Crabronid wasps (Hymenoptera: Crabronidae) are ecologically important predators that provide various ecological services by regulating the arthropod populations, enhancing soil processes through nesting, serving as sensitive indicators of habitat condition, and providing pollen transfer for plants. However, as other invertebrates face biodiversity threats, these wasps might be under threat from environmental changes, and we need to assess the biodiversity patterns of these wasps in Yunnan Province. Unfortunately, no information is currently available about the pattern and factors responsible for the assemblages of these wasps within our study region. This study provides the first province-level assessment of habitat suitability, species richness, assemblage structure, and environmental determinants for Crabronidae in Yunnan by integrating species distribution modeling (SDM), multivariate clustering, and ordination analyses. More than 50 species were studied to assess habitat suitability in Yunnan using MaxEnt. Model performance was robust (AUC > 0.7). Suitability patterns varied distinctly among regions. Species richness peaked in southern Yunnan, particularly in the counties of Jinghong, Mengla, Menghai, and Jiangcheng Hani & Yi. Land use/land cover (LULC) variables were the dominant predictors for 90% of species, whereas precipitation-related variables contributed most strongly to the remaining 10%. Ward's hierarchical clustering grouped the 125 counties into three community assemblage zones, with Zone III comprising the most significant area. A unique species composition was found within a particular zone, and clear separation among zones based on environmental variation was supported by Principal Component Analysis (PCA), which explained more than 70% variability among zones. Furthermore, Canonical Correspondence Analysis (CCA) indicated that both LULC and climatic factors shaped community structure assemblages, with axes 1 and 2 explaining 70% of variance (p = 0.001). The most relevant key factors in each zone were precipitation variables (bio12, bio14, bio17), which were dominant in Zone I; for Zone II, temperature and vegetation variables were most important; and urban, wetland, and water variables were most important in Zone III.

The checklist of Iraqi Crabronid wasps has been updated due to this work. A total of 67 species are listed belonging to 29 genera, across 10 tribes within five subfamilies. The species distribution is also provided, and an identification key was developed to differentiate the high taxa.

Abstract A study was conducted to document the nesting behaviour and prey composition of a crabronid wasp, Trypoxylon sp. The wasp was molecularly characterised as T. clavicerum (NCBI Accession No. OQ913679.1). Nest acceptance rate was significantly higher in the reeds of Ipomea carnea (79.20%) and bamboo (84.80%). The mean number of brood cells (4.40 ± 0.89 cells/nest) and vestibular cells (1.06 cells/nest) built by the wasp was significantly higher in the reeds of I. carnea. Brood parasitisation by the nest parasite Amobia sp. was significantly higher in nests built by the wasp in paper straws (58.57%) compared to the nests built in the reeds of bamboo (23.33%). The mean durations of the egg, larval and pupal stages of T. clavicerum were 2.60 ± 0.55, 6.01 ± 0.71 and 4.80 ± 0.84 days. The number of nests recovered was observed to be the highest during the months of August (3.66 ± 1.53 nests), September (5.00 ± 4.36 nests), October (8.67 ± 2.89 nests) and November (6.00 ± 2.10 nests). The major species of spider from the occupied nests belonged to two families, viz. Salticidae (81%) and Oxyopidae (19%). During the nesting period the adult wasp provisioned a greater number of spiderlings (3.25 to 3.60 spiderlings/cell) than adult spiders (1.20 to 1.60 adult spiders/cell) to her brood. The time taken to complete a single nest provisioned with adult spiders and spiderlings (13.20 ± 6.83 hr/single nest) was significantly less than for the nests provisioned with adult spiders (46.80 ± 14.80 hr/single nest) only. This study is the first ever report of nesting behaviour and prey composition of the spider-hunting wasp T. clavicerum from India.

Thyridanthrax fenestratus (Fallén, 1814) is a bombyliid with poorly understood biology. It was recently shown to locally but frequently parasitize Pemphredon fabricii (M. Müller, 1911) (Hymenoptera: Crabronidae), a crabronid wasp that abundantly nests in old Lipara-induced galls on the common reed Phragmites australis (Cav.) Trin. ex Steud., 1840. The parasitism modes in Bombyliidae and Thyridanthrax spp. are not uniform. Here, we report that Th. fenestratus switches facultatively between killing the host almost immediately (idiobiont strategy) and killing the host at a later developmental stage (koinobiont strategy). We document the koinobiont parasitoid strategy for a series of Th. fenestratus larvae parasitizing P. fabricii. We found that a significant portion of Th. fenestratus larvae spend winter as young larvae and start feeding on fully developed and defecated prepupae of P. fabricii only after the end of cold-induced winter diapause. The time needed for the development of Th. fenestratus larvae exceeds several times the time needed for pupation of P. fabricii prepupae; the parasitized prepupae, therefore, remain paralyzed until the parasitic larva completes feeding. Fungicides, which alter the pupation of the host larva, seem to have negligible effects on Th. fenestratus larvae. The ability to switch between the two parasitism strategies has already been reported for several Anthrax spp., though the ability to block the host in the defecated prepupa stage and prevent its pupation following cold-induced diapause is herein reported for the first time.

Abstract Three Crabronid wasp species viz., Dasyproctus agilis (F. Smith, 1858), D. buddha (Cameron, 1899) and Crossocerus pusanus Leclercq, 1956 were recorded for the first time from the spice ecosystem.

Azole fungicides have been essential pillars of global food security since the commercialization of triadimefon. However, the potential for fungicides to induce sublethal effects on larval development and emergence from overwintering is underresearched. We hypothesized that contact exposure to field-realistic concentrations of a broad spectrum of triazole fungicides alters the pupation and metamorphosis of crabronid wasps. Therefore, triazole fungicides shape the hymenopteran communities in agrocenoses. We applied field-realistic concentrations of three triazole fungicides, difenoconazole, penconazole, and tebuconazole, to the defecated prepupae of Pemphredon fabricii (Hymenoptera: Crabronidae). We monitored their survival, pupation, and metamorphosis into adults, including the timing of these events. All three tested triazole fungicides altered the time to the metamorphosis into adults of P. fabricii prepupae compared to the vehicle-treated controls. This effect was concentration-independent within the recommended concentration ranges for foliar applications. However, the three triazole fungicides were not associated with any significant declines in overall survival. Thus, the commonly used triazole fungicides affect the synchronization of the metamorphosis into adults with the availability of food and nesting resources of the study species. The study compounds did not affect the survival, which agrees with previous studies of other azole fungicides, which revealed effects on survival only when used in combination with other compounds. Further research should address the multiplicative effects of the triazole fungicides with other agrochemicals on the timing of the metamorphosis of bees and wasps.

The first crabronid wasps (Hymenoptera, Apoidea) from the Crato Formation (Northeastern Brazil) and implications for the evolution of apoid wasps and bees during the Early Cretaceous

The crabronid wasp, Solierella turneri Dutt, 1917 (Hymenoptera: Crabronidae) is newly recorded from various regions of India and female is described. Hitherto, the S. turneri Dutt has been only reported from northern India (Pusa of Bihar), the current record extends its range to southern India (Kerala, Tamil Nadu and Karnataka).

Anthropogenic habitats that are contaminated by toxic elements were recently shown to host abundant and diverse assemblages of bees and wasps (Hymenoptera: Aculeata), including numerous threatened species. However, toxic elements adversely affect insect fitness. We address the effects of toxic elements on aculeate inquilines that occupy Lipara lucens-induced galls on the common reed, Phragmites australis. We hypothesized that contamination of potential nesting and feeding habitats is associated with adverse changes in bee and wasp populations that are attracted in these environments. To address this hypothesis, we analyzed the contents of As, Cd, Cu, Pb, Zn, Fe, and S in site-matched samples of soil, reed galls, and crabronid wasp bodies and correlated them with abundance and species richness of aculeate hymenopterans in reed galls and with the number of larvae in nests of the eudominant hymenopteran, Pemphredon fabricii. The common reed was present at all the examined sites, and L. lucens-induced galls were present at all but one sampling site; the single exception was the sampling site with the highest contents of four of the seven analyzed elements. The alpha diversity of gall-associated aculeate inquilines, abundance of P. fabricii, and number of prepupae per nest of P. fabricii were not correlated with the contents of any of the seven analyzed toxic elements. We found P. fabricii to be abundantly present in habitats with extreme concentrations of toxic elements. Exposed P. fabricii accumulated Cd, Cu, and Pb, while they eliminated Fe and Zn. The obtained data did not support the hypothesis that heavy metal contamination of anthropogenic sites affects P. fabricii and other reed gall-associated aculeates.

Trachypus Klug is a Neotropical genus of crabronid wasps comprising 31 ground-nesting species. Its species can be solitary or communal, and two diet ranges are known: they can forage on several bee subfamilies and wasps; or can be specialists on stingless bees. Natural history observations are scarce nowadays but are essential to contextualize ecological and evolutionary studies. Here we report new records and give biological notes for Trachypus elongatus (Fabricius, 1804), Trachypus taschenbergi Rubio-Espina, 1975, and Trachypus varius (Taschenberg, 1875). Observations and samplings were carried out twice a month, during one year in the city of Curitiba, southern Brazil. Besides field observations, circular statistics were used to analyze seasonality. All species nest in sloped soil and are solitary. Trachypus elongatus and T. taschenbergi were active during most of the year with marked seasonality in the late spring and early summer. Both species were observed hunting only stingless bees, with T. elongatus specialized on Trigona spinipes (Fabricius, 1793), and T. taschenbergi specialized on Paratrigona subnuda Moure, 1947 drones. Trachypus varius was observed only in January and one female was recorded foraging on a Paratrigona subnuda worker. Our observations provide additional data for understanding the biology of bee-hunting wasps, and this is the first study to bring information for T. taschenbergi and T. varius. Our data corroborate that some species of the genus Trachypus are specialized on stingless bees.

An updated checklist of the wasp family Crabronidae in Turkey is provided. It is based on records present in the literature and on newly identified specimens collected in Turkey. In this study, 537 species and 16 subspecies in 65 genera are listed. Among them, five species, namely Dryudella esterinae Pagliano, 2001, Nysson mimulus Valkeila, 1964, Crossocerus pullulus A. Morawitz, 1866, Oxybelus spectabilis Gerstaecker, 1867 and Diodontus insidiosus Spooner, 1938 are recorded for the first time from Turkey. New and additional records for 114 species are given. Collection localities and photographs of newly identified species are provided. Key words: Hymenoptera, Crabronidae, checklist, new records, additional records, Turkey

Abstract Two Indian Crabronid wasp species viz., Lestica quadriceps (Bingham, 1897) and Isorhopalum marunum Leclercq, 1963 were redescribed with additional characters of male genitalia along with coloured illustrations. New locality records are also included.

Oxybelus lusitanicus spec. nov., a new European Crabronid wasp species is described and diagnosed. It is currently known only from two regions of Portugal. An amendment to the relevant section of Guichard's (1993) most recent English language key to European Oxybelus Latreille, 1796 is included.

Neonicotinoid insecticides are associated with a decline in the diversity and distribution of bees and wasps (Hymenoptera: Aculeata). The effects of neonicotinoids on the metamorphosis of aculeates have never been addressed in detail; however, recent evidence suggests that neonicotinoids induce wing abnormalities. We hypothesized that the metamorphosis success of bees and wasps differs in response to contact exposure to field-realistic concentrations of neonicotinoid insecticides or in response to combined exposure to neonicotinoid insecticides and benzimidazole fungicides. We treated prepupae of the model crabronid wasp Pemphredon fabricii with field-realistic concentrations of four neonicotinoids, acetamiprid, imidacloprid, thiacloprid and thiamethoxam, and/or with the benzimidazole fungicide thiabendazole. Treatment with acetamiprid or imidacloprid decreased the pupation rates to only 39% and 32%, respectively. Treatment with thiacloprid or thiamethoxam did not affect the pupation rate when applied alone, but the subsequent treatment of thiacloprid- or thiamethoxam-treated prepupae with thiabendazole led to significant decreases in pupation rates. A high concentration of acetamiprid, which severely affected the pupation rates, had moderate effects on metamorphosis into adults, resulting in 53% metamorphosis success (as opposed to 95% metamorphosis success in the water-treated group). However, imidacloprid or thiamethoxam treatment resulted in only 5%-10% metamorphosis success into adults. Overall survival decreased in response to treatment with any of the neonicotinoids or benzimidazoles or their combinations, with extremely low survival (<2%) following combined treatment with imidacloprid and thiabendazole or thiamethoxam and thiabendazole. In conclusion, neonicotinoids alter insect metamorphosis success, which can be further potentiated by their combination with other agrochemicals, such as benzimidazoles.

Crabronid wasp Lindenius abditus Kohl, 1898 is recorded for the first time from Turkey. Recorded species are described and taxonomically important morphological characters are photographed.

Scent training and field detection trials were conducted to determine if honey bee (Apis mellifera) foraging behavior could be employed as a practical application in the location of vertebrate carrion. Resource recognition and querying trials consisted of two components. Honey bees were trained to associate chemical compounds found in decaying tissues with a high-quality food source via introduction of the compounds into a sugar solution. Randomized scented and non-scented sugar solution choices were subsequently provided to hived bees at varying distances within a rural outdoor study area. Following initial forager recruitment by scouts, twice the number of bees were observed feeding at carrion-scented stations. Additional field trials performed using wildlife carrion reinforced experimental results. Scent trained scout bees showed a marked interest in decomposing wildlife remains by aerially investigating and landing on the carrion. These findings demonstrate honey bee retention of carrion sensory recognition capabilities and support the crabronid wasp hypothesis of honey bee evolutionary origins. Applications for forensic remains detection, wildlife trafficking interdiction, and endangered species conservation are indicated.

Revised checklist of the genus Cerceris (Hymenoptera: Crabronidae) of Iran, with two new records

The effects of contact exposure to azole fungicides on insect metamorphosis

Until now the Crabronidae fauna of the Maltese Islands comprised 45 species in 5 subfamilies. Recently, one of us (EX) while studying insect visitors on flowers of Capparis orientalis found a new crabronid species from Malta, Spilomena mocsaryi Kohl, 1898. A check-list of the 46 species of Crabronidae so far recorded from the Maltese Islands is provided.

Parasitic Hymenoptera usually need to have direct access to their host or its offspring or to be able to enter and place their offspring in a nest of their host, where their progeny develop at the expense of the host. In the case of the cleptoparasitic cuckoo wasps (Chrysididae) their main target is the nest of the host and they have various strategies for locating and entering their host's brood cells for ovipositing. The chrysidid Omalus biaccinctus (Buysson, 1893), a parasitoid of aphid hunting crabronid wasps, was observed ap- parently inserting its eggs into living aphids at the hunting site of their host and the presence of the parasitoid's egg and DNA in aphids after oviposition was confirmed. It is concluded that O. biaccinctus hitch-hikes into a host's brood cell concealed in the aphid prey collected by the host wasp and the adult parasites do not need to enter the nest of their host in order to lay their eggs.