Dolichovespula Saxonica Research Articles

The genome sequence of the Saxon Wasp, Dolichovespula saxonica (Fabricius, 1793).

We present a genome assembly from an individual male Dolichovespula saxonica (the Saxon Wasp; Arthropoda; Insecta; Hymenoptera; Vespidae). The genome sequence is 221.8 megabases in span. Most of the assembly is scaffolded into 26 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 18.97 kilobases in length. Gene annotation of this assembly on Ensembl identified 10,856 protein coding genes.

Chemical signatures of egg maternity and Dufour’s gland in Vespine wasps

Cuticular hydrocarbons (CHCs) are often used in the chemical communication among social insects. CHCs can be used in nestmate recognition and as queen pheromones, the latter allows the regulation of the reproductive division of labor. In the common wasp Vespula vulgaris, CHCs and egg-marking hydrocarbons are caste-specific, being hydrocarbon queen pheromones and egg maternity signals. Whether these compounds are conserved among other Vespinae wasps remains unknown. Queens, virgin queens, reproductive workers, and workers belonging to four different wasp species, Dolichovespula media, Dolichovespula saxonica, Vespa crabro, and Vespula germanica, were collected and studied. The cuticular hydrocarbons, egg surface, and Dufour's gland composition were characterized and it was found that chemical compounds are caste-specific in the four species. Quantitative and qualitative differences were detected in the cuticle, eggs, and Dufour's gland. Some specific hydrocarbons that were shown to be overproduced in the cuticle of queens were also present in higher quantities in queen-laid eggs and in their Dufour's gland. These hydrocarbons can be indicated as putative fertility signals that regulate the division of reproductive labor in these Vespine societies. Our results are in line with the literature for V. vulgaris and D. saxonica, in which hydrocarbons were shown to be conserved queen signals. This work presents correlative evidence that queen chemical compounds are found not only over the body surface of females but also in other sources, such as the Dufour's gland and eggs.

All-day activity of Dolichovespula saxonica (Hymenoptera, Vespidae) colonies in Central Finland

In social vespid wasps, colony activity varies at many temporal scales. We studied the peak season activity (number of individuals entering the nest per min) of colonies of the social vespine wasp Dolichovespula saxonica in its native range in boreal Finland. Six colonies were monitored non-stop for a full day, starting before sunrise and ending after sunset. Shorter monitoring was carried out before and/or after the full-day monitoring. All colonies were active before sunrise and after sunset, and the overall activity was positively linked with colony size. Activity showed irregular minute-to-minute cycles in all colonies. The broader within-day dynamics were idiosyncratic among the colonies: activity varied generally between 40–100% of the peak, there were usually a few peaks per day, and the timing of the peaks varied. Ambient temperature was not related to activity dynamics consistently. Our study provides high-resolution information about the all-day activity of D. saxonica and underscores high among-colony variability in the dynamics of vespine wasps.

Different preferences for new versus old nestboxes by birds, rodents and social insects

The use of artificial nestboxes has improved the understanding of the ecology and behaviour of secondary cavity-nesting animals. Although earlier investigations have shown that nestbox characteristics can influence where animals roost or breed, the impact of ageing of nestboxes on occupation rates has rarely been investigated with experiments based on choice. In this study, the occupation rate of new and old wooden nestboxes set up side by side on the same tree (n = 140 pairs) was investigated in mixed coniferous-deciduous forest in Lithuania. Great tits Parus major and pied flycatchers Ficedula hypoleuca evidently preferred to breed in new nestboxes, while hazel dormice Muscardinus avellanarius and yellow-necked mice Apodemus flavicollis did not show any preference to a certain nestbox type and equally occupied old and new nestboxes. Saxon wasps Dolichovespula saxonica also occupied both nestbox types equally and a similar tendency was observed in European hornets Vespa crabro. By contrast, black garden ants Lasius niger showed a tendency to occupy old nestboxes. The results of the present study are important when considering the use of nestboxes in monitoring small hole-nesting birds and hazel dormice. The preference of birds for new nestboxes may influence long-term monitoring results when nestboxes become older and when old nestboxes are replaced with new ones. This important limitation has not been emphasised in review papers on the inadequacies of nestboxes in studies of hole-nesting birds. However, as ageing of nestboxes does not influence the occupation rates by hazel dormice, the use of nestboxes does not bias the results of long-term monitoring of this species.

The Nesting Ecology of Social Wasps (Hymenoptera: Vespidae: Vespinae and Polistinae) in Northern Mongolia

Observations on the nesting characteristics and colony life of Mongolian social wasps are essential to the field due to the peripheral locations of species distribution ranges and critical lack of such information. We found 35 nests of seven social wasp species, including three vespine species (Dolichovespula saxonica, D. media and Vespula vulgaris) and four polistine species (Polistes snelleni, P. riparius, P. nimpha and P. biglumis). Riparian woodland was the habitat where the most species (five out of seven) nests were found. Nests of P. snelleni, Baikal-Far Eastern species, were found only in river cut banks, in holes probably originally excavated by passerine birds most likely sand martin (Riparia riparia). Nesting sites of D. saxonica were the most diverse (bank hole, underground, aerial and birch stump/logs). Colony size of vespine wasps in northern Mongolia was relatively small (36-60 individuals). Nests of Polistes species (except P. snelleni) were found frequently on the branches of willow (Salix sp.) and wild rose (Rosa acicularis). Other characteristics associated with each species nest were considered separately.

Conservation of Queen Pheromones Across Two Species of Vespine Wasps.

Social insects are known for their reproductive division of labor between queens and workers, whereby queens lay the majority of the colony's eggs, and workers engage mostly in non-reproductive tasks. Queens produce pheromones that signal their presence and fertility to workers, which in turn generally remain sterile. Recently, it has been discovered that specific queen-characteristic cuticular hydrocarbons (CHCs) function as queen pheromones across multiple lineages of social insects. In the common wasp, Vespula vulgaris, several long-chain linear alkanes and 3-methylalkanes were shown to act as queen signals. Here, we describe similar bioassays with a related species of highly eusocial vespine wasp, the Saxon wasp, Dolichovespula saxonica. We show that a blend of queen-characteristic hydrocarbons that are structurally related to those of the common wasp inhibit worker reproduction, suggesting conservation of queen pheromones across social wasps. Overall, our results highlight the central importance of CHCs in chemical communication among social insects in general, and as conserved queen pheromones in these social wasps in particular.

Structure of Nests and Colony Sizes of the European Hornet (Vespa crabro) and Saxon wasp (Dolichovespula saxonica) (Hymenoptera: Vespinae) in Urban Conditions

Studies of different groups of insects in urban areas sometimes show large populations, greater than in non-urban areas. The reason for this is a presence in the cities some of dominating species which often occur almost en masse.This group includes, inter alia, hymenopterans and especially social wasps (Vespinae). Colonies and nests of two wasp species, the European hornet (Vespa crabro) and Saxon wasp (Dolichovespula saxonica) in areas of the city of Łódź in Poland were studied. Whole colonies positioned both in buildings as well in natural places, size of societies, parameters their nests, differentiation of cells in combs and their location were investigated. We also studied the correlation between the size of the nest and societies of these insects. It was found that nests established in the buildings are much larger, produced more individuals of reproductive castes and thus obtained a better reproductivesuccess especially for the hornet colonies whose queens prefer the buildings as a place to nest.

Phenology of European Hornet, Vespa crabro L. and Saxon Wasps, Dolichovespula saxonica Fabr. (Hymenoptera: Vespidae) and the Influence of the Weather on the Reproductive Success of Wasps Societies in Urban Conditions

In subsequent years, changes in the period of colonies activity for both species of wasps were observed as well as the longer period of development of wasp societies in the city than in the forest. There was not found a clear influence of weather conditions in winter on date of colonies initiation. However, low temperatures and rainfall in May caused delaying the initiation of nesting. The temperature in winter had a little impact on the number of queens that survived the winter and established their colonies in spring, but the humidity in winter had influence on the count of queens and thereby on the number of future nests especially in the forest area.

Factors restricting the abundance of wasp colonies of the European hornet <i>Vespa crabro</i> and the Saxon wasp <i>Dolichovespula saxonica</i> (Hymenoptera: Vespidae) in an urban area in Poland

Various factors affecting the reproductive success of Vespacrabro and Dolichovespula saxonica (Vespinae), including their parasitoids, parasites, pathogens and other micro organisms accompanying their nests in the city of LódzŸ in Poland were investigated. Sphecophaga vesparum, Aphomia sociella and especially Quedius brevicornis, whose larvae cause destruction of wasp nests, were recorded. Totally 19 species or groups of bacteria, including pathogens like Pseudomon aeruginosa, Enterobacter cloacae, Staphylococcus aureus and Enterococcus faecalis, and 5 species of fungi were identified. Cities create very good conditions for wasp societies. Unfortunately, their presence can cause specific but important risks to humans, which lead to massive destruction of wasp nests. However, this does not cause considerable decrease in the number of colonies of common wasp species but less abundant species may be endangered in cities by this practice. It is thus recommended to limit the number of all wasp nests destroyed and to discriminate between the species.

QUEEN SIGNALING IN SOCIAL WASPS

Social Hymenoptera are characterized by a reproductive division of labor, whereby queens perform most of the reproduction and workers help to raise her offspring. A long-lasting debate is whether queens maintain this reproductive dominance by manipulating their daughter workers into remaining sterile (queen control), or if instead queens honestly signal their fertility and workers reproduce according to their own evolutionary incentives (queen signaling). Here, we test these competing hypotheses using data from Vespine wasps. We show that in natural colonies of the Saxon wasp, Dolichovespula saxonica, queens emit reliable chemical cues of their true fertility and that these putative queen signals decrease as the colony develops and worker reproduction increases. Moreover, these putative pheromones of D. saxonica show significant conservation with those of Vespula vulgaris and other Vespinae, thereby arguing against fast evolution of signals as a result of a queen-worker arms race ensuing from queen control. Lastly, levels of worker reproduction in these species correspond well with their average colony kin structures, as predicted by the queen signaling hypothesis but not the queen control hypothesis. Altogether, this correlative yet comprehensive analysis provides compelling evidence that honest signaling explains levels of reproductive division of labor in social wasps.

Colony stage and not facultative policing explains pattern of worker reproduction in the Saxon wasp

Inclusive fitness theory predicts that in colonies of social Hymenoptera headed by a multiple-mated queen, workers should benefit from policing eggs laid by other workers. Foster & Ratnieks provided evidence that in the vespine wasp Dolichovespula saxonica, workers police other workers' eggs only in colonies headed by a multiple-mated queen, but not in those headed by a single-mated one. This conclusion, however, was based on a relatively small sample size, and the original study did not control for possible confounding variables such as the seasonal colony progression of the nests. Our aim, therefore, was to reinvestigate whether or not facultative worker policing occurs in D.saxonica. Remarkably, our data show that in the studied Danish population, there was no correlation between worker-worker relatedness and the percentage of worker-derived males. In addition, we show that variability in cuticular hydrocarbon profiles among the workers did not significantly correlate with relatedness and that workers therefore probably did not have sufficient information on queen mating frequency from the workers' cuticular hydrocarbon profiles. Hence, there was no evidence that workers facultatively policed other workers' eggs in response to queen mating frequency. Nevertheless, our data do show that the seasonal progression of the nest and the location in which the males were reared both explain the patterns of worker reproduction found. Overall, our results suggest that the earlier evidence for facultative worker policing in D.saxonica may have been caused by accidental correlations with certain confounding variables, or, alternatively, that there are large interpopulation differences in the expression of worker policing.

Nesting interactions of the social wasp Dolichovespula saxonica [F.] (Hymenoptera: Vespinae) in wooden nest boxes for birds in the forest reserve „Las Piwnicki” in the Chełmno Land (Northern Poland)

The aim of this research was to investigate the process of colonization in wooden nest boxes for birds by the wasp Dolichovespula saxonica [F.] in the forest reserve “Las Piwnicki” during 1986-1987. About 69% of 150 nest boxes were colonized (36% by D. saxonica) in 1986 and 35% (10% by D. saxonica) in 1987. Parasite Shecophaga vesparum Court was observed inside small cell nests (SC) and large cell nests (LC) in the ratio of 5(SC) : 3(LC). During the two seasons, the decrease in the number of parasited nests followed with the ratio of 10(1986) : 1(1987). Competition of the „wasp - wasp” type (VV) compared to other competition types, such as „wasp - bird” (VA) and different types with wasps (DT), was the most frequent one among the interactions and followed with the ratio 1(VV) : 7(VA) : 5(DT). The number and proportions of construction types of nests during the studied growing seasons seem to prove the regular and irregular development of the Dolichovespula saxonica colony.

A Comparative Study on the Pollination Mechanism of <I>Anisodus luridus</I> and <I>A. carniolicoides</I> (Solanaceae)

Empirical studies comparing mating systems and pollination mechanisms in closely related species within one genus will help us to better understand the evolution of plant mating system . In the present study , we performed field experiments on Anisodus luridus and A. carniolicoides , attempting to explore the evolution of self-compatibility and pollinator shift in the genus Anisodus . Our results showed that both A. luridus and A. carniolicoides were fully self-compatible , but the seed number and fruit set of the netted flowers without emasculation were significantly lower than the intact control flowers subjected to open pollination , indicating the two species only had a weak ability of autonomous selfing . Seed production with supplemental pollen was greatly enhanced compared with natural flowers , suggesting pollen limitation in both species . Vespula rufarufa and Dolichovespula saxonica . were the most frequent pollinators of A. luridus and A. carniolicoides , respectively . While other floral visitors , including bumblebees , flies and ants , accounted for the minority of visitation in the two species . The number of pollen grains deposited on stigmas of intact flowers within one day was significantly higher than emasculated flowers in A. carniolicoides , but not in A. luridus . Therefore , visitations of D . saxonica to A. carniolicoides 云 南 植 物 研 究 2009 , 31 (3) : 211~218 Acta Botanica Yunnanica DOI : 10 .3724�SP. J . 1143 .2009.08198

Vulgarogamasus sphecophilus (Cooreman) comb. nov. (Acari: Mesostigmata: Parasitidae): a redescription and new hymenopteran association

Eugamasus sphecophilus Cooreman is transferred to the genus Vulgarogamasus, redescribed (female, male and deutonymph), and proposed as a senior synonym of Poecilochirus britannicus Hyatt. The male and female deutonymph of the species are distinguished for the first time. Vulgarogamasus sphecophilus comb. nov. is recorded in association with the social wasp Dolichovespula saxonica for the first time, where it was observed causing significant egg mortality. As the result of the new synonymy, the geographical range of V. sphecophilus now includes the British Isles.

Influence of Illuminance and Forager Experience on Use of Orientation Cues in Social Wasps (Vespinae)

We tested the influence of illuminance and level of forager experience on nest orientation behavior of the social wasps Vespula vulgaris, Vespa crabro, and Dolichovespula saxonica in an artificial laboratory tunnel system. The number of wasps which oriented themselves chemically via a terrestrial trail or used visual orientation were determined at different illuminance levels for foragers which were naive or experienced with the tunnel system. In V. vulgaris and D. saxonica, mainly the young and naive foragers used the chemical trail for orientation in brightness. Experienced foragers used visual cues for nest orientation. In V. crabro, naive and experienced foragers followed the chemical trail in a similar intensity. In darkness, when visual orientation was limited, the relative importance of the chemical trail increased dramatically in all species and all experience classes.

DrawWing, a program for numerical description of insect wings

There is usually a pattern of veins on an insect wing. This pattern is species-specific and is used taxonomically. For example, the coordinates of some characteristic points on the wing are used to compare vein patterns. The characteristic points are often vein junctions or vein ends. A tool is presented that enables automatic identification of vein junctions. An image of an insect wing is used to determine the wing outline and veins. The vein skeleton is obtained using a thinning algorithm. Bezier splines are fitted to both the wing outline and the vein skeleton. The splines are saved in an encapsulated postscript file. Another output file in text format contains the coordinates of vein junctions. Both the program and its source code are available under GNU General Public License at [www.cyf-kr.edu.pl/~rotofils/drawwing.html]. The program presented in this paper automatically provides a numerical description of an insect wing. It converts an image of an insect wing to a list of coordinates of vein junctions, and a wing diagram that can be used as an illustration. Coordinates of the vein junctions extracted by the program from wing images were used successfully to discriminate between males of Dolichovespula sylvestris and Dolichovespula saxonica.

DrawWing, a program for numerical description of insect wings

There is usually a pattern of veins on an insect wing. This pattern is species-specific and is used taxonomically. For example, the coordinates of some characteristic points on the wing are used to compare vein patterns. The characteristic points are often vein junctions or vein ends. A tool is presented that enables automatic identification of vein junctions. An image of an insect wing is used to determine the wing outline and veins. The vein skeleton is obtained using a thinning algorithm. Bezier splines are fitted to both the wing outline and the vein skeleton. The splines are saved in an encapsulated postscript file. Another output file in text format contains the coordinates of vein junctions. Both the program and its source code are available under GNU General Public License at [www.cyf-kr.edu.pl/~rotofils/drawwing.html]. The program presented in this paper automatically provides a numerical description of an insect wing. It converts an image of an insect wing to a list of coordinates of vein junctions, and a wing diagram that can be used as an illustration. Coordinates of the vein junctions extracted by the program from wing images were used successfully to discriminate between males of Dolichovespula sylvestris and Dolichovespula saxonica.

Use of terrestrial chemical trails for nest orientation in an open nesting wasp, Dolichovespula saxonica F.

The long-cheeked wasp Dolichovespula saxonica typically constructs exposed nests which can be reached by flying. Usually foragers do not walk on substrates in the close vicinity of the nests as cavity breeding wasps do (Steinmetz et al., 2002). Unexpectedly, when forced to walk outside the nest instead of flying in an artificial tunnel system, D. saxonica foragers lay a terrestrial trail and use it for orientation in the nest area in our experiments. 41% of the foragers followed the trail in a direction they were not accustomed to. We suggest that the foragers have employed the same orientation cues normally used for orientation in the close vicinity of the nest when approaching a free-hanging nest by flying, for example nest odour. Nest odour substances may have been transferred to the substrate as a trail as a consequence of foragers walking through the tunnels.

Hymenoptera (Aculeata) of spruce stands in the air-pollution region of Northern Bohemia

Using Moericke’s yellow dishes we studied the Hymenoptera (Aculeata) fauna (with the exception of Formicoidea) in spruce (Picea abies) stands of the colder region of Northern Bohemia. We collected 103 species and the most important species in this spectrum were Vespula vulgaris (56.4%), Vespula rufa (4.7%), Dolichovespula norvegica (3.1%), Dolichovespula saxonica (4%), Nysson spinosus (1.8%), Andrena lappona (1.9%), Cleptes semiauratus (5.9%), Halictus sp. (6.7%) and Trypoxylon minus (2.2%). Comparisons made in 1990–1994 and 1995–1999 indicated a recession of species of the genus Halictus, of Andrena nitida (Apidae), Pemphredon lugubris, Trypoxylon clavicerum and T. minus (Sphecidae), and an increased abundance of Cleptes semiauratus (Cleptidae), Nysson spinosus (Sphecidae), Vespula vulgaris and V. rufa (Vespidae). Compared to closed stands, open spruce stands had a greater species diversity and lower number of captured specimens.

Paternity, reproduction and conflict in vespine wasps: a model system for testing kin selection predictions

The Vespinae wasps (Vespa, Provespa, Dolichovespula, and Vespula) are an excellent group for testing kin selection predictions. There is considerable variation in kin structure and conflict resolution in a group of known phylogeny where all species have a similar basic biology: morphologically distinct queens and workers, and annual nests headed by a single queen. Vespine kin structure can be described by a single variable "effective paternity", which is defined by queen mating frequency and sperm use. Low effective paternity, which causes high worker relatedness, is basal in the group (Vespa, Dolichovespula), with high paternity (ca >2) restricted to Vespula whose queens mate more and use sperm more equally. Paternity variation correlates well with observed patterns of reproduction and conflict. As predicted by theory, male production by workers is common in Dolichovespula but not in Vespula where worker policing occurs (Vespula vulgaris). The theory is also supported by intercolony variation in Dolichovespula, with facultative worker policing (Dolichovespula saxonica) and sex allocation biasing by workers (D. arenaria) occurring in response to paternity. In addition, queen loss in reproductive colonies of nine species is negatively correlated with paternity, in line with the prediction that matricide is only expected at low paternity. However, paternity does not explain the reproductive characteristics of Vespa crabro. Although paternity in V. crabro is only 1.1, the same as the mean in six Dolichovespula species, its reproductive behaviour is different from Dolichovespula. More like Vespula, V. crabro has worker policing, workers that rarely have active ovaries, and little queen loss in reproductive-phase colonies.