Species Of Digger Wasps Research Articles

Communities of Digger Wasps (Hymenoptera: Spheciformes) along a Tree Cover Gradient in the Cultural Landscape of River Valleys in Poland.

This study of digger wasps (Hymenoptera: Spheciformes) was carried out in the cultural landscape of the Drwęca, Lower Vistula, and Warta river valleys in northern Poland during 2011-2013. The study was undertaken on sites representing a succession gradient from dry grasslands to high levels of tree cover which we hypothesised would influence the structure of digger wasp communities. During our research additional information on flower use, insect prey, and phenology was also recorded and is reported here, revealing dependencies between woodland cover and both the prey and nesting types of digger wasps. A total of 136 species were recorded, i.e., nearly 56% of all Spheciformes species recorded from Poland. Among the species collected, 30 were on the Red List of Threatened Animals in Poland. Most endangered species were recorded in psammophilous grasslands, which are open habitats, and the least in mesic sites. These results significantly update the known distribution of the digger wasp in northern Poland. Knowledge on the biology of digger wasps in Poland is also supplemented by information on the feeding of larvae of 14 species and information on food plants visited by imago digger wasps. The results of our research confirm the correlations between the increase in forest cover and the number of digger wasp species.

Two new species of Astata Latreille from Iran (Hymenoptera, Astatidae)

Two new digger wasp species of the genus Astata Latreille, 1796 (Hymenoptera, Astatidae), A. ljubomirovi sp. nov. and A. rubriventris sp. nov. are described from Iran. Moreover, A. compta Nurse is newly recorded from the Palaearctic region and Iran, redescribed and illustrated. Diagnostic characters and key features to each species are given. With the present additions, the total number of Astata recorded from Iran increases up to 14.

New and little-known digger wasps (Hymenoptera: Ampulicidae, Sphecidae, Crabronidae) from Russia.

New additions to the knowledge of digger wasps (Ampulicidae, Sphecidae, Crabronidae) in Russia are provided. Tachysphex loktionovi Mokrousov Proshchalykin, sp. nov. is described from Tyva Republic. Five species of digger wasps are reported from Russia for the first time: Hoplammophila clypeata (Mocsáry, 1883) (Sphecidae), Tachysphex desertorum F. Morawitz, 1894, T. mongolicus Kohl, 1898, Tachytes argenteus Gussakovskij, 1933, and Trypoxylon albipes F. Smith, 1856 (Crabronidae). Misidentified Tachysphex speciosissimus Morice, 1897 (=T. gussakovskii Pulawski, 1971) is excluded from the fauna of Russia. Hitherto unknown male of Tachysphex mongolicus Kohl, 1898, stat. resurr. is described and regarded as a valid taxon. New synonymy is proposed for T. mongolicus Kohl, 1898 = T. abditus Kohl, 1898, syn. nov. Diagnosis for male of Dolichurus haemorrhous A. Costa, 1886 is updated. New regional records for seven species are recorded. The known fauna of Russia currently numbers three families, 87 genera and 694 species of digger wasps. In addition Tachytes argenteus Gussakovskij, 1933 is reported for the first time from Uzbekistan and Cyprus, and Trypoxylon beaumonti Antropov, 1991 is newly recorded from Ukraine.

Low Host Specialization in the Cuckoo Wasp, Parnopes grandior, Weakens Chemical Mimicry but Does Not Lead to Local Adaption.

Insect brood parasites have evolved a variety of strategies to avoid being detected by their hosts. Few previous studies on cuckoo wasps (Hymenoptera: Chrysididae), which are natural enemies of solitary wasps and bees, have shown that chemical mimicry, i.e., the biosynthesis of cuticular hydrocarbons (CHC) that match the host profile, evolved in several species. However, mimicry was not detected in all investigated host-parasite pairs. The effect of host range as a second factor that may play a role in evolution of mimicry has been neglected, since all previous studies were carried out on host specialists and at nesting sites where only one host species occurred. Here we studied the cuckoo wasp Parnopes grandior, which attacks many digger wasp species of the genus Bembix (Hymenoptera: Crabronidae). Given its weak host specialization, P. grandior may either locally adapt by increasing mimicry precision to only one of the sympatric hosts or it may evolve chemical insignificance by reducing the CHC profile complexity and/or CHCs amounts. At a study site harbouring three host species, we found evidence for a weak but appreciable chemical deception strategy in P. grandior. Indeed, the CHC profile of P. grandior was more similar to all sympatric Bembix species than to a non-host wasp species belonging to the same tribe as Bembix. Furthermore, P. grandior CHC profile was equally distant to all the hosts’ CHC profiles, thus not pointing towards local adaptation of the CHC profile to one of the hosts’ profile. We conducted behavioural assays suggesting that such weak mimicry is sufficient to reduce host aggression, even in absence of an insignificance strategy, which was not detected. Hence, we finally concluded that host range may indeed play a role in shaping the level of chemical mimicry in cuckoo wasps.

Functional morphology of the sting in two digger wasps (Hymenoptera: Crabronidae) with different types of prey transport

Digger wasps of the family Crabronidae (Insecta: Hymenoptera) are generally known to use their sting to paralyze or kill a prey. However, only a few species of digger wasps transport their prey to the nest impaled on the sting. How sting morphology correlates with this peculiar type of prey carriage is still unclear. We examined the sting morphology of two phylogenetically closely-related species of digger wasps of similar size, which hunt for similar preys but use different types of prey transportation. Data from light microscopy (LM), scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were analyzed to find possible correlations between shape, material composition, and function of the stings. The similarity of the material composition in the stings of the two species suggests that the material of stings does not play a dominant role in their functional differences. On the contrary, differences in the curvature and surface sculpture of sting elements likely result in different stress distributions under mechanical loading.

New data on the distribution of digger wasps of the genus Ammophila W. Kirby, 1798 (Hymenoptera, Sphecidae)

An annotated list is given and the distribution of five species of digger wasps genus Ammophila, collected in the circumpolar regions of Western Siberia (in the Yamalo-Nenets Autonomous District) in 2017, is specified.

Egg-laying behavior and morphological and chemical characterization of egg surface and egg attachment glue of the digger wasp Ampulex compressa (Hymenoptera, Ampulicidae)

For providing their offspring females of the digger wasp species Ampulex compressa hunt cockroaches, paralyze them and attach as a rule one egg to the coxa of one of the mid legs of their prey. We observed the egg-laying behavior and examined with light- and scanning microscopy (i) nearly mature eggs from ovaries of freshly dissected females and (ii) eggs immediately after their deposition on the coxae of their prey. The length of the white bean-shaped eggs varied between 2.2 and 3.0 mm, their diameter between 0.66 and 0.72 mm, and their weight between 345 and 832 μg. The surface of fresh, untreated eggs shows even at higher magnifications (>20.000×) a smooth appearance. However, after conventional fixation, dehydration with ethyl-alcohol and critical-point drying the egg-surface exhibited a little bit texture. The eggs are at two-third of their underside glued to the coxa of the prey. With the naked eye the glue appears as a compact mass. The eggs may be mechanically removed from the substrate (their attachment site); however, in doing so the viscous attachment glue appears in a more fibrous consistence. The polypeptide composition washed off the egg surface and the glue revealed no similarities, whereas the molecular mass of two polypeptides were similar between glue and the Dufour's gland contents.

Can soda ash dumping grounds provide replacement habitats for digger wasps (Hymenoptera, Apoidea, Spheciformes)?

BackgroundPublished sources document a loss of biodiversity at an extreme rate, mainly because natural and semi-natural ecosystems are becoming fragmented and isolated, thus losing their biological functions. These changes significantly influence biological diversity, which is a complex phenomenon that changes over time. Contemporary ecologists must therefore draw attention to anthropogenic replacement habitats and increase their conservation status. In our studies we show the positive role of soda ash dumping grounds as an alternative habitat for digger wasps, especially the thermophilic species.Methodology/Principal findingsIn the years 2007–2010 we carried out investigations in postindustrial soda ash dumping grounds located in Central Poland. We demonstrated that these areas serve as replacement habitats for thermophilic species of Spheciformes and, indirectly, for their potential prey. The studies were conducted in three microhabitat types, varying in soil moisture, salinity and alkalinity, that were changing in the course of ecological succession. We trapped 2571 specimens belonging to 64 species of digger wasps. Species typical of open sunny spaces comprised 73% of the whole inventory. The obtained results suggest that the stage of succession determines the richness, abundance and diversity of Spheciformes. The most favorable conditions for digger wasps were observed in habitats at late successional stages.Conclusions/SignificanceOur results clearly showed that these habitats were replacement habitats for thermophilous Spheciformes, including rare taxa that require genetic, species and ecosystem protection, according to the Biodiversity Convention. We showed that some types of industry might play a positive role in the preservation of taxa in the landscape, and that even degraded industrial wasteland can replace habitats under anthropopressure, serving as refugia of biological diversity, especially for disturbance-dependent species.

Digger wasps (Hymenoptera, Apoidea: Ampulicidae, Sphecidae, Crabronidae) of the Black Sea coast of Krasnodar Territory, Abkhazia, and adjacent areas

A list of 208 digger-wasp species (Hymenoptera, Apoidea: Ampulicidae, Sphecidae, Crabronidae) from the Black Sea coast and adjacent areas within Krasnodar Territory, Abkhazia, and Adygea is given. Gorytes schmiedeknechti Handlirsch, 1888, Miscophus albufeirae Andrade, 1952, Psenulus fulvicornis (Schenck, 1857), and Passaloecus pictus Ribaut, 1952) are new to the Russian fauna, and 47 species are recorded for the first time from Abkhazia. Ectemnius guttatus (Vander Linden, 1829) does not occur in the Western Caucasus; the record of the species from this region was based on a misidentified female of E. lituratus Pz. Tachysphex gibbus Kohl, 1885, stat. n. is considered a distinct species based on its ecological and morphological features.

Venom and Dufour's glands of the emerald cockroach wasp Ampulex compressa (Insecta, Hymenoptera, Sphecidae): Structural and biochemical aspects

The digger wasp species Ampulex compressa produces its venom in two branched gland tubules. They terminate in a short common duct, which is bifurcated at its proximal end. One leg is linked with the venom reservoir, the other one extends to the ductus venatus. Each venom gland tubule possesses, over its entire length, a cuticle-lined central duct. Around this duct densely packed class 3 gland units each composed of a secretory cell and a canal cell are arranged. The position of their nuclei was demonstrated by DAPI staining. The brush border of the secretory cells surrounds the coiled end-apparatus. Venom is stored in a bladder like reservoir, which is surrounded by a thin reticulated layer of muscle fibres. The reservoir as a whole is lined with class 3 gland units. The tubiform Dufour's gland has a length of about 350 μm (∅ 125 μm) only and is surrounded by a network of pronounced striated muscle fibres. The glandular epithelium is mono-layered belonging to the class 1 type of insect epidermal glands. The gland cells are characterized by conspicuous lipid vesicles. Secretion of material via the gland cuticle into the gland lumen is apparent. Analysis of the polypeptide composition demonstrated that the free gland tubules and the venom reservoir contain numerous proteins ranging from 3.4 to 200 kDa. The polypeptide composition of the Dufour's gland is completely different and contains no lectin-binding glycoproteins, whereas a dominant component of the venom droplets is a glycoprotein of about 80 kDa. Comparison of the venom reservoir contents with the polypeptide pattern of venom droplets revealed that all of the major proteinaceous constituents are secreted. The secreted venom contains exclusively proteins present in the soluble contents of the venom gland. The most abundant compound class in the Dufour's gland consisted of n-alkanes followed by monomethyl-branched alkanes and alkadienes. Heptacosane was the most abundant n-alkane. Furthermore, a single volatile compound, 2-methylpentan-3-one, was identified in various concentrations in the lipid extract of the Dufour's gland.

New records of two alien mud daubers Sceliphron destillatorium (Ill.) and Sceliphron curvatum (Sm.) (Hymenoptera, Sphecidae) from Poland with comments on expansion of their ranges

The paper presents information on two species of digger wasps, Sceliphron destillatorium (Illiger, 1807) and S. curvatum (Smith, 1870), alien for the fauna of Poland (within its present borders). Both species are presently spreading in the country. Sceliphron destillatorium, a South-Palaearctic species, has been observed in Poland since 1960. Sceliphron curvatum was introduced to Europe from Asia in the 1970s, and at present it is known from many South- and Central-European countries. The species was found for the first time in Poland in 2003. New localities of the two species in Poland are given and issues connected with their present distribution are discussed.

Morphological distance and inter‐nest distance account for intra‐specific prey overlap in digger wasps (Hymenoptera: Crabronidae)

AbstractAlthough inter‐individual diet variation is common in predatory wasp populations, the factors accounting for such variation are still largely unknown. Here, we asked if paired diet dissimilarity in three species of digger wasps correlates with morphological distance and inter‐nest distance, two factors previously linked to diet partitioning in vertebrates. Results sharply differed among species and generations. All sampled populations showed significant inter‐individual diet variation for prey taxa, but only in half of the cases for prey size. In one generation of two species [Bembix zonata Klug and Stizus continuus (Klug)], similar‐sized wasps had similar prey taxonomic spectra (and for S. continuus also similar prey size spectra), a phenomenon which probably reduces intra‐specific competition. In addition, B. zonata females nesting closer to each other had more similar prey taxonomic spectra, suggesting that distant females probably hunt on different patches that harbour different prey species. For the females of a further species (Bembix merceti Parker), pairwise size difference and inter‐nest distance did not affect prey dissimilarity. Both morphological distance and inter‐nest distance are potentially important in shaping the overlap of individual resource use in wasps, though probably only in certain conditions such as a highly clumped distribution of nests and size‐related constraints on prey selection.

Nesting habitat segregation between closely related terricolous sphecid species (Hymenoptera:Spheciformes): key role of soil physical characteristics

Microhabitat selection based on abiotic factors was examined in five species of digger wasps (Sphex funerarius, Ammophila heydeni, Ammophila pubescens, Ammophila sabulosa, Bembix tarsata), four of which are of high conservation interest. All the study sites were located in areas affected by anthropogenic disturbance (reclaimed brown-coal mining areas, and railway dykes) in Central Europe. The individual species responded differentially to the variability in each of the physical characteristics measured, which resulted in site-specific exclusion of individual sphecid species. The sphecids were found to discriminate between available microhabitats based on ground inclination (slope) and vegetation cover. All but A. heydeni segregated the microhabitats according to the content of gravel and sand particles. S. funerarius and B. tarsata were limited by their preferences of low soil compactness, whereas A. pubescens utilized highly compacted soils, which were predominant in the study area. Soil shear strength (cohesiveness) was driving the level of gregariousness of the sphecids. In B. tarsata, number of cells per burrow was found to be higher in soils with increased penetration resistance. Experimental increase in soil compactness led to the abandonment of nesting microhabitats in the subsequent nesting seasons. Besides the well-known biotic factors, such as specialization at different size or type of prey, variability in abiotic factors between individual microhabitats (e.g. patches of sand) was found to be both necessary and sufficient to allow the parallel presence of viable populations of several sphecid species.

Sceliphron curvatum (F. Smith, 1870), a new in the fauna of Russia and invasive species of digger wasps (Hymenoptera: Sphecidae)

Sceliphron curvatum (F. Smith, 1870), a new in the fauna of Russia and invasive species of digger wasps (Hymenoptera: Sphecidae)

Digger wasp fauna (Insecta, Hymenoptera, Sphecidae, Crabronidae) of La Palma (Canary Islands) - a survey with description of a new species

Asurvey of the digger wasp fauna of La Palma (Canary Islands) is made. Eleven species are confirmed as present and five of them – Liris nigricans nigricans (Walker, 1871), Miscophus eatoni E. Saunders, 1903, Tachysphex nitidus (Spinola, 1806), Solierella insidiosa de Beaumont, 1964, and Nitela laevigata sp. n. – are recorded for the first time for the fauna of La Palma. A brief evaluation of the digger wasp species richness of La Palma is provided.

A new species of digger wasps of the genus Belomicroides (Hymenoptera, Crabronidae, Oxybelini) from North Africa

The new species of digger wasps, Belomicroides rufus, is described from North Africa. The new species differs from the all members of the Belomicroides schmiedeknechtii species-group in the pale coloration and dense pubescence of the body.

On the taxonomy of South African digger wasps of the tribe Oxybelini (Hymenoptera, Crabronidae)

Three South African species of digger wasps of the tribe Oxybelini, initially described in the genus Belomicrus A. Costa, B. (Nototis) bicornutus Arnold, B. (Nototis) crassus Arnold, and B. ferrieri Kohl, are considered to be members of the separate genera Nototis Arnold, 1927, Belarnoldus gen. n., and Belokohlus gen. n., respectively. The new species Nototis falcidens and the previously unknown male of N. bicornutus and female of B. crassus are described. The lectotype of B. ferrieri is designated.

Dufour gland of the digger wasp Liris niger: structure and developmental and biochemical aspects.

The tubiform Dufour gland in the digger wasp species Liris niger is about 1.0 mm long ( 0.15 mm). An alternating arrangement of longitudinal and circumferential bundles of striated muscle fibers surrounds the gland. The Dufour gland, together with the venom gland, enters the sting base and terminates in the sting. The glandular epithelium is monolayered. Glands about 3 day after imaginal ecdysis have an empty lumen but a thick lining epithelium. The gland cells are characterized by a well-developed vesicular smooth endoplasmic reticulum, sparse rough ER and numerous free ribosomes. They also exhibit several electron-lucent vesicles and autophagic vacuoles. Secretion of electron-dense material via the gland cuticle into the gland lumen is apparent. Glands more than 20 days after imaginal ecdysis display a large lumen and a thin epithelium. The cells show signs of degeneration with numerous cytolytic inclusions. Dufour gland liquid contains numerous polypeptides of molecular weights ranging from 14 to about 200 kDa. In addition the secretion consists predominantly of straight-chain hydrocarbons, accompanied by small amounts of esters. The major hydrocarbons are pentadecane and ( Z)-8-heptadecene. Dufour gland secretion may have several functions: (1). the polypeptides might be involved in the gluing process of the eggs, while (2). the hydrocarbon oils may function as lubricants for the lancets and (3). might soften the secretion, thus allowing easier application of the glue. The lipophilic volatile material (4). might also be involved in pheromonal signaling.

Digger wasp versus cricket: Mechanisms underlying the total paralysis caused by the predator's venom

The data presented here describe neurophysiological experiments addressing the question of cellular mechanisms underlying the total paralysis of locomotor behavior in crickets occurring after being stung by females of the digger wasp species Liris niger. The Liris venom effects have been studied by both in vivo recordings from identified neurons of the well-described giant fiber pathway and in vitro recordings from cultured neurons isolated from the terminal ganglion of crickets. The total paralysis of the prey is characterized by a general block of action potential generation as well as by a block of synaptic transmission. Intracellular recordings from neurons in intact ganglia under single electrode voltage-clamp conditions, as well as whole-cell patch-clamp recordings from cultured cricket neurons consistently show that the block of action potential generation by the Liris venom is due to a block of voltage-gated sodium inward currents in neurons of the stung ganglia. Furthermore, our data provide evidence that the Liris venom also blocks calcium currents in identified neurosecretory neurons. On the other hand, outward currents are not affected by the Liris venom. The in vitro recordings suggest that the Liris venom contains active venom components, which, at least for the observed block of inward currents, do not require a metabolic modification. Because venom application does not affect the ACh-induced EPSPs in giant interneurons, the Liris venom does not seem to influence the postsynaptic ACh receptors. The possible pre- and postsynaptic sites of venom action and the functional consequences on synaptic transmission within the giant fiber system are discussed.

Venom gland of the digger wasp Liris niger: morphology, ultrastructure, age-related changes and biochemical aspects.

Females of the parasitoid digger wasp species Liris niger hunt crickets as food for their future brood. The wasps paralyse the prey by injecting their venom directly into the CNS. The venom is produced in a gland consisting of two ramified glandular tubules terminating in a common reservoir. The reservoir contents enter the sting bulb via a ductus venatus. Secretory units of dermal gland type III line the two free gland tubules, the afferent ducts to the reservoir and the cap region within the reservoir. Secretion products of tubules reach the reservoir through the cuticle-lined central funnel. Secretory cells in the distal and middle parts of the tubules contain extensive rough endoplasmic reticulum and numerous electron-dense vesicles, whereas secretory cells of the afferent ducts and the cap region of the reservoir lack electron-dense vesicles and the endoplasmic reticulum is poorly developed. The secretory apparatus undergoes age-related changes. The secretory units in the venom gland tubules and inside the reservoir complete differentiation 1 day after imaginal ecdysis. After 30 days, massive autolytic processes occur in the secretory cells and in the epithelial cells of the reservoir. Analysis of the polypeptide composition demonstrates that the venom reservoir contains numerous proteins ranging from 3.4 to 200 kDa. A dominant component is a glycoprotein of about 90 kDa. In contrast the polypeptide composition of Dufour's gland is completely different and contains no glycoproteins. Comparison of the venom reservoir contents with the polypeptide pattern of venom droplets reveals that all of the major proteinaceous constituents become secreted. Thus the secreted venom contains exclusively proteins present in the soluble contents of the venom gland.