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For over a century, the metapleural gland, an exocrine gland above the hind coxa, has been thought to be a unique structure for ants (Hymenoptera: Formicidae), and regarded as a catalyst for the ecological and evolutionary success of the family. This gland is one of the most researched exocrine glands in arthropods and its anatomy, ultrastructure, and chemistry are well documented. Herein, we describe an exocrine gland from the proctotrupoid wasp Pelecinus polyturator (Hymenoptera: Pelecinidae) with a similar position, structure, and chemistry to the ant metapleural gland: it is located just above the hind coxa, corresponds to an externally concave and fenestrated atrium, is composed of class 3 gland cells, and its extract contains relatively strong acids. We discover that the pelecinid gland is associated with the dilator muscle of the first abdominal spiracle, a trait that is shared with ants, but remained overlooked, possibly due to its small diameter, or obfuscation by the extensive metapleural gland. We also provide a biomechanical argument for passive emptying of the gland in both taxa. Pelecinids and ants with metapleural glands share a close association with soil. The pelecinid metapleural gland might therefore also have an antiseptic function as suggested for ants. We examined 44 other Hymenoptera families and found no glands associated with the oclusor apodeme or any signs of external modification. Our results strongly indicate that this complex trait (anatomical & chemical) evolved independently in ants and pelecinid wasps providing an exceptional system to better understand exocrine gland evolution in Hymenoptera. [ABSTRACT FROM AUTHOR]

Simple Summary: Soybean thrips are an important vector of Soybean vein necrosis virus disease, found in all soybean-growing regions of the United States and Canada. The disease reduces the seed oil content and fatty acid profiles in infected plants. It is important to know the morphology of the female reproductive system of soybean thrips to understand the egg-laying mechanism and develop strategies for virus vector management. For this purpose, we used fuchsin staining, paraffin-based histology, dissections, serial block-face scanning electron microscopy and confocal laser scanning microscopy techniques to understand the structure and motorization of the internal and external genitalia of soybean thrips. We also investigated the egg-laying behavior of soybean thrips. The female reproductive system is composed of two ovaries, an oviduct, an accessory gland, an appendage gland, a common oviduct and a vagina. Female soybean thrips lay eggs in the parenchymatous tissues near the veins of the leaves. The appendage gland likely secretes lubrication to facilitate the movement of eggs through the external genitalia. Seven muscles support the movement of eggs from the ovaries to the leaf surface. The anatomy and probable role of each muscle is also described. Soybean thrips (Neohydatothrips variabilis) are an important phytophagous vector of the widely recognized Soybean vein necrosis orthotospovirus (SVNV). Understanding the egg-laying behavior of these thrips could aid in developing strategies for the management of the vector and virus. In this study, we described the egg-laying behavior of N. variabilis and reconstructed the three-dimensional morphology of the female terminalia by using serial block-face scanning electron microscopy (SBFSEM) and confocal laser scanning microscopy (CLSM). The female reproductive system consists of two panoistic ovaries consisting of eight ovarioles. The appendage gland is connected to the ovaries by two muscles, and to the body wall by a single muscle. The spermatheca is connected to the eighth tergum through four branched muscles, to the basivalvulae of the ovipositor by one muscle and to the vagina by a single muscle. The external genitalia are operated by seven muscles. The movement of the eggs inside the ovipositor is achieved by the back and forth "rocking" movement of the first valvulae and valvifer. Eggs are deposited into the parenchymatous tissue alongside leaf veins. To the best of our knowledge, this is the first study describing the internal and external genitalia of N. variabilis. [ABSTRACT FROM AUTHOR]

Teleasinae are commonly collected scelionids that are the only known egg parasitoids of carabid beetles and therefore play a crucial role in shaping carabid populations in natural and agricultural ecosystems. We review the available host information of Teleasinae, report a new host record, and revise Gryonoides Dodd, 1920, a morphologically distinct teleasine genus. We review the generic concept of Gryonoides and provide diagnoses and descriptions of thirteen Gryonoides species and two varieties: G. glabriceps Dodd, 1920, G. pulchellus Dodd, 1920 (= G. doddi Ogloblin, 1967, syn. nov. and G. pulchricornis Ogloblin, 1967, syn. nov.), G. brasiliensis Masner & Mikó, sp. nov., G. flaviclavus Masner & Mikó, sp. nov., G. fuscoclavatus Masner & Mikó, sp. nov., G. garciai Masner & Mikó, sp. nov., G. mexicali Masner & Mikó, sp. nov., G. mirabilicornis Masner & Mikó, sp. nov., G. obtusus Masner & Mikó, sp. nov., G. paraguayensis Masner & Mikó, sp. nov., G. rugosus Masner & Mikó, sp. nov., G. uruguayensis Masner & Mikó, sp. nov. We treat Gryonoides scutellaris Dodd, 1920, as status uncertain. Gryonoides mirabilicornis Masner & Mikó, sp. nov. is the only known teleasine with tyloids on two consecutive flagellomeres, a well-known trait of Sparasionidae. An illustrated identification key to species of Gryonoides, a queryable semantic representation of species descriptions using PhenoScript, and a simple approach for making Darwin Core Archive files in taxonomic revisions accessible are provided. [ABSTRACT FROM AUTHOR]

The Waterston's evaporatorium (=Waterston's organ), a cuticular modification surrounding the opening of an exocrine gland located on metasomal tergite 6, is characterized and examined for taxonomic signifi- cance within the parasitoid wasp family Ceraphronidae. Modification of the abdominal musculature and the dorsal vessel are also broadly discussed for the superfamily Ceraphronoidea, with a novel abdominal pulsatory organ for Apocrita being discovered and described for the first time. Cuticular modification of T6, due to the presence of the Waterston's evaporatorium, provides a character complex that allows for genus- and species-level delimitation in Ceraphronidae. The matching of males and females of a species using morphology, a long standing challenge for the group, is also resolved with this new character set. Phylogenetic analysis including 19 Waterston's evaporatorium related characters provides support for current generic groupings within the Ceraphronidae and elaborates on previously suggested synapomorphies. Potential function of the Waterston's organ and its effects on the dorsal vessel are discussed. [ABSTRACT FROM AUTHOR]

Spalangiopelta is a small genus of chalcid wasps that has received little attention despite the widespread distribution of its extant species. The fossil record of the genus is restricted to a single species from Miocene Dominican amber. We describe two new fossil species, Spalangiopelta darlingi sp. n. and Spalangiopelta semialba sp. n. from Baltic amber. The species can be placed within the extant genus Spalangiopelta based on the distinctly raised hind margin of the mesopleuron. 3D models reconstructed from νCT data were utilized to assist in the descriptions. Furthermore, we provide a key for the females of all currently known Spalangiopelta species. The phylogenetic placement of the fossils within the genus is analyzed using parsimony analysis based on morphological characters. Phylogenetic and functional relevance of two wing characters, admarginal setae and the hyaline break, are discussed. The newly described Baltic amber fossils significantly extend the minimum age of Spalangiopelta to the Upper Eocene. [ABSTRACT FROM AUTHOR]

Morphometric research is being applied to a growing number and variety of organisms. Discoveries achieved via morphometric approaches are often considered highly transferable, in contrast to the tacit and idiosyncratic interpretation of discrete character states. The reliability of morphometric workflows in insect systematics has never been a subject of focused research, but such studies are sorely needed. In this paper, we assess the reproducibility of morphometric studies of ants where the mode of data collection is a shared routine.We compared datasets generated by eleven independent gaugers, that is, collaborators, who measured 21 continuous morphometric traits on the same pool of individuals according to the same protocol. The gaugers possessed a wide range of morphometric skills, had varying expertise among insect groups, and differed in their facility with measuring equipment. We used intraclass correlation coefficients (ICC) to calculate repeatability and reproducibility values (i.e., intra‐ and intergauger agreements), and we performed a multivariate permutational multivariate analysis of variance (PERMANOVA) using the Morosita index of dissimilarity with 9,999 iterations.The calculated average measure of intraclass correlation coefficients of different gaugers ranged from R = 0.784 to R = 0.9897 and a significant correlation was found between the repeatability and the morphometric skills of gaugers (p = 0.016). There was no significant association with the magnification of the equipment in the case of these rather small ants. The intergauger agreement, that is the reproducibility, varied between R = 0.872 and R = 0.471 (mean R = 0.690), but all gaugers arrived at the same two‐species conclusion. A PERMANOVA test revealed no significant gauger effect on species identity (R2 = 0.69, p = 0.58).Our findings show that morphometric studies are reproducible when observers follow the standard protocol; hence, morphometric findings are widely transferable and will remain a valuable data source for alpha taxonomy. [ABSTRACT FROM AUTHOR]

Phenotypic polymorphism can constitute an inherent challenge for species delimitation. This issue is exemplified in bumble bees (Bombus), where species can exhibit high colour variation across their range, but otherwise exhibit little morphological variation to distinguish them from close relatives. We examine the species status of one of the most abundant North American bumble bees, Bombus bifarius Cresson, which historically comprised two major taxa, bifarius s.s. and nearcticus. These lineages are recognized primarily by red and black variation in their mid‐abdominal coloration; however, a continuum from black (nearcticus) to red (bifarius s.s.) variation has led to their historic synonymization. Integrating mitochondrial and nuclear data and whole‐genome sequencing, we reveal a high level of both mitochondrial and nuclear divergence delimiting two morphologically cryptic species – the red bifarius s.s. and the colour‐variable (black to red) nearcticus. Population genomic analysis supports an absence of recent genomic admixture and a strong population structure between the two clades, even in sympatry. Species distribution models predict partially differentiated niches between the genetically inferred clades with annual precipitation being a leading differentiating variable. The bifarius s.s. lineage also occupies significantly higher elevations, with regions of sympatry being among the highest elevations in nearcticus. Our data also support a subspecies‐level divergence between the broadly distributed nearcticus and the island population vancouverensis. In this paper, we formally recognize the two species, Bombus bifarius Cresson and Bombus vancouverensis Cresson, the latter including the subspecies B. vancouverensis vancouverensiscomb.n. and B. vancouverensis nearcticuscomb.n., with vancouverensis the name bearer due to year priority. [ABSTRACT FROM AUTHOR]

This catalogue includes all valid family-group (six subtribes), genus-group (55 genera, 33 subgenera), and species-group names (1009 species and subspecies) of Sepidiini darkling beetles (Coleoptera: Tenebrionidae: Pimeliinae), and their available synonyms. For each name, the author, year, and page number of the description are provided, with additional information (e.g., type species for genus-group names, author of synonymies for invalid taxa, notes) depending on the taxon rank. Verified distributional records (loci typici and data acquired from revisionary publications) for all the species are gathered. Distribution of the subtribes is illustrated and discussed. Several new nomenclatural acts are included. The generic names Phanerotomea Koch, 1958 [= Ocnodes Fåhraeus, 1870] and Parmularia Koch, 1955 [= Psammodes Kirby, 1819] are new synonyms (valid names in square brackets). The following new combinations are proposed: Ocnodes acuductus acuductus (Ancey, 1883), O. acuductus ufipanus (Koch, 1952), O. adamantinus (Koch, 1952), O. argenteofasciatus (Koch, 1953), O. arnoldi arnoldi (Koch, 1952), O. arnoldi sabianus (Koch, 1952), O. barbosai (Koch, 1952), O. basilewskyi (Koch, 1952), O. bellmarleyi (Koch, 1952), O. benguelensis (Koch, 1952), O. bertolonii (Guérin-Méneville, 1844), O. blandus (Koch, 1952), O. brevicornis (Haag-Rutenberg, 1875), O. brunnescens brunnescens (Haag-Rutenberg, 1871), O. brunnescens molestus (Haag-Rutenberg, 1875), O. buccinator (Koch, 1952), O. bushmanicus (Koch, 1952), O. carbonarius (Gerstaecker, 1854), O. cardiopterus (Fairmaire, 1888), O. cataractus (Koch, 1952), O. cinerarius (Koch, 1952), O. complanatus (Koch, 1952), O. confertus (Koch, 1952), O. congruens (Péringuey, 1899), O. cordiventris (Haag-Rutenberg, 1871), O. crocodilinus (Koch, 1952), O. dimorphus (Koch, 1952), O. distinctus (Haag-Rutenberg, 1871), O. dolosus (Péringuey, 1899), O. dorsocostatus (Gebien, 1910), O. dubiosus (Péringuey, 1899), O. ejectus (Koch, 1952), O. epronoticus (Koch, 1952), O. erichsoni (Haag-Rutenberg, 1871), O. ferreirae ferreirae (Koch, 1952), O. ferreirae zulu (Koch, 1952), O. fettingi (Haag-Rutenberg, 1875), O. fistucans (Koch, 1952), O. fraternus (Haag-Rutenberg, 1875), O. freyi (Koch, 1952), O. freudei (Koch, 1952), O. fulgidus (Koch, 1952), O. funestus (Haag-Rutenberg, 1871), O. gemmeulus (Koch, 1952), O. gibberosulus (Péringuey, 1908), O. gibbus (Haag-Rutenberg, 1879), O. globosus (Haag-Rutenberg, 1871), O. granisterna (Koch, 1952), O. granulosicollis (Haag-Rutenberg, 1871), O. gridellii (Koch, 1960), O. guerini guerini (Haag-Rutenberg, 1871), O. guerini lawrencii (Koch, 1954), O. guerini mancus (Koch 1954), O. haemorrhoidalis haemorrhoidalis (Koch, 1952), O. haemorrhoidalis salubris (Koch, 1952), O. heydeni (Haag-Rutenberg, 1871), O. humeralis (Haag-Rutenberg, 1871), O. humerangula (Koch, 1952), O. imbricatus (Koch, 1952), O. imitator imitator (Péringuey, 1899), O. imitator invadens (Koch, 1952), O. inflatus (Koch, 1952), O. janssensi (Koch, 1952), O. javeti (Haag-Rutenberg, 1871), O. junodi (Péringuey, 1899), O. kulzeri (Koch, 1952), O. lacustris (Koch, 1952), O. laevigatus (Olivier, 1795), O. lanceolatus (Koch, 1953), O. licitus (Peringey, 1899), O. luctuosus (Haag-Rutenberg, 1871), O. luxurosus (Koch, 1952), O. maputoensis (Koch, 1952), O. marginicollis (Koch, 1952), O. martinsi (Koch, 1952), O. melleus (Koch, 1952), O. mendicus estermanni (Koch, 1952), O. mendicus mendicus (Péringuey, 1899), O. miles (Péringuey, 1908), O. mimeticus (Koch, 1952), O. misolampoides (Fairmaire, 1888), O. mixtus (Haag-Rutenberg, 1871), O. monacha (Koch, 1952), O. montanus (Koch, 1952), O. mozambicus (Koch, 1952), O. muliebris curtus (Koch, 1952), O. muliebris muliebris (Koch, 1952), O. muliebris silvestris (Koch, 1952), O. nervosus (Haag-Rutenberg, 1871), O. notatum (Thunberg, 1787), O. notaticollis (Koch, 1952), O. odorans (Koch, 1952), O. opacus (Solier, 1843), O. osbecki (Billberg, 1815), O. overlaeti (Koch, 1952), O. ovulus (Haag-Rutenberg, 1871), O. pachysoma ornata (Koch, 1952), O. pachysoma pachysoma (Péringuey, 1892), O. papillosus (Koch, 1952), O. pedator (Fairmaire, 1888), O. perlucidus (Koch, 1952), O. planus (Koch, 1952), O. pretorianus (Koch, 1952), O. procursus (Péringuey, 1899), O. protectus (Koch, 1952), O. punctatissimus (Koch, 1952), O. puncticollis (Koch, 1952), O. punctipennis planisculptus (Koch, 1952), O. punctipennis punctipennis (Harold, 1878), O. punctipleura (Koch, 1952), O. rhodesianus (Koch, 1952), O. roriferus (Koch, 1952), O. rufipes (Harold, 1878), O. saltuarius (Koch, 1952), O. scabricollis (Gerstaecker, 1854), O. scopulipes (Koch, 1952), O. scrobicollis griqua (Koch, 1952), O. scrobicollis simulans (Koch, 1952), O. semirasus (Koch, 1952), O. semiscabrum (Haag-Rutenberg, 1871), O. sericicollis (Koch, 1952), O. similis (Péringuey, 1899), O. sjoestedti (Gebien, 1910), O. spatulipes (Koch, 1952), O. specularis (Péringuey, 1899), O. spinigerus (Koch, 1952), O. stevensoni (Koch, 1952), O. tarsocnoides (Koch, 1952), O. temulentus (Koch, 1952), O. tenebrosus melanarius (Haag-Rutenberg, 1871), O. tenebrosus tenebrosus (Erichson, 1843), O. tibialis (Haag-Rutenberg, 1871), O. torosus (Koch, 1952), O. transversicollis (Haag-Rutenberg, 1879), O. tumidus (Haag-Rutenberg, 1871), O. umvumanus (Koch, 1952), O. vagus (Péringuey, 1899), O. vaticinus (Péringuey, 1899), O. verecundus (Péringuey, 1899), O. vetustus (Koch, 1952), O. vexator (Péringuey, 1899), O. virago (Koch, 1952), O. warmeloi (Koch, 1953), O. zanzibaricus (Haag-Rutenberg, 1875), Psammophanes antinorii (Gridelli, 1939), and P. mirei (Pierre, 1979). The type species [placed in square brackets] of the following genus-group taxa are designated for the first time, Ocnodes Fåhraeus, 1870 [Ocnodes scrobicollis Fåhraeus, 1870], Psammodophysis Péringuey, 1899 [Psammodophysis probes Péringuey, 1899], and Trachynotidus Péringuey, 1899 [Psammodes thoreyi Haag-Rutenberg, 1871]. A lectotype is designated for Histrionotus omercooperi Koch, 1955 in order to fix its taxonomic status. Ulamus Kamiński is introduced here as a replacement name for Echinotus Marwick, 1935 [Type species. Avicula echinata Smith, 1817] (Mollusca: Pteriidae) to avoid homonymy with Echinotus Solier, 1843 (Coleoptera: Tenebrionidae). [ABSTRACT FROM AUTHOR]

Ceraphronoids are some of the most commonly collected hymenopterans, yet they remain rare in the fossil record. Conostigmus talamasi Mikó and Trietsch, sp. nov. from Baltic amber represents an intermediate form between the type genus, Megaspilus, and one of the most species-rich megaspilid genera, Conostigmus. We describe the new species using 3D data collected with synchrotron-based micro-CT equipment. This non-invasive technique allows for quick data collection in unusually high resolution, revealing morphological traits that are otherwise obscured by the amber. In describing this new species, we revise the diagnostic characters for Ceraphronoidea and discuss possible reasons why minute wasps with a pterostigma are often misidentified as ceraphronoids. Based on the lack of ceraphronoid characteristics, we remove Dendrocerus dubitatus Brues, 1937, Stigmaphronidae, and Radiophronidae from Ceraphronoidea and consider them as incertae sedis. We also provide some guidance for their future classification. [ABSTRACT FROM AUTHOR]

Background Male genitalia phenotypes of Ceraphron (Jurine, 1807) are informative for species delimitation, but due to their minute size, these characters have not been used extensively. Recent developments in visualisation techniques, e.g. confocal laser scanning microscopy and high resolution bright field imaging, allow for more thorough examination of these minute anatomical structures and the development of a robust, male genitalia-based taxonomic system. We also establish a character set, a template, that will facilitate future revisions of these wasps. New information Ceraphron krogmanni sp. nov. is described with outsized male genitalia and multiple diagnostic traits that are unique amongst Ceraphron species. [ABSTRACT FROM AUTHOR]

All Ceraphronoidea have metasomal patches of translucent cuticle and setae that have never been investigated before, despite their potential behavioral and phylogenetic relevance. To understand the internal and external morphology of these structures, specimens were examined using a broad array of histology-based methods, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and serial block-face scanning electron microscopy (SBFSEM). For the first time, the setiferous patches are shown to be associated with exocrine glands in Ceraphronoidea. The proposed glandular function is the secretion of pheromones, with the setae above the pore openings serving as a surface for evaporation. The translucent cuticle is morphologically distinct from the setiferous patches; structures resembling lamellar bodies were found underneath the translucent cuticle, and may be associated with photoreceptors or endocrine glands. The locations of translucent cuticle on the metasoma are unique to different families and genera within Ceraphronoidea, and could be useful for inferring phylogenetic relationships. The character distribution suggests that the genera Trassedia and Masner are more closely related to Ceraphronidae than Megaspilidae. We found similar structures containing translucent cuticle in Orussidae and Ichneumonoidea, indicating that these structures are potentially a rich character system for future phylogenetic analysis in Hymenoptera. [ABSTRACT FROM AUTHOR]

Thickened femora of insects are correlated to enlarged muscle masses and serve two basic purposes: jumping/kicking and grasping/holding. Modifications on the ventral femoral wall and the tibial flexor tendon that are possibly involved in catch mechanisms have been described in multiple insect taxa with both jumping and grasping legs. Our comparative study aims to explore the functional and structural similarities of these modification in jumping and grasping leg types from Coleoptera, Hymenoptera, Diptera, and Orthoptera with the combination of cutting edge, noninvasive imaging methods, and classical dissections techniques. Our data indicate that locking mechanisms are present in the jumping and grasping legs of insects. We describe three femoro-tibial lock types based on the location of the interacting sclerites relative to the site of origin of the tibial flexor tendon. All of the three types can be found in jumping insect legs, whereas only one type is present in grasping legs. The locking mechanism might aid in keeping the femoro-tibial joint in a flexed position for an extended period of time. Our data indicate that morphologically similar modifications in the femoro-tibial joint are involved in energy-saving mechanisms both in jumping and grasping legs in insects. [ABSTRACT FROM AUTHOR]

Among some of the most unusual traits of the gasteruptiid wasps is their unique hovering flight and the expansion of their hind tibiae. Tibial expansions in female parasitoid hymenopterans often involve an enlarged sensory structure for vibration detection, the subgenual organ, thus enabling refined substrate-borne detection of concealed hosts. In the present paper, we utilize a combination of microscopy, chemical analysis, gene expression, and behavior to explore the function of the expanded hind tibia of gasteruptiid wasps. We find that the expanded hind tibia of gasteruptiids is filled largely with fat body, a cell cluster thought not typically to occur in insect legs. Based on its position relative to flexible tibial structures and the subgenual organ, the gasteruptiid tibial fat body may function to amplify vibrational signals. We show the tibial fat body to be filled with both trophocytes and, depending on gasteruptiid lineage, oenocytes. Transcriptomics reveals enrichment for fat-related genes more than expected in an insect leg and raises several additional possibilities for functions of fat in the leg including detoxification. Finally, our flight observations support the hypothesis that this structure may also function in balance and maneuvering in the unusual leg-dangling flight behavior of this wasp. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pheromone components detected in male pleural epidermal cells and rectum. • Pleural epidermal cells are 100 times larger in males (300–400 μm) than females. • In males, pleural epidermal calls are multinucleated, suggesting polyploidization. • Males have cuticular elements that may help release pheromone through cuticle. Eurosta solidaginis males produce large amounts of putative sex pheromone compared to other insect species; however, neither the site of pheromone production nor the release mechanism has been characterized. We compared E. solidaginis males and females, focusing on sexually dimorphic structures that are known to be involved in pheromone production in other tephritid species. Morphological and chemical analyses indicated that the rectum and pleural epidermis are involved in male E. solidaginis pheromone production, storage, or emission. We detected large quantities of pheromone in the enlarged rectum, suggesting that it stores pheromone for subsequent release through the anus. However, pheromone might also discharge through the pleural cuticle with the involvement of unusual pleural attachments of the tergosternal muscles, which, when contracted in males, realign specialized cuticular surface elements and expose less-sclerotized areas of cuticle. In males, pheromone components were also detected in epidermal cells of the pleuron. These cells were 60–100 times larger in mature males than in females and, to our knowledge, are the largest animal epithelial cells ever recorded. Furthermore, because these large cells in males are multinucleated, we presume that they develop through somatic polyploidization by endomitosis. Consequently, the pheromone-associated multinuclear pleural epidermal cells of Eurosta solidaginis may provide an interesting new system for understanding polyploidization. [ABSTRACT FROM AUTHOR]