Nesting ecology of the wasp Sceliphron destillatorium (Illiger, 1807) (Hymenoptera,Sphecidae) in the Crimea

The nests of Sceliphron destillatorium in the Crimea were mainly built in attic spaces of houses and in various uninhabited buildings, and consisted of 3–39 (on average 16.5) cells. Twelve species of spiders from 11 genera of 4 families with predomination of Araneidae and Oxyopidae were recorded as prey. One nest cell contained 4–13 (on average 7.9) spiders, mostly adult ones. Successful development of S. destillatorium progeny was recorded in 48.6% of the cells; 26.5% of the progeny died from parasites: Amobia pelopei (16.0%), Chrysis taczanovskyi (4.3%), and Melittobia acasta (6.2%); 24.9% of the progeny died for unknown causes at the egg (13.0%) or prepupal (11.9%) stage. Nests of 17 other wasp and bee species from the families Pompilidae (2 species), Vespidae (4), Colletidae (1), and Megachilidae (10 species) were found in abandoned nest cells of S. destillatorium. The abundance of S. destillatorium has noticeably decreased in the last ten years, possibly due to immigration of a congener, S. curvatum, which has more diverse trophic links and a significantly higher rate of nesting success.     

Nesting behavior of Podium denticulatum Smith (Hymenoptera: Sphecidae)

The nesting behavior of Podium denticulatum Smith was studied on the campus of Ribeir?o Preto of the Universidade de S?o Paulo, SP, Brazil, from September 2003 to August 2005. The wasps established their nests in bamboo canes ranging from 11.4 cm to 26.2 cm in length and from 0.7 cm to 1.8 cm in internal diameter. Podium denticulatum nested almost exclusively in the hot and wet season (September-April), producing at least five generations per year. The cell provisioning was made with adult and nymphal cockroaches (Blattellidae) which were arranged venter-up and with the head inward toward the inner end of the cell. The construction of a temporary closure occurred in cells that took more than one day to be provisioned. The cells provisioned with a greater number of prey were more likely to produce females than males. The nests included 1-6 brood cells separated by mud partitions and arranged in a linear series. The innermost cells of the nests produced females, and the outermost cells produced males. Nests were parasitized by Eulophidae (Melittobia sp.), Chrysididae and Tachinidae.     

A population study in Jamaica on adult Sceliphron assimile (Dahlbom) (Hymenoptera: Sphecidae)

Abstract.

• 1 A mark–recapture study on the sphecid wasp Sceliphron assimile (Dahlbohm), analysed by Jolly's stochastic method (1965), was made from 3 December 1974 to 22 February 1975 at Green Bay, St Catherine, Jamaica.
• 2 Population levels in an 18.2 ha study area fluctuated about a mean of 281 for males, 259 for total females and 87 for reproducing females, while the probable carrying-capacity for these reproductives was about 104.
• 3 Mean estimated daily survival rates were 0.903 for males, 0.924 for total females and 0.945 for reproducing females. For the first two categories these rates decreased (p < 0.02) during the study, probably reflecting increasing emigration. Reproducing females probably do not emigrate and their survival did not significantly decrease.
• 4 Minimum age was linearly related to wing wear (r=+0.69, P < 0.001) and the latter associated with the progressive maturation and ageing of the ovaries. All surviving females become parous by middle age.
• 5 The mean rate of fecundity in the field was dependent on female age and was reduced during prolonged drought. Curves of total achieved fecundity appropriate to realistic survival rates give 4.2–16.8 eggs/female. The Jamaican mean was 9.6 ± 2.3 and that for Green Bay 8.6.
• 6 The proportion of females in the Green Bay population was 0.48 ± 0.03 while 0.55 was expected at emergence.
• 7 A cyclic budget is used to estimate immigration and emigration, and these were important causes of population change.
• 8 For Jamaica, only an estimated 28% of females survived to nest.

     

Life strategy and mortality factors of Sceliphron laetum (Smith) (Hymenoptera: Sphecidae) in Australia

Mortality factors and life-history strategy central to the population dynamics of a common Australian mud-daubing wasp Sceliphron laetum have been determined by the examination of remains left behind in mud nests. A life table has been constructed for the species and details of its life cycle, parasites and predators are presented. Results suggest that the effort involved in nest construction is rewarded by a very low egg, larval and pupal mortality, and that the population size may be limited by a shortage of suitable nesting sites.     

Nearnest behavior of a solitary muddaubing wasp,Sceliphron caementarium (Hymenoptera: Sphecidae)

Mud dauber wasps (Sceliphronspp.)construct nests by sequential flights to gather mud and return it to their aerial nests. Individual S. caementariumdiffer in the mean time spent in four states of construction: approach, daubing, inspection, and departure. Placing a novel object near nests or replacing a white object by a black one resulted in an increase in individuals' approach times but no change in departure times. Removal of objects or replacing a black object by a white one had no effect. A change in the color of objects near nests elicited increased approach times but did not affect departure. S. caementariumappears to memorize three-dimensional objects in the nearnest environment, and changes in the nearnest environment are learned during the approach flight to the nest. The frequency of significant responses to all manipulations decreased with successive visits by the wasps, suggesting habituation to nearnest changes.     

Orientation flights of solitary wasps (Cerceris; Sphecidae; Hymenoptera)

Bees and wasps are known to use a visual representation of the nest environment to guide the final approach to their nest. It is also known that they acquire this representation during an orientation flight performed on departure.A detailed film analysis shows that orientation flights in solitary wasps of the genus Cerceris consist of a systematic behavioural sequence: after lift-off from the nest entrance, wasps fly in ever increasing arcs around the nest. They fly along these arcs obliquely to their long axis and turn so that the nest entrance is held in the left or right visual field at retinal positions between 30° and 70° from the midline. Horizontal distance from the nest and height above ground increase throughout an orientation flight so that the nest is kept at retinal elevations between 45° and 60° below the horizon. The wasps' rate of turning is constant at between 100°/s and 200°/s independent of their distance from the nest and their ground velocity increases with distance. The consequence of this is that throughout the flight wasps circle at a constant angular velocity around the nest.Orientation flights are strongly influenced by landmark lay-out. Wasps adjust their flight-path and their orientation in a way that allows them to fixate the nest entrance and to hold the closest landmark in their frontal visual field.The orientation flight generates a specific topography of motion parallax across the visual field. This could be used by wasps to acquire a series of snapshots that all contain the nest position, to acquire snapshots of close landmarks only (distance filtering), to exclude shadow contours from their visual representation (figure-ground discrimination) or to gain information on the distance of landmarks relative to the nest.     

Further evidence of the Asian mud-daubing wasps in Europe (Hymenoptera: Sphecidae)

We report the further south‐eastward range extension of the invasive Asian mud‐daubing wasp, Sceliphron curvatum (Smith), initially introduced into Austria in the late 1970s. We document its presence in the central Balkan Peninsula from 1997 onwards, and we discuss the circumstances and course of its recent expansion in the area. We also report the first finding of another Asian species, Sceliphron deforme (Smith), in Europe, and we consider various aspects of this case, given the possibility that the record from southern Montenegro represents a successful introduction.     

The natural history of the mud-dauber wasp Sceliphron fistularium (Hymenoptera: Sphecidae) in southeastern Brazil

Nests of Sceliphron fistularium were obtained in Colombia and Moji Gua?u, S?o Paulo, Brazil. Complete nests consisted of 1 to 54 sausage-shaped cells, arranged side by side along a horizontal axis, and found attached to electrical wires (Colombia, n = 7) and walls (Colombia, n = 4 and Moji Gua?u, n = 4). The number of cells per nest ranged from 1 to 54, their length varying from 20.8 to 29.7 mm, and their diameter from 7.6 to 11.7 mm. Brood cells were provisioned with spiders of the family Araneidae. Only Alpaida veniliae was collected in Colombia, whereas the most frequent species found in Moji Gua?u was Micrathena swainsoni (62.0%) followed by M. acuta (23.3%). Adults emerged from June to October. The length and diameter of female and male cells were similar. Nevertheless, females were significantly larger than males. The sex ratio of individuals obtained from nests was 1.16 females: 1 male. A life table was constructed, and details of the life cycle of the wasps and parasitoids are presented. The most common mortality factors were either unknown or due to the parasitoid wasp Melittobia sp.     

Weight, volume and unbalancing: loading constraints of mud dauber wasps carrying mud balls

Load-carrying capacities of flying animals have important effects on their reproductive success, because it is expected that better performing individuals will benefit during activities such as foraging and nest building. Individually marking Sceliphron mud dauber wasp females and collecting their mud balls at three field sites, we investigated whether wasps maximize mud ball lifting and we evaluated whether the characteristics of soil affect wasp–mud ball size relationships. Sceliphron destillatorium , larger than Sceliphron spirifex , collected on average heavier and larger mud balls, and individual female body mass was positively correlated with the mass and volume of carried mud balls. Rarely mud balls reached a weight close to the theoretical maximum. On the other hand, the volume of mud balls roughly coincided on average with the theoretical maximum. A simple theoretical model showed that loss of balance during loaded flights is in part responsible for the failure to maximize the mass lifted, reducing the load-carrying capacity with a per cent value that is independent of the wasp's size. Soil characteristics also seem to affect the lifting dynamics of wasps: similar-size females carried significantly lighter mud balls in denser-soil sites. Our results showed that the volume is the strongest factor limiting mud ball carrying. The effect of such limitations, moreover, may change depending on the physical properties of the material used for nest construction.     

Flagellar sensillum patterns in Nyssoninae and Philanthinae wasps (Hymenoptera, Sphecidae)

Morphology and distributional patterns of antenna1 sensilla were compared between four species in three genera of Sphecidae. Sensilla placodea have plates that are raised to resemble low domes in Argogorytes mystaceus and A. fargei or low pegs in Bembix rostrata and Cerceris rybyensis . Sensilla basiconica occur in both sexes of Bembix and Cerceris , but, similarly to Apidae ( s. laf .), only in females of Argogorytes . The antennae of the two species of Argogorytes differ primarily in being larger in A. mysfaceus , thus permitting space for more sensilla. In Bembix rostrata , the male antennae are adapted to function as 'gripping' organs.     

Distal leg structures of the Aculeata (Hymenoptera): A comparative evolutionary study of Sceliphron (Sphecidae) and Formica (Formicidae)

The distal parts of the legs of Sceliphron caementarium (Sphecidae) and Formica rufa (Formicidae) are documented and discussed with respect to phylogenetic and functional aspects. The prolegs of Hymenoptera offer an array of evolutionary novelties, mainly linked with two functional syndromes, walking efficiently on different substrates and cleaning the body surface. The protibial-probasitarsomeral cleaning device is almost always well-developed. A complex evolutionary innovation is a triple set of tarsal and pretarsal attachment devices, including tarsal plantulae, probasitarsomeral spatulate setae, and an arolium with an internal spring-like arcus, a dorsal manubrium, and a ventral planta. The probasitarsal adhesive sole and a complex arolium are almost always preserved, whereas the plantulae are often missing. Sceliphron has retained most hymenopteran ground plan features of the legs, and also Formica, even though the adhesive apparatus of Formicidae shows some modifications, likely linked to ground-oriented habits of most ants. Plantulae are always absent in extant ants, and the arolium is often reduced in size, and sometimes vestigial. The arolium contains resilin in both examined species. Additionally, resilin enriched regions are also present in the antenna cleaners of both species, although they differ in which of the involved structures is more flexible, the calcar in Sceliphron and the basitarsal comb in Formica. Functionally, the hymenopteran distal leg combines (a) interlocking mechanisms (claws, spine-like setae) and (b) adhesion mechanisms (plantulae, arolium). On rough substrate, claws and spine-like setae interlock with asperities and secure a firm grip, whereas the unfolding arolium generates adhesive contact on smooth surfaces. Differences of the folded arolium of Sceliphron and Formica probably correlate with differences in the mechanism of folding/unfolding.     

The comparative distribution and population dynamics in Trinidad of Sceliphron fistularium (Dahlbom) and S. asiaticum (L.) (Hymenoptera: Sphecidae)

Two sphecid wasps, Sceliphron asiaticum (L.) and S. fistularium (Dahlbom), which build mud nests and capture spider prey, had overlapping but distinctly different distributions in Trinidad. Sceliphron asiaticum was associated with drier (<2000 mm mean annual precipitation) and less forested areas. The analysis of existing data on these species revealed a similar differential distribution throughout the neotropics. Based on the dissection of their old nests collected at 42 sites in Trinidad, retrospective life tables were constructed and estimates of fecundity made. Sceliphron asiaticum tended to form denser nesting associations and, while most of the common parasitoids were shared, had overall higher developmental mortality. Although such mortality was density-dependent in both species, where the two wasps nested together mortality from Melittobia (Eulophidae, Chalcidoidea) was higher in S. asiaticum . Both species were protarrhenotokous and had similar field fecundities (7–8/♀), but the rate of oviposition may be greater in S. asiaticum since far less mud was used in the construction of its cells. Both species had >50° mortality of the females between emergence and starting to nest. The regulation of numbers of these wasps in relation to that of S. assimile (Dahlbom) in Jamaica is discussed.     

A revision of the Australian digger wasps in the genus Sphex (Hymenoptera,Sphecidae)

The Australian species of the sphecid wasp genus Sphex are revised. Thirty-five species are recognized, of which 11 are new: Sphex argentatissimus, Sphex brevipetiolus, Sphex caelebs, Sphex corporosus, Sphex flammeus, Sphex fortunatus, Sphex gracilis, Sphex imporcatus, Sphex jucundus, Sphex latilobus and Sphex pretiosus. A dichotomous key covering all Australian species of the genus has been generated. The geographic distribution of all species is discussed based on all available locality records in relation to the Australian climate zones.     

The fauna of digger wasps (Hymenoptera: Sphecidae,Crabronidae) of Altai territory and the Republic of Altai

229 species of digger wasps from the families Sphecidae (13) and Crabronidae (216) were found in Altai Territory and the Republic of Altai. Five species are recorded for the first time for Russia: Podalonia alpina (Kohl), Spilomena differens Blüthgen, S. enslini Blüthgen, Ammoplanus serratus Tsuneki, and A. transcaspicus Gussakovskij; 36 species are recorded for the first time for West Siberia: Entomosericus kaufmani Radoszkowski, Mimesa crassipes A. Costa, Psenulus schencki (Tournier), Diodontus medius Dahlbom, D. minutus (Fabricius), Stigmus solskyi A. Morawitz, Astata jucunda Pulawski, Tachysphex latifrons Kohl, T. nitidus (Spinola), T. obscuripennis (Schenck), Nitela borealis Valkeila, Trypoxylon attenuatum F. Smith, T. deceptorium Antropov, Oxybelus aurantiacus Mocsáry, Lindenius ibex Kohl, L. parkanensis Zavadil, Crossocerus acanthophorus (Kohl), C. distinguendus (A. Morawitz), C. ovalis Lepeletier de Saint Fargeau et Brullé, Ectemnius rugifer (Dahlbom), Lestica pluschtschevskyi (F. Morawitz), Bembix bidentata Vander Linden, B. oculata Panzer, B. pallida Radoszkowski, Gorytes albidulus (Lepeletier de Saint Fargeau), G. procrustes Handlirsch, Sphecius antennatus (Klug), Bracystegus scalaris (Illiger), Philanthinus quatuordecimpunctatus (F. Morawitz), Cerceris albicolor Shestakov, C. angustirostris Shestakov, C. bracteata Eversmann, C. eryngii Marquet, C. fodiens Eversmann, C. impercepta de Beaumond, C. quadricincta (Panzer), and C. scutifera Shestakov.     

Sphecid wasps (Hymenoptera: Apoidea: Sphecidae) as potential control agents of acridid pests (Orthoptera: Acrididae) in Ethiopia

The possibility of using sphecid wasps to control acridid pests is discussed. A list of 19 Ethiopian species that could be utilized for this purpose is provided.     

A molecular phylogeny for digger wasps in the tribe Ammophilini (Hymenoptera,Apoidea, Sphecidae)

The evolution of parental care strategies in aculeate (stinging) wasps and bees has been much studied from a functional perspective, but relatively little phylogenetic information is available to place this in a rigorous historical context, especially at the species level. We used mitochondrial cytochrome oxidase I and two nuclear genes, the elongation factor‐1α and LW rhodopsin, to investigate the phylogeny of Sphecidae digger wasps. We focus particularly on the tribe Ammophilini, a clade of nonsocial apoid wasps that exhibit unusually diverse parental care strategies. We analysed a 2232 bp dataset for 40 ammophilines plus nine other taxa from within the remaining Sphecidae. Our Bayesian phylogeny provides strong support for the monophyly of Ammophilini and for the monophyly of all six individual ammophiline genera, except that the position of P. affinis within the genus Podalonia is only weakly supported. The monophyly of some, but not all, previously designated species groups within the genus Ammophila is supported. We discuss the implications of our results for the evolution of morphological traits used previously in ammophiline systematics.     

The behaviour of Philanthus crabroniformis (Hymenoptera: Sphecidae)

Observations were made over a two year period on the nesting and hunting behaviour of a population of Philanthus crabroniformis Smith. Data are presented on the time and speed of provisioning, the capture of prey and the species taken, the design and location of nests, the approach to the nest with prey, and aggressive interactions between females. P. gibbosus Fabr., also nested in the same area and took much the same prey. Unlike other sympatric pairs of Philanthus which have been studied, the two species in question were not totally segregated by separate nesting seasons nor by mutually exclusive habitat preferences. One aspect of the behaviour of the two Philanthus which was highly distinctive was the manner in which prey-laden females approached their nests. Selection for divergence in approach patterns may have been exerted by miltogrammine flies, a major parasite of many digger wasps.     

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

Although 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.     

Activity budgets, habitat use and body size in two coexisting species of sand wasps (Microbembex: Sphecidae, Hymenoptera)

ABSTRACT. 1. Two superficially similar species of Microbembex, M.monodonta (Say) and M.cubana Bohart (Hymenoptera, Sphecidae, Nyssoninae), occur syntopically on Staniel Cay, a small Bahamian island (15 km²).
2. Nesting (female) and territorial (male) aggregations of M.cubana were smaller and more numerous than those of M.monodonta in the study site and on the island as a whole.
3. Both species had regular patterns of daily activities that required them to use a variety of microhabitats in the study area.
4. Males of both species defended territories from c. 09.00 to 12.00 hours EST (in May) and the left to feed on nectar until they retired to sleeping burrows, typically from 13.00 to 15.00 hours. Male M.monodonta were active longer each day and intermixed feeding and territorial defence more than did male M.cubana.
5. Females of both species were active for longer each day, from c. 08.30 to 15.30 hours, and intermixed their respective activities – hunting for provisions, feeding, and nest digging and maintenance – during each day more than did males. Female M.monodonta were active longer each day, rising earlier and retiring later, than female M.cubana.
6. In M.monodonta , females were larger (length, X =11.00 mm) than males (10.5 mm). In M.cubana , males were larger (11.1 mm) than females (10.4 mm). Although mean differences were small, they were highly significant ( F =22.42; P <10⁻⁴) for the species-sex interaction.
7. Differences in activity budgets, habitat use, and sexual size dimorphism appear to be related. A combination of factors, particularly thermal constraints, possible competition, and different mating systems, could explain these patterns.