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The mature postdefecating larva of Trachypus denticollis Spinola is described. Larval morphology permits the separation of Trachypus Klug from Philanthus F., the two genera forming the subtribe Philanthina. The presence, in Trachypus, of maxillae with a pigmented lateral area represents an autapomorphy that allows recognition of the last larval stage of this genus.

The postdefecating larva (prepupa) of Stilbum cyanura (Förster) is described, illustrated and compared with the mature larvae of other Chrysididae. Analysis of the character states important for clarifying the phylogeny of this family are: (a) all abdominal segments divided/not divided into two annulets; (b) integument (1), atrium (2), opening into subatrium (3), mandibles (4), maxillae (5), maxillary palpi (6), and labium (7) with/without: (1) setae or spines, (2) asperities or weak lines on circumference, (3) spines; (4) setae on base, (5) spinules, (6) five apical sensilla, (7) papillose margin; (c) cranium with five or more/1–4/without pairs of setae; (d) antennal papillae: (1) longer/not longer than broader, (2) with two/three apical sensilla; (e) labrum with/without: (1) anterior edge notched, (2) sensilla, and (f) galeae highly/normally/poorly developed, show that the mature larva of Stilbum is characterized by the autapomorphy: antennal papillae with four apical sensilla. A few observations on a female of S. cyanura on the mud nest of its host, Sceliphron caementarium (Drury) (Hymenoptera: Sphecidae) showed that the cuckoo wasp, after an exploration phase to localize a host larva, create a hole in mud with its mouthparts and then insert the abdomen in this hole to oviposit in the host brood cell.

Territorial and agonistic behaviour in male sand wasps (Stizus continuus) was investigated in order to determine the influence of body size on territory maintenance and the strategies used to reduce the costs associated with territoriality. Size is the decisive factor in the capacity of males to defend a territory against other competitors: (1) in the disputes observed, the largest male was usually the winner; (2) territorial males were larger than those never seen occupying territories; (3) the size of males occupying territories that were left vacant when their inhabitants were removed experimentally was smaller. To optimize their territorial behaviour, males only defend sites in the nesting area and only when virgin females are emerging (from 0700 to 1300), and reduce the time spent perching (as opposed to patrolling) as temperature increases during the morning. To reduce costs associated with contests, males fight only with rivals of similar size and show a greater tendency to fight with larger males when virgin females are most likely to emerge (from 0800 to 1000). This suggests that males may be able to estimate the size of rivals immediately before an attack (face-to-face hovering), and leave when the opponent is significantly larger.

We report data obtained concerning the occupation of trap nests by xylicolous Crabronidae (sensu Melo 1999) in a study carried out in central Spain between 1992 and 1995. In particular, we analyze the data on the occupation of the nests for Psenulus concolor (Dahlbom), Trypoxylon attenuatum F. Smith, and Trypoxylon beaumonti Antropov. All three species use pre-existing cavities of 2-4 mm to establish their nests. The mortality rates varied between 33% and 55%, and of special interest was the variation between the two species of Trypoxylon L. and the absence of mortality due to natural enemies in P. concolor. In the three species, mortality was similar along the nests, with no increase in the innermost or outermost cells. Trichrysis cyanea (L.) was the most abundant natural enemy in the nests analyzed. Sex distribution was not random in any of the species studied: in P. concolor and T. attenuatum, the males developed in the outermost cells, while in T. beaumonti they appeared in the innermost ones. The sex ratio did not deviate from 0.5 in P. concolor and T. attenuaum, although in T. beaumonti, the number of females was significantly higher than that of males.

The contents of 21 trap-nests located in Sagarmatha National Park, Nepal, in 2002 and 2003 revealed interesting aspects of the biology of Ancistrocerus sikhimensis Bingham (Hymenoptera: Eumenidae). The nests included 2-7 brood cells separated by mud partitions. The dimensions of these structures seem to increase from the first cell to the last one constructed by the wasp. Females always used all the available space of the trap-nests, and the variability in the number of cells per nest essentially depended on their different dimensions. All the emerged adults were females, and we suspect that this species is bivoltine, with a highly shifted sex ratio between the two generations. In 2002, the parasite Chrysis sp. aff. coelestina Klug, recorded for the first time on this host, was responsible for a rate of parasitism per nest of 0%-100%, with an average of 41.65%. A second cuckoo wasp, Chrysis violenta ultramonticola Linsenmaier, emerged from one nest in 2003. Most A. sikhimensis females housed, mainly on the abdomen, hypopi of the mite Vespacarus sp., which is known to be involved in other wasp-mite associations. Unlike other mite-symbiotic eumenid wasps, A. sikhimensis does not present an acarinarium on its body to house the mites.

The mature post-defecating larva of Spilomena beata Blüthgen is described, and that of S. troglodytes Blüthgen is redescribed. Larval morphology permits the separation of Spilomena from Arpactophilus, two genera whose adults are morphologically very similar. However, after the recent description of the larva of Microstigmus nigrophthalmus Melo, there do not seem to be any characters that clearly differentiate the larvae of Microstigmus from those of Spilomena.

The exuviae of the final larval instar of three species of pimpline Ichneumonidae (Pimplinae: Delomeristini, Ephialtini), Perithous septemcinctorius (Thunberg), Zatypota bohemani (Holmgren) and Z. gracilis (Holmgren), are described. The mature larvae of Perithous Holmgren are characterized by presenting the maxillary and labial palpi with more than two sensilla. The exuviae of the different species that have been described in this genus, Perithous divinator, P. scurra and P. septemcinctorius, can be differentiated on the basis of the following characters: (a) presence/absence of spinules on the tegument, sensillum on antennal orbit, cardo; seta on posterior part of stipital sclerite; (b) presence/absence of number of setae on labrum, clypeus, maxilla, and postlabium, and sensilla on clypeus and labrum; (c) degree of development of epistoma; (d) number of sensilla of the maxillary and labial palpi (in the three species there are more than two sensilla), and (e) differentiation of the spinneret and salivary orifice. The most apparent differences between the exuviae of Zatypota Förster, Zatypota bohemani, Z. gracilis and Zatypota sp., are the expansion shown by the stipital sclerite at its lateral end and in the number, presence/absence and arrangement of the setae of the cranial sclerites (clypeus and labrum) and mouth parts (maxillae and labium). Descriptions of the cocoons of the two species of Zatypota and host records for all three species are reported.

The final instars of Eurytoma nodularis and E. heriadi are described and illustrated. Morphological structures of diagnostic value are discussed. The most salient character shown by the mature larvae of these two species lies in the mandibles, which are simple (unidentate), a feature that, according to current knowledge, is only shared with E. verticillata.

We studied the nesting behaviour and provisioning of Bembix merceti Parker and Bembix zonata Klug during three flight seasons (1993–1995). The females of B. merceti capture Diptera from seven different families to feed their larvae. Provisioning is progressive. The females provide a greater number of prey over subsequent days during larval growth. This activity begins increasingly earlier and lasts for longer, and prey capture is increasingly faster. Although the activity of the females is greater during the middle hours of the day, towards the end of each day the number of prey per wasp increases slightly and the duration of provisioning flights is reduced. Regarding Bembix merceti, we also report on nest structure and excavation as well as about the different natural enemies of these wasps. The data recorded for B. zonata refer to nest digging and structure, the wasps' natural enemies and their provisioning strategies, which in general are similar to those seen for the females of B. merceti.

The mature larva of Nemka viduata (Pallas) is described and illustrated. Morphological structures of phylogenetic value are discussed. The mature larva of this species is recognized by the followings traits: (a) head with parietal bands, (b) frontoclypeal suture distinct, and (c) labium with eight apical setae and two apical papillae. After further investigation, the presence of two apical papillae on the labium may represent an autapomorphy for the genus Nemka Lelej.

In a study carried out on Microstigmus thripoctenus on Barro Colorado Island (Republic of Panama) between March and May 1998, 29 active nests were located. The nests contained between one and seven cells, with one (female) to six (three females and three males) adults. Using simple manipulations in which wasps were offered a choice between experimentally emptied “foreign” nests and their own nest when the adults were away, it was observed that returning adults were able to recognize their own nest. Foreign nests were always rejected by females coming from nests with a single adult, whereas individuals from nests with several adults in five of seven cases did accept the foreign nests, continuing their normal activities in them, without destroying their contents. Adopted foreign nests were inspected at a higher rate following adoption. Nests containing several adults tended to remain longer on leaves supporting them, and their external surfaces were inspected more frequently and longer than those of nests containing only one occupant. Nests are not associated with any particular plant and were found attached to leaves of 19 species of understory plants.

The preimaginal stages of 14 species of Chrysidini—three postdefecating larvae (prepupae), nine mature larvae, two second-stage larvae, and nine first-stage larvae—are described. After analyzing for 33 selected characters, the character states observed in the mature larvae studied, several apomorphies are described that could characterize the groups Bethylidae, Chrysididae, Chrysidinae, and Chrysidini, as well as the genera Caenochrysis, Chrysis, Exochrysis, and Trichrysis. Second-stage larvae are very similar to mature larvae, those of the Chrysidini and Elampini being differentiated by the number of mandibular teeth. First-stage larvae display several morphological particularities derived from their cleptoparasitoid or parasitoid nature, emphasis being placed on the long antennae, the degree of development of setae on the labrum, the ventral position of the maxillary and labial palpi, the strong development of the mandibles, and the morphology of the last abdominal segment. For first-stage larv...

In a study carried out on Oxybelus lamellatus Olivier in eastern Spain, males emerge before females, patrolling the potential nesting area; they form mating balls and construct sleeping burrows. Females nest during the summer in dense aggregations on flat, sandy soils with almost no vegetation. They construct their nests mainly early in the morning. When excavating the nest, they push and rake soil, including the tumulus, which is leveled before provisioning begins. After the nest has been built, females orient by engaging in circular and figure-8 flights. The nest consists of an oblique main burrow with a single cell, although females may add cells later to an established nest. The prey (males and females of Diptera: Brachycera) are carried in pedal and abdominal transport. Pedal carriage was used for lighter prey, whereas abdominal carriage (sting-carrying) was used for those of greater weight; for prey weight/wasp width ratios between 3.10 and 3.40, both types of carriage were observed. Thirty-five species included in 9 families were caught as prey. Eggs are laid in a Crabro-type (sensu Iwata 1942) position.

The mature larvae of 2 species of Amiseginae— Adelphe anisomoiyhae Krombein and Mynnecomimesis bispinosiis (Riek)—are described. These larvae share with other Chrysididae and with Bethylidae a simple atrium and an opening toward the unarmed subatrium. As in the Bethylidae, they lack a coronal suture and parietal bands. Several characters are shared with Cleptinae and Chrysidinae (Chrysididae): a labrum with sensilla and a notched anterior margin, and a welldeveloped peritreme. The presence of 2 antennal sensilla, and the absence of setae on labrum and maxillae are, among the Chrysididae, exclusive to Amiseginae. The phylogenetic importance of these preimaginal structures is discussed.

The prepupa of Chalybion femoratum (Fabricius) is described and illustrated. The most salient character state shown by the mature larva of this species lies in the presence of scattered setae on the integument. Morphological characters with diagnostic value for the final instar of the tribe Sceliphrini are discussed.

The mature larvae of three species of Hoplitis, namely Hoplitis anceyi (Pérez), Hoplitis anthodemnion Michener, and Hoplitis nitidula (Morawitz), are described and compared with the other known larvae in the genus. The morphology of the spiracles, antennal discs, and antennal papillae, the absence of a seta on the mandibular basis, and the shape of the vertex permit the characterization of each species. Furthermore, H. anthodemnion has the integument covered by setiform spicules. Nevertheless, there is no clear separation between the three species studied and those previously known, and larval morphology does not support the consideration of Anthocopa and Hoplitis as separate genera.

The mature larva of the wasp Dinerus pictus is described. The ventral position of the anus, the absence of antenna1 papillae, and the weak development of the galeae, together with other minor differences in labrum, epipharynx, and parietal bands, clearly separate the larva of Dinetus from those of the tribe Astatini. Larval and adult characters do not support the inclusion of Dinetini in the Astatinae (sensu Bohart & Menke, 1976), and provide evidence in support of a relationship with the Laninae-Crabroninae complex.

Mature larvae of Chrysis angustula Schenk, 1856, and Hedychridium elegantulum Buysson, 1887, are described. A discussion of the phylogenetic importance of the preimaginal structures of known mature larvae of the Chrysididae is offered.

The mature larva of A. sikhimensis is described, illustrated, and compared with that of other species of the genus so far described. The final-instar of this species and the different species recently described, or redescribed, in this genus are A. kitcheneri, A. longispinosus, and A. trifasciatus, and all can be differentiated on the basis of the following characters: (a) the development of antennae; (b) the development of the atrium with respect to the subatrium; (c) the number of the sensilla of the labrum and galea, and (d) the presence/absence of spinules and papillae on the labium.

In a population of Philanthus pulchellus Spinola in eastern Spain, the males establish themselves in territories which they scent mark with pheromones to attract females. Females dig multdcelled nests, do not level the tumulus during excavation, and temporarily close nests during provisioning. They show low specificity in the capture of prey, which is represented by bees and wasps (including conspecific males and females). The mature larva is described and compared with others in the genus.

The mating systems of mutillid wasps have rarely been studied. Here we present information on the mating system of Nemka viduata. At a site in southern Spain, many males of this species were seen flying over host (digger wasp) nest aggregations while searching for females. Male activity was greatest in the early morning and late afternoon, when females were more active searching for hosts, and on days when relatively large numbers of females were active. Males were not territorial but instead attempted to find emerging females before their competitors. As many as six males might arrive at a receptive female more or less simultaneously. Struggles to control access to females continued until one male copulated with the female on the ground or carried it off in flight to a location away from rival males. Male size seems to affect the patrolling behaviour (number of patrolled sites), but there is little evidence of an advantage for larger males, as expected in a scramble competition mating system. Scramble competition mating systems often evolve in species in which large numbers of males compete for scarce receptive females, a factor that makes male territorial defence of large areas highly costly.

The frequency of superparasitism and its effects on the quality of laboratory-rearedSpalangia cameroni(Hymenoptera: Pteromalidae) parasitoids were investigated under laboratory conditions. Numerous variables were measured, such as the number of ‘ovip holes’ per host as a measure of superparasitism. Adult emergence and sex ratio, as well as female size, emergence ability from soil and longevity were also measured. Finally, an assessment was made of fertility and survival of adult parasitoids emerging from the medflyCeratitis capitata(Diptera: Tephritidae) pupae with different levels of superparasitism. A high frequency and prevalence of superparasitism under laboratory rearing conditions was observed. The number of ‘ovip holes’ per host ranged from one to 17, with an average (±SD) of 2.8±3.4. Sex ratios became increasingly female-biased with increasing levels of superparasitism, although overall levels of wasp emergence (male, female) declined. Nevertheless, no relationship was discerned between female size and level of superparasitism. The ‘emergence ability from the soil’ was higher in those parasitoids that emerged from strongly superparasitized hosts, but not related to the type of substrate in which the host pupae were buried. The level of superparasitism did not have a significant effect on the longevity, fertility and survival of female parasitoids. Our results support the hypothesis that superparasitism inS. cameronimight be adaptive, since attributes such as ‘emergence ability from the soil’, longevity, fertility and survival were not affected by the level of superparasitism or the presumably detrimental effects derived from physical combats among conspecific larvae. Our findings are relevant to recommendations for rearingS. cameronifor biological control releases, as well as shedding light on superparasitism under both laboratory and field conditions.

In the western Mediterranean, 772 species of bees in the family Megachilidae have been reported. Special emphasis has been placed on the Iberian Peninsula, where to date 218 species are known. However, few intensive studies providing information about communities of Megachilidae have been carried out. Two earlier works cite 70 species; almost one third of those known on the Peninsula. With an aim of gaining insight into the structure of the communities of Megachilidae and the factors influencing them, an analysis was made of the alpha and beta diversity of different localities in the northern subplateau. Malaise traps (black and white) were used, and 559 specimens belonging to 55 species were identified of which most exhibited a nest-holder-type nesting habit. Abundance and richness were higher for white traps, although a considerable degree of complementarity was observed with the black traps. In the study zone, diversity can be considered medium-high with a phylogenetic diversity corresponding to stable populations. Regarding the composition of the Megachilidae communities, the influence of the landscape structure, of the microhabitat, and of the colour of the trap used to collect the specimens was detected. The following are recommended: (1) the use of both black and white traps, since they show high complementarity and offer different information about community structure, (2) homogenization of the samples in comparisons among communities, owing to the influence of the color of the trap, which masks the importance of ecological factors in community structuring, and (3) the collection of samples from at least two years previous, in view of the elevated “replacement” of species observed with species richness estimators.

In this work, we study the suitability of using dead medfly Ceratitis capitata pupae, killed by heat- or cold-shock, for the mass rearing of Spalangia cameroni, a pupal parasitoid of key pests. 100% mortality of medfly pupae could be accomplished with cold-shock at -20 degrees C for 60 min or with heat-shock at 55 degrees C for 30 min. Neither parasitism percentage nor sex ratio of the offspring differed significantly among heat-shocked, cold-shocked and untreated pupae. In addition, there was no significant difference in the percentage of parasitoids that aborted (male male or female female) among pupal treatments. Some of the pupae were covered with peat because the third larval instar of the medfly buries itself before pupation. However, the buried pupae were not parasitised at a greater or lesser rate than those not covered with peat. The percentage of parasitism was also unaffected by whether the pupae had been killed recently or had been stored at between 4 degrees C and 6 degrees C over 15 or 30 days. The use of dead hosts and later storage permitted the following: (a) the use of hosts over long periods of time; (b) a rapid increase in parasitoid numbers and (c) the availability of pupae killed at the most suitable postpupation times for the production of parasitoids. Furthermore, in biological control projects, the use of dead parasitised pupae in the field avoids the risk of enhancing the pest and allows an increase in parasitism in the field through the use of pupae treated with cold- or heat-shock.

The position of the emerging point has rarely been investigated as a factor possibly affecting the future nest settlement behaviour in Hymenoptera, in particular within nest aggregations. We studied the emergence and dispersion patterns of the digger wasp Stizus continuus. Individuals emerged daily in clumped patterns, possibly revealing a certain synchrony of emergence from the same nests, and protandry appeared both at seasonal and daily level. Differences between the number of females that nested relatively close or far from their emergence holes (EH) were either significant or not, depending on the year, and observed dispersal distances from the natal nests did not differ from those obtained by random simulations. By contrast, females nested close to the nearest conspecific nest. Size did not affect the dispersion patterns. EH are thus not important cues for nest establishment, and conspecific nests are probably the key cue for nest-founding females. In addition, males did not prefer to establish territories close to their natal nest.

Between 1997 and 2005, a study was made of the Chrysididae, Eumeninae, and Spheciformes wasps in the Arribes del Duero Natural Park (Provinces of Salamanca and Zamora, western Spain), a highly heterogeneous Mediterranean landscape. We collected, respectively, 127, 57, and 230 species of these groups, constituting approximately 50% of the species known for the Iberian Peninsula. The inventory was fairly complete according to the final slope of the species accumulation curves. From a biogeographic point of view, the predominant elements of the Arribes del Duero fauna are Mediterranean in the broad sense, together with a high percentage of species of Euro-Atlantic distribution. The proportion of endemic species obtained is similar to those known for the whole of the Iberian Peninsula. The species endemic to the northern subplateau and to the southwestern quadrant predominate. The Arribes del Duero territory is the northern limit of the distribution of some Iberian-Maghrebine species, although it is also the southern limit of species widely distributed throughout central and northern Europe. The Atlantic influence in the territory has facilitated the persistence of some species, with an Atlantic or sub-Atlantic distribution, related in particular to riparian forests. This space constitutes a large eco-corridor that joins the north of the Peninsula to the south, linking communities corresponding to the Eurosiberian and Mediterranean biogeographic regions and to territories encompassed within the Temperate and Mediterranean macrobioclimates. Thus, because of its geographic situation and extensive latitudinal range, together with the fact that it has a good representation of European biodiversity, the Arribes del Duero Park is proposed as a priority area for insect diversity conservation in the Mediterranean region.

The development and morphology of the immature phases of Spalangia cameroni Perkins, 1910 (Hymenoptera, Pteromalidae) are described from a laboratory rearing culture maintained on Ceratitis capitata (Wiedemann, 1824) (Diptera, Tephritidae), using microscopic techniques, including light and scanning electron microscopy. The surface of the chorion of the egg is smooth and the micropyle occurs at the anterior end. The immature larvae are similar to the mature larva, differing mainly in the size of the head capsule and mandibles. The mature larva displays tubercules on the body segments as well as a pleurostoma and superior and inferior mandibular processes. On completion of its larval development, an adecticous and exarate pupa is produced. The mandibles of the pupa, as for the adult, are toothed. Three larval instars are recorded based on statistical analyses of the sizes of the larval mandibles and head capsules, in combination with such characters as the number of exuviae and excretion of the meconium. There are significant positive correlations between mandible length and width of larval head capsule with the number of instars, thus indicating that the mandible length and width of larval capsule are good predictors of the number of instars in this parasitoid. Developmental time from egg to adult emergence was approximately 33-34 days for females and approximately 28-29 days for males at 21-26 degrees C, 55-85 RH and a L16:D8 photoperiod. Our results show that the eggs and different instars of S. cameroni can be unambiguously identified only by SEM. Therefore, characterization of the immature stages of Spalangia species using SEM should be done before subsequent routine identifications using a binocular microscope or stereomicroscope.

A study of the biology of Stizus perrisii ibericus revealed some aspects about the behaviour of males, the nesting behaviour of females, and larval development. The slow mass provisioning of this species is compared with the provisioning behaviour of S. continuus and S. pulcherrimus. Cocoons are constructed in seven stages although, compared with other species, there are differences in the duration of each stage. Natural enemies of the wasp include miltogrammine flies, several cuckoo wasps, and velvet ants.

The preimaginal stages of T. peregrina are described. The egg displays a sculptured chorion, which is found only on those deposited externally. The immature larvae are characterized by their peculiarities in (a) a setose ring on the thoracic and abdominal segments, (b) an anal notch and (c) size and the sensory structures of the head capsule. The final instar is described and illustrated. Morphological structures of diagnostic value are discussed. The most salient character shown by the mature larva of this species lies in the epistoma, which is complete. Resumen. Se describen las fases de huevo y larva de T. peregrina . El huevo, como es característico en los que se depositan externamente, presenta un corion ornamentado. Las larvas inmaduras exhiben peculiaridades en (a) el anillo setoso de los segmentos torácicos y abdominales, (b) la escotadura anal y (c) el tamaño, y estructuras sensoriales, de la cápsula cefálica. El estado de carácter más sobresaliente presentado por la larva madura de esta especie radica en la presencia de un epistoma totalmente diferenciado.

Observations of a female of Prionyx kirbii at an aggregation of Stizus continuus revealed an alternative nesting behaviour of the first wasp due to the presence of the second one. The overlap of some resources (prey, kind of soil) allowed P. kirbii to act as a kleptoparasite of S. continuus. The observed female often re-used as nests pre-existing S. continuus emergence holes, but no S. continuus nests. The prey were obtained sometimes by stealing the grasshoppers from S. continuus nests and/or by attacking the females while carrying the prey. From a review of interspecific kleptoparasitism among sphecoid wasps it appears that family Sphecidae includes the highest number of facultative parasitism cases and this finding is discussed. In addition, the description of the prepupa of P. kirbii is given and is shown to be in agreement with the description of the mature larvae of the other species of the genus.

The mature larvae of Chrysis gracillima Forster, 1853 and Omalus biaccinctus (Buysson, 1893) are described and compared with others known in the tribes Chrysidini and Elampini, respectively. Additionally, new data are reported on the biology of Trichrysis cyanea (L., 1758).

Data on the nesting behaviour of Tachysphex albocinctus (Lucas), T. consocius Kohl, and T. tarsinus (Lepeletier) are presented. T. alhocinctus uses immature mantids as prey, and their males exhibit territorial behaviour; T. consocius and T. tarsinus prey on nymphal acridids. The mature larva of T. tarsinus is described.