the females and males of A. florea, including some novel characters from the gonangulum and the sting blades, both parts of the complex sting apparatus of the workers.

Palynological Characterization of Stingless Bee Tetragonula iridipennis Smith (Hymenoptera: Apidae: Meliponini) Honey from Chotanagpur Plateau, Eastern India

Tetragonula iridipennis, belonging to the family Apidae under subfamily Apinae, are known as stingless bees as they do not have sting apparatus (Rasmussen, 2013; Muthuraman et al., 2013). They are ...

Comparative morphology of the musculature of the sting apparatus in Ampulex compressa (Hymenoptera, Ampulicidae) and Sceliphron destillatorium (Hymenoptera, Sphecidae)

The sting apparatus of aculeate Hymenoptera is derived from the ovipositor and is their most prominent apomorphy. In contrast to the frequently analysed sclerites of the sting apparatus, the associated musculature has largely been neglected. In this study, we use micro-computed tomography to present a detailed description of the musculature of the sting apparatus ofAmpulex compressa(Ampulicidae) andSceliphron destillatorium(Sphecidae). We found that 12 of 15 muscles corresponding to the sting apparatus are homologous between both species examined and 13 muscles in comparison with Hymenoptera described in the literature. All muscles identified as critical for the act of stinging were found in both species. Moreover, we found the ventral tergum 8-tergum 9 muscle and the tergum 8-tergum 8 muscles inA. compressaand the second valvifer-second valvifer muscle inS. destillatorium. For the first time, we describe the ventral tergum 8-tergum 9 muscle and the second valvifer-second valvifer muscle that interconnects both body sides, in Hymenoptera.

Morphology of sting apparatus of Chrysidoidea (Hymenoptera, Aculeata)

The main synapomorphy for Aculeata is the sting apparatus, which allows the female to envenom potential prey or hosts. The sting is the modified ovipositor which is not used for laying eggs anymore. Here, we explore the morphology of the sting apparatus within the families of Chrysidoidea. 27 skeletal structures were recognized, including three (dp1vf, dorsal projection of first valvifer; ppa, projection of posterior area of the second valvifer; vl9, ventral lap of tergite 9) that have not been observed previously, and 13 pairs of muscles, including four (superior dorsal T9-2vf (M5); inferior dorsal T9-2vf (M6); postero-lateral T9-2vf/mbr (M9); anterolateral 2vf/bl-2vv/fu (M11)) that have not been observed previously. Very conserved morphological patterns were observed; character support in the sting apparatus was found at the subfamily level, and within three families at the genus level. In addition, we describe the variation within the sting apparatus structures and musculature, propose evolutionary hypotheses about the function and evolution of the structures, and summarize phylogenetic conclusions for Chrysidoidea.

Formigas como recurso alimentar e medicinal

Este texto traz uma revisão dos artigos que descrevem a importância das formigas para humanos no aprovisionamento alimentar e no tratamento de doenças, aspectos que vão além do suporte aos serviços ambientais que estes animais realizam. Reunimos e atualizamos as informações a respeito do uso das formigas como recurso alimentar e medicinal por comunidades nativas indígenas e rurais no Brasil, na América Latina e em outros continentes. Os resultados compilados do presente estudo demonstram que a mirmecofagia é ainda amplamente empregada em vários locais do mundo, sendo uma fonte nutricional importante. Ao todo, foram registradas 52 espécies de formigas utilizadas como alimento. Quanto ao uso medicinal, foram registradas, até o presente momento, 19 espécies de formigas. Além das propriedades antifúngicas e antibacterianas dos hormônios produzidos pelas glândulas mandibular e metapleural, existem os hidrocarbonetos cuticulares, bem como as secreções da glândula de veneno e das glândulas associadas ao aparelho de ferrão que produzem substâncias químicas com aplicações em problemas estomacais, respiratórios, circulatórios e também nas hemorragias, artrites e dores em geral. Assim, abordamos dois aspectos da interação formigas/humanos e destacamos o histórico do seu uso no Brasil.

Morphology and chemical composition of the Koschewnikow gland of the honey bee Apis mellifera (Hymenoptera: Apidae) workers engaged in different tasks

The Koschewnikow gland is associated with the sting apparatus in the honey bee Apis mellifera Linnaeus, 1758, as a potential source of compounds used as an alarm pheromone. This study describes the histology, morphometry and ultrastructure, and chemical composition of the Koschewnikow gland in workers performing different tasks in the A. mellifera colony. The Koschewnikow gland shows well-developed globular secretory cells of class III with those of the nurse and foragers larger and in greater numbers than those of guard bees. At the ultrastructural level, the secretory cells of all worker bees are rich in mitochondria and smooth endoplasmic reticulum. Mitochondria had different ultrastructure among workers with membrane electron-dense granules in nurse and the electron-lucent halo surrounding the organelle in guard bees. Mitochondria in forager workers show degenerative features such as the disappearance of cristae, electron-lucent matrix, and accumulation of electron-dense aggregates. The chemical analyses of the Koschewnikow gland extract showed that of 23 compounds, 13 had different abundances between workers and of these, 10 were found in higher abundance in guard workers. These results suggest that the Koschewnikow gland has a different structure and chemical composition in honey bee workers engaged in different tasks.

Unveiling the morphology of the Oriental rare monotypic ant genus Opamyrma YAMANE, BUI & EGUCHI, 2008 (Hymenoptera: Formicidae: Leptanillinae) and its evolutionary implications, with first descriptions of the male, larva, tentorium, and sting apparatus

The monotypic genus Opamyrma Yamane, Bui & Eguchi, 2008 (Hymenoptera, Formicidae, Leptanillinae) is an extremely rare relictual lineage of apparently subterranean ants, so far known only from a few specimens of the worker and queen from Ha Tinh in Vietnam and Hainan in China. The phylogenetic position of the genus had been uncertain until recent molecular phylogenetic studies strongly supported the genus to be the most basal lineage in the cryptic subterranean subfamily Leptanillinae. In the present study, we examine the morphology of the worker, queen, male, and larva of the only species in the genus, Opamyrma hungvuong Yamane, Bui & Eguchi, 2008, based on colonies newly collected from Guangxi in China and Son La in Vietnam, and provide descriptions and illustrations of the male, larva, and some body parts of the worker and queen (including mouthparts, tentorium, and sting apparatus) for the first time. The novel morphological data, particularly from the male, larva, and sting apparatus, support the current phylogenetic position of the genus as the most basal leptanilline lineage. Moreover, we suggest that the loss of lancet valves in the fully functional sting apparatus with accompanying shift of the venom ejecting mechanism may be a non-homoplastic synapomorphy for the Leptanillinae within the Formicidae.Open access, licensed under CC BY 4.0. © 2020 The Author(s).DOI: 10.25849/myrmecol.news_030:027Pages: 27-52Volume: 30Year: 2020Journal: Myrmecol. News

Proteomic analysis of the venom of the social wasp Apoica pallens (Hymenoptera: Vespidae)

Wasps are a diverse group of insects that possess a sting apparatus associated with a venom gland, which is used for predation and colony defense. The biochemistry of Hymenoptera venom has been evaluated in relation to allergy and immunology, and proteomics has been shown to be a powerful tool for the identification of compounds with pharmacological potential. Data on wasps venom the of genus Apoica are scarce, so the objective of the present work was to identify the venom proteins of the eusocial wasp Apoica pallens, as a first step towards further investigation of applied uses of the venom and its protein constituents. The venom proteins were separated by two-dimensional gel electrophoresis, followed by MALDI-TOF/TOF mass spectrometry. A total of 259 spots were detected, with molecular weights from 4.9 to 141kDa. Thirty of these proteins were identified and classified into eight functional categories: allergen, enzyme, metabolism, structural, environmental response, proteoglycan, active in DNA and RNA, and unknown function. Due to the few available proteomic data for wasp venom, many proteins could not be identified, which makes studies with proteomic analysis of Hymenoptera venom even more important.

Morphology and Histochemistry of the Venom Apparatus in Different Castes of the Ant Ectatomma vizottoi (Formicidae: Ectatomminae)

The elimination of toxins via a venom gland by some ant species is a component of a larger mechanism for capturing prey and defense. The present study describes the morphology and histochemistry of the venom apparatus of different castes of the ant Ectatomma vizottoi Almeida, 1987. Morphologically, the venom apparatus of queens, gynes and workers of E. vizottoi are similar and composed of the sting apparatus and three distinct portions: two secretory portions (convoluted gland and secretory filament), and a storage portion (reservoir) - a hollow sting apparatus covered in the terminal portion of the reservoir by a sclerotized cuticle. The venom gland of E. vizottoi is longer in queens and gynes than in workers. Furthermore, the epithelium of the convoluted gland is taller in the glands of queens and gynes than in workers, which may be indicative of greater toxin synthesis, or may be related to different body sizes of the castes. The morphology and histology of the venom apparatus reflect those of a generalist, while the histochemical tests indicated that this structure has the same chemical content of lipids, proteins and polysaccharides among queens, gynes, and workers. Images obtained by confocal microscopy and scanning electronic microscopy reveal a muscle layer surrounding the reservoir that is interlaced with secretory filaments, which fixes, in a manner, the filaments in place. This musculature serves to eject stored venom, which likely leads to greater success in defense or foraging.

Functional morphology of the sting apparatus of the spider wasp Cryptocheilus versicolor (Scopoli, 1763) (Hymenoptera: Pompilidae)

AbstractThe females of the spider wasps (Hymenoptera: Pompilidae) hunt spiders to provision their larvae. The genital structures of pompilid females are modified in a sting that is used for paralyzing the prey (spiders) and defense. The skeleto‐muscular structure of the sting apparatus of a typical representative of the family (Cryptocheilus versicolor) is examined. The shape of sclerites, their relative positions and articulations are described. Some morphological adaptations are described for the first time. The wide anal arc of the tergum IX provides a stiff support for the muscles that move the valvulae. The resilin structures in the areas of articulation support the work of muscles and in some cases replace them. The 1st valvulae form a venom duct along their entire length, which provides the delivery of the venom to a specific point. An unpaired flap in the venom duct provides a dose of venom in the sting. This mechanism probably enhances the speed and accuracy of the wasp's sting movements. Functions of muscles and interactions of the structures of the sting apparatus of C. versicolor are discussed.

Proteomic analysis in the Dufour's gland of Africanized Apis mellifera workers (Hymenoptera: Apidae).

The colony of eusocial bee Apis mellifera has a reproductive queen and sterile workers performing tasks such as brood care and foraging. Chemical communication plays a crucial role in the maintenance of sociability in bees with many compounds released by the exocrine glands. The Dufour’s gland is a non-paired gland associated with the sting apparatus with important functions in the communication between members of the colony, releasing volatile chemicals that influence workers roles and tasks. However, the protein content in this gland is not well studied. This study identified differentially expressed proteins in the Dufour’s glands of nurse and forager workers of A. mellifera through 2D-gel electrophoresis and mass spectrometry. A total of 131 spots showed different expression between nurse and forager bees, and 28 proteins were identified. The identified proteins were categorized into different functions groups including protein, carbohydrate, energy and lipid metabolisms, cytoskeleton-associated proteins, detoxification, homeostasis, cell communication, constitutive and allergen. This study provides new insights of the protein content in the Dufour’s gland contributing to a more complete understanding of the biological functions of this gland in honeybees.

Convoluted and venom glands of different species of wasps

The social Hymenoptera increasingly arouse the attention of researchers due to the great economic and ecological importance to the species belonging to this order. The processes of pollination performed by these insects, the biological control, the structures of nests and colonies, the social organization, the accidents arising from their stings and the pharmacological potential of venoms synthesized by them, represent some of the features that make these individuals, targets of important studies. The sting apparatus and venom represent fundamental defense mechanisms of these insects. In order to characterize the convoluted and the venom gland of these species and gain an understanding of the relationship between the components, this study aimed to analyze through morphology and histochemical techniques the venom glands of the wasps, Polistes versicolor , Agelaia palipes palipes and Polybia paulista , and also the convoluted gland - a structure found in the reservoir, establishing the defining characteristics of these structures. In addition to the morphological features described about these structures, our results showed the presence of secretion produced by the convoluted gland cells which indicates that this structure contributes to the final composition of the venom produced and stored in the reservoir.