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.     

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.     

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.     

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.     

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.     

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.     

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.     

Carbohydrate bait preferences of wasps (Vespula vulgaris and V. germanica) (Hymenoptera: Vespidae) in New Zealand

Abstract

Carbohydrates are both a source of food and a potential bait for control of common and German wasps. Carbohydrate preferences of wasps were determined in a series of paired trials by counting the number of wasps caught in traps baited with carbohydrate‐based baits versus a standard protein‐based bait. Factors influencing wasp attraction to carbohydrate‐based baits included bait type, season, weather, and location. A 30% sucrose solution was more attractive than honey, jams, gels, or dry (solid) sugars. The sucrose solution was more attractive in spring and autumn than in summer, probably because rainfall washed away natural carbohydrate supplies. There was a significant relationship between rainfall in the previous week and the proportion of wasps caught in traps baited with sucrose solution versus sardine cat‐food. A higher proportion of German wasps than common wasps was caught in sucrose‐baited traps. This may have been related to seasonal differences in abundance and/or behavioural differences between the two species. In some locations, more wasps were caught in traps baited with sucrose solution than in those baited with sardine cat‐food. The proportion of wasps caught in sucrose‐baited traps was higher in locations without beech scale honeydew than with beech scale honey‐dew. Proportionally more non‐target species (mainly honey bees) and fewer wasps were caught in traps baited with sucrose solution than in those baited with sardine cat‐food. All five bee repellents tested also repelled wasps. These results indicate the importance of determining the bait preferences of wasps (carbohydrate or protein) and the presence of non‐target species before attempting a poison‐baiting operation. They also emphasise the need for a wasp‐specific carbohydrate‐based bait.     

A cladistic analysis of the subfamily Philanthinae (Hymenoptera: Sphecidae)

Abstract. The Philanthinae, as treated here, contains the eight valid genera Aphilanthops Patton, Cerceris Latreille, Clypeadon Patton, Eucerceris Cresson, Philanthinus Beaumont, Philanthus Fabricius, Pseudoscolia Radoszkowski and Trachypus Klug. Listropygia Bohart is synonymized with Clypeadon , syn.n. The genera Eremiasphecium Kohl and Odontosphex Arnold are removed from the Philanthinae and regarded as genera incertae sedis within Sphecidae. Analysis of the genera of this redefined subfamily Philanthinae finds two major clades whose monophyly is strongly supported: ( Philanthinus + ( Philanthus + Trachypus )) [= Tribe Philanthini] and ( Pseudoscolia + ( Cerceris + Eucerceris )) [= Tribe Cercerini]. There is some evidence for the monophyly of Clypeadon + Aphilanthops [= Tribe Aphilanthopini]. Cerceris and Philanthus are inferred to be paraphyletic with respect to Eucerceris and Trachypus , respectively. Philanthinus is removed from the tribe Aphilanthopini and placed in the tribe Philanthini, and the monotypic tribe Pseudoscoliini is synonymized with Cercerini.     

Redescription of Heterogyna protea Nagy (Hymenoptera: Sphecidae; Heterogyninae)

ABSTRACT. The type-species of, i>Heterogyna Nagy, 1969, is redescribed from the unique male holotype, in relation to four other species recently described.     

The male of Sceliphron pietschmanni Kohl, with notes on its biology, and a note on homonymy in S. jamaicense (F.) (Hymenoptera: Sphecidae)

The male of Sceliphron pietschmanni is described and notes are given on the biology of the species. The supposed homonymy of S. jamaicense is discussed.