Sociogenetic structure of Polistes (Aphanilopterus) versicolor Olivier, 1791 colonies (Hymenoptera, Vespidae, Polistini)

The observation of two distinct, well-defined oviposition areas in nests of the primitively eusocial wasp Polistes versicolor suggests the presence of multiple egg-layers and territorial behaviors. Electrophoretic analysis of enzyme loci in pupae from 35 colonies revealed an average observed heterozygosity of 0.10 and the existence of private polymorphisms, thereby indicating a low dispersion in this species. No evidence of diploid males was found. Phenotypic segregation analysis revealed the presence of more than one egg-laying female in 15 out of 35 colonies, as well as spatially preferential oviposition in 2 out of 13 nests, with distinct oviposition areas. Genetic relatedness estimates for brood were lower than expected for haplodiploid species under monogynous conditions (r = 0.75 for female broods and r = 0.5 for male) in 4 of those 13 nests, thereby inferring complex sociogenetic structuring in Polistes versicolor colonies.     

A new psychodid species from Saban tank bromeliads

A new species of Neotropical Psychodidae, Alepia apexalba sp. nov., is described from dry-forest tank bromeliads in Saba, Netherlands Antilles. Larvae, pupae and adults are described and figured. It is possible to relate larvae and adults because the latter were reared from pupae collected from the bromeliads (Tillandsia utriculata) that also contained larvae. Bromeliads are adapted to intercept canopy litter and throughfall water, and decaying litter is washed into and retained by the leaf bases. It is from this aquatic habitat that the larvae and pupae were collected.     

Sequestration and metabolism of host-plant flavonoids by the Pale Grass Blue, Pseudozizeeria maha (Lepidoptera: Lycaenidae)

Flavonoids in the eggs, larvae, pupae and adult butterflies of Pseudozizeeria maha were identified and quantified. Isovitexin (apigenin 6- C -glucoside) was the dominant flavonoid detected in pupae and imagines, whereas saponarin (isovitexin 7- O -glucoside) was the dominant flavonoid in larvae. Saponarin, biotransformed from isovitexin by the larvae, was found to be reconverted into isovitexin at the pupal stages. The total amounts of accumulated flavonoids differed between sexes, particularly in adults where the bodies of females had a much higher flavonoid concentration than that of the males. These flavonoids were also detected in the eggs. These results indicate the possibility that flavonoids are utilized in not only wing coloration but also as a chemical defense compound against natural threats.     

西藏波密柑马蜂的筑巢习性（英文）

柑马蜂Polistes mandarinus在不同的环境中会利用植物材料制作各种不同的蜂巢。我们在2009年5-8月间观察研究了西藏自治区波密县的柑马蜂筑巢习性, 并收集62个蜂巢。柑马蜂利用植物纤维和树脂将它们的巢穴筑于当地居民的木屋檐下。收集的42个在用蜂巢中, 8月末平均拥有79.64±65.28个蜂房, 13.1±10.68个蜂蛹。20个弃用蜂巢中, 平均拥有12.95±3.99个蜂房。8月末, 成功的柑马蜂群拥有约80个个体。研究地的柑马蜂采取3种方式来筑巢, 但以第1种方式最为普遍。第1种筑巢方式筑造的蜂巢以两个蜂房连接巢柄, 结构最为稳定, 所以也应用最广, 后两种筑巢方式筑造的蜂巢均以一个蜂房连接巢柄, 是由于越冬雌蜂在找不到合适的筑巢材料时才采取的建巢方式。     

Colony structure and nest characteristics of European wasps, Vespula germanica (F.) (Hymenoptera: Vespidae), in Victoria, Australia

Abstract European wasps, Vespula germanica , are common across southern and south-eastern Australia and have a negative impact upon urban areas, primary industries, and natural ecosystems. Aspects of colony structure and nest characteristics are examined for nests located in the ground and collected from urban and rural sites in Victoria during two summer−autumn field seasons (1996 and 2001). On average, nests were located 28 cm beneath the surface (range 5−58 cm). The average number of combs in the nest and the total area of the nests increased from early February to late May. In addition, the proportion of cells used to produce workers and different life stages (larvae, pupae) also varied throughout the season; being consistent with studies from New Zealand. No differences in colony structure or nest character­istics were detected between urban and rural nests.     

Isozyme differences between the developmental stages of the parthenogenetic gall wasp Diplolepis rosae

The value of electrophoretic analysis of enzymes as an aid in connecting a morphologically deviating form to one of several possible species is dependent on the proportion of shared enzyme loci between the forms. In order to determine this proportion for the different instars of the parthenogenetic gall wasp Diplolepis rosae, 16 different enzyme systems were analysed. Out of the 37 loci detected, 25 (68%) were active in all instars. The larvae, pupae, and imagines had two, one and five unique loci, respectively. Larvae and pupae shared four loci not expressed in the imagines. In the ten enzymes analysed for comparison of males and females a total of 22 loci were detected, 21 found in both sexes and one unique to the females. The difference in isozyme pattern was found to be much more pronounced between pupa and imago than between larva and pupa. The chance to find a locus in an instar when already detected in another was calculated to 87%. If this estimate is valid for other forms within species, differential activity should not present a problem when electrophoretic analysis is used in order to connect such forms.     

Queen brood reared in worker cells by the social wasp,Vespula germanica (F.) (Hymenoptera: Vespidae)

Summary The rearing of queen brood from worker cells in the nests ofVespula germanica (F.) in Australia was found at all stages of the colony cycle from early summer to autumn. Worker cells used to rear queens were 17% wider at their open ends than cells used for worker production, and in all other respects their dimensions were greater. The volume of a worker cell used for queen nearing was 21% larger than cells used for rearing workers but half the volume of a normal queen cell. Queen pupae reared in worker cells were significantly smaller than those reared in queen cells of the same nest. The spatial distribution of queen pupae in worker comb tended to be random although some evidence of nonrandom clustering was noted.The significance of this phenomenon is discussed in relation to caste differentiation and queen-control of gyne initiation and production. It is concluded that the phenomenon is neither seasonal nor due to some intrinsic component of the colony's annual cycle, and that it is unlikely to be an emergency queen-rearing response. Development of queens in worker cells may have occurred during favourable feeding regimes, perhaps determined by the benign Australian environment.     

Decision-making conditions for intra- or inter-nest mating of winged males in the male-dimorphic ant <Emphasis Type="Italic">Cardiocondyla minutior</Emphasis>

Only winged male and female ants generally mate through nuptial flight during the reproductive season. In the ants of Cardiocondyla, the males show wing dimorphism and their reproductive strategies differ depending on the differences in wing morphology. It has been suggested that wingless “ergatoid” males bearing very similar external morphologies to workers mate within natal nests, whereas winged males bearing typical ant male morphology disperse from their nests to mate. However, some behavioral observations suggest that the winged males of some Cardiocondyla ants such as C. obscurior and C. minutior may mate within natal nests before dispersion. We evaluated the factors affecting the mating behaviors of the winged males of C. minutior under laboratory conditions. We found that (1) the winged males remained and mated with virgin females in natal nests when either virgin winged females or the relatively mature pupae of winged females (i.e., at least 10 days) were present in the nest, (2) the winged males dispersed to adjacent nests with virgin winged females when only mated queens and the relatively young pupae of winged females (i.e., <9 days) were present in the nest, and (3) all winged males were accepted by the workers of non-natal nests irrespective of the distance from the natal nests in the field. Although most ergatoid males were accepted by the workers of close non-natal nests, they were all attacked and killed by the workers of distant non-natal nests. These results suggest that intra-nest mating and the dispersion of the winged males of C. minutior are facultatively determined by the condition of winged females (virginity and relative pupal age) in natal nests. Furthermore, our results suggest that winged males are likely to seek mating partners chemically and to mate with virgin winged females.     

An exceptionally high diversity of hoverflies (Syrphidae) in the food of the reed warbler (Acrocephalus scirpaceus)

Despite being considered a classical example of protective Batesian mimicry hoverflies (Syrphidae) are known to be preyed upon by various passerines. The aim of the present study was to examine in detail food brought by reed warblers Acrocephalus scirpaceus to their nests to better understand the importance of hoverflies in the diet of small passerines. Using neck collars, 273 food samples containing 8,545 food items delivered to reed warbler and parasitic common cuckoo Cuculus canorus nestlings in warbler nests were recorded. The study was conducted during three breeding seasons in South Moravia, Czech Republic. An unusually high diversity of hoverflies was found — 27 species, including Mesembrius peregrinus (critically endangered species in the Czech Republic) and Mallota cimbiciformis (endangered species) — a new taxon to the Czech Republic. This indicates that nestling diet analyses may provide not only information on avian foraging behaviour but also important faunistic data. Thus, without the detailed identification to species level of material from foraging behaviour studies valuable scientific information may be lost. Overall dominance of Syrphidae was 3.7%, the most common species being Episyrphus balteatus (55.7%, n = 318). However, this number seriously underestimates the importance of hoverflies in the diet of reed warblers as hoverflies are one of the largest prey taken by warblers. Both larvae and pupae were rare, imagines strongly dominating (92.7%). Both specific wasp mimics (e.g., Chrysotoxum verrali) and bee mimics (e.g., Eristalis spp.) were not avoided by foraging reed warblers. The presence of a parasitic cuckoo chick did not affect host foraging behaviour with respect to overall dominance of hoverflies in the diet (warbler 3.3%, cuckoo 3.8%).     

Colony development and social structure in a subtropical paper wasp,Ropalidia fasciata (F.) (Hymenoptera: Vespidae)

More than 50% of nests of Ropalidia fasciata were founded by association of foundresses (multifemale nests). The multifemale nests were generally initiated earlier and grew faster than the single-female nests. The survival rate of the multifemale nests was significantly higher than that of single-female nests, and the productivity as measured by the number of cells produced per foundress had a peak at a foundress-group size from 6 to 10. The number of marked foundresses which were seen on their original nest decreased as the colony cycle proceeded, but some of them continued to coexist on the original nests after emergency of many female progeny. Except in the case where a large number of foundresses attended a young nest so that some foundresses could not sit on the nest, the dominance interactions among cofoundresses were mild. More than twothirds (71.4%) of nests (including those at the post-emergence stage) had multiple egg-layers. The foundress association in this species is considered to be beneficial for every foundress because it raises ability to avoid predation or to reconstruct their nests when the nests are destroyed by typhoons.     

When food fights back: Cebid primate strategies of larval paper wasp predation and the high-energy yield of high-risk foraging

Optimal foraging theory predicts that well-defended potential foods should be exploited only when energy pay-offs are great. Although stinging hymenopteran nests are both well-defended and predated by primates, their larvae's energy yields rarely have been calculated, and predation-linked foraging behaviours by primates infrequently documented. Based on 58 opportunistic observations of primates raiding wasp nests for larvae, we calculated energetic yields of low- and high-risk wasp nest predation for Cebus albifrons, Saimiri collinsi, S. sciureus and Sapajus apella, and tested predictions derived from optimal foraging theory. We recorded how nests were processed and by which age-sex classes, eaten nest fragment sizes, number of occupied and empty cells, and nest occupancy patterns (percent larvae/pupae, eggs, empty cells). Basal metabolic rate (BMR) calculations showed energetic yields from 15 min foraging on low-risk nests (Polybia quadricincta) would meet energy needed to sustain adult female and male C. albifrons BMR for 4.9 and 4.5 h, respectively; yields from high-risk (Chartergus artifex) nests for 6.5 and 6.2 h; Mischocyttarus sp. nest yields (low risk, but mimetically resembling other wasps) would meet S. collinsi BMR for 2.9 h (female) and 2.3 h (male), and 2.6 and 2.1 h, for the slightly larger S. sciureus, respectively. The Chartergus energetic-yield value is nearly 20% of a 36 g chocolate bar (741 kJ). Our data provide quantitative support for the common assertion that wasp larvae and pupae are high-yield foods for primates. As predicted by optimal foraging, energetic yield is sufficient to offset the risk and pain of being stung.     

Aspects of the biology of Glaciopsyllus antarcticus (Siphonaptera: Ceratophyllidae) during the breeding season of a host (Fulmarus glacialoides)

Summary The breeding period of the Antarctic flea, Glaciopsyllus antarcticus (Smit and Dunnet), was synchronised with the breeding period of the host, Southern Fulmar (Fulmarus glacialoides Smith). Although eggs were laid in the host nest, larvae developed amongst the down (particularly on the belly) of host chicks. Larvae were blood feeders and pupated amongst the down of host chicks. The development of pupae was arrested by ambient temperatures (mean temperature of +2.5°C in January), but recommenced when pupae were warmed. Female fleas comprised 55.8% of a collection of 1988 adults. Low numbers of adult fleas were found in nests prior to host breeding and subsequent to host fledging in comparison to numbers on the host; adults are therefore presumed to overwinter on the host, remote from the nest.     

Host nest preference and nest choice in the cuckoo paper wasppolistes sulcifer (Hymenoptera: Vespidae)

Polistes sulcifer is a cuckoo paper wasps, an obligate social parasite which must usurp a colony of another species in order to reproduce. Field data show thatP. sulcifer females usurp exclusively nests belonging to one species only (P. dominulus). Moreover, they are more frequently found on large and puparich nests. A series of laboratory trials, in which parasite females were offered a binary choice of nests with different characteristics, confirm both the species specificity betweenP. sulcifer andP. dominulus and the parasite's preference to usurp larger nests containing pupae. The data support the hypothesis thatP. sulcifer females choose between available nests. The biological meaning of these findings is discussed.     

A report of progressive provisioning in a stink bug,Parastrachia japonensis (Hemiptera: Cydnidae)

The majority (75%) of femaleParastrachia japonensis (Hemiptera: Cydnidae), while caring for 1st and 2nd instar nymphs, foraged for and provisioned nests with drupes of the host plant,Schoepfia jasminodora (Olacacae), which the young then fed on. The maximum number of drupes found in a given nest was 27. Females could travel as fast as 61.4 cm/min while carrying drupes that were nearly double their weight, and were directly observed to travel as far as 10 m when encumbered with a drupe. It was found that nests which were far from the food source were provisioned with at least as many drupes as those nests that were within the drupe range. While females could not distinguish their own eggs from others, apparently they could distinguish their own nests containing their nymphs. Eggs failed to survive in the absence of a female, however, a small number of nymphs reached adulthood even in the absence of a female when drupes were provided. This report represents the first direct observation of progressive provisioning by a phytophagous hemipteran under field conditions.     

The influence of X-rays on reproduction in Pseudeucoila bochei (Hymenoptera Cynipidae), a parasite of Drosophila melanogaster

The parasitic wasp Pseudeucoila bochei was the subject in experiments designed to detect a reliable method of mutation induction. Radiation doses of 360, 720, 1080, 1440, 1800 and 2160 R were given to pupae 15 or 18 days old or to freshly eclosed male and female wasps. The irradiation did not influence the survival of pupae. Dose-action responses were established and appeared to be dependent on the stage of development of the wasps at the moment of irradiation. The production of sons by virgin females showed that the germ cells of the adults were the most sensitive to irradiation. In contrast, the sperms of the male wasps irradiated as adults were the most resistant. Irradiation of males as pupae with 1880 or 2160 R on the 15th day or as adults led to a high frequency of amle progeny. The elimination of sperm cells from fertilization is discussed. Comparisons with Habrobracon, Nasonia and Drosophila showed that the germ cells of Pseudeucoila are more sensitive to irradiation. In the progeny from irradiated females and males 2 types of mutant were found, with yellow eye colour and with aberrations in the antennae.     

Offspring genetic structure reveals mating and nest infestation behaviour of an invasive parasitic fly (<Emphasis Type="Italic">Philornis downsi</Emphasis>) of Galápagos birds

The natural reproductive behaviour of invasive insects is pivotal knowledge for managing species of ecological or economic concern. We use microsatellites to examine female multiple mating and multiple nest infestations in the introduced parasitic fly, Philornis downsi, which causes high mortality in endemic birds on the Galápagos Islands. We analyse larvae and pupae within 57 nests from Santa Cruz and Floreana Islands in both the highland and lowland habitats. Sib-ship reconstructions of offspring revealed that up to five females may infest a single nest, while multiple mating in females was frequent (65% of reconstructed maternal genotypes), with an average of 1.91 (±0.06 SE) males per female. Genetic relatedness (R) of offspring within nests was generally low, though lowland nests on Floreana had higher R than highland nests. Knowledge of the reproductive behaviour of P. downsi is necessary for modelling appropriate management strategies, in particular, the sterile insect technique, for which success is greatly influenced by female multiple mating.     

Few, small, and male: multiple effects of reduced nest space on the offspring of the solitary wasp, Euodynerus (Pareuodynerus) posticus (Hymenoptera: Vespidae)

The size of the preexisting wood cavities used as nests by aculeate Hymenoptera is expected to have consequences on fitness parameters such as offspring number and size. We evaluated the consequences of using small and large (three-times more voluminous) trap-nests by the solitary wasp, Euodynerus (Pareuodynerus) posticus (Herrich-Schaeffer). Following life-history and sex allocation theories, a number of non-mutually exclusive hypotheses were formulated: i.e. small nests either produce smaller or fewer offspring and/or more males, the cheaper sex. Wasps built about 28% more, but shorter brood cells in large nests, although their volume was still much higher in large nests. Adult males had smaller body size in small nests, but female size did not differ between large and small nests, possibly as an adaptive response against the future higher foraging costs of size-reduced females. Sex-ratio was often biased towards males in small nests. Mortality did not differ between large and small nests. We conclude that E.?(P.) posticus females would benefit from using larger nests, but that the sex-ratio would be probably overall unbalanced if females would not use also smaller, male-oriented tunnels.     

Construction of Nest Defensive Structure According to Offspring Value and Its Effect on Predator's Attack Decision in Paper Wasps

Various organisms are known to build nests with defensive structures to protect their offspring from predation, but our understanding of plasticity in the nest structure remains poor. In this study, we investigated whether a paper wasp, Polistes chinensis antennalis, adjusted the construction of nest defensive structure according to the value of their offspring, and we also analysed the effect of adjusting the construction of the structure on predator's decision to attack. P. chinensis antennalis foundresses start a colony and maintain her nest alone until the emergence of workers. During this stage, foundresses often construct a defensive structure on cocoon caps of pupae using nest materials (pulp), which prevents predation of pupae by conspecifics from other nests. The value of pupae to the foundress varies among those in a nest, where the value is higher in pupae that spun the cocoon (and initiated pupation) earlier than other pupae in the nest. From field observations, we found that foundresses constructed a larger pulp structure on the cocoons of pupae that cocooned earlier in the order of cocoon spinning, even after considering confounding factors. We also found that the probability of a pupa being attacked by conspecific intruders decreased with the size of pulp structure on the cocoon. This indicates that intruders avoid attacking cocoons with larger pulp structures. Our study indicates that foundresses adjust the construction of nest defensive structures according to their offspring value, and this allows them to protect the high‐value offspring efficiently and effectively.     

Characteristics of Crataerina pallida (Diptera: Hippoboscidae) populations; a nest ectoparasite of the common swift, Apus apus (Aves: Apodidae)

An essential pre-requisite to understanding the nature of a host-parasite relationship is a good knowledge of the parasite’s ecology, including its life history. Despite removing a significant amount of blood from their common swift (Apus apus) hosts, no detrimental effect of parasitism by the louse fly (Crataerina pallida) has been found. This may be because little is known of the characteristics of the populations of this parasite. We studied the structure of louse fly populations that may influence its pathogenicity. High levels of prevalence were seen, with 100% of nests being parasitized during 2007 and 2008. Louse fly pupae were found to be aggregated, with a frequency distribution best described by the negative binomial model in 2006-2008. The mean parasitic load per nest was 3.72 ± 2.65 in 2007 and 4.21 ± 3.09 in 2008, much higher than that found in comparative studies. Louse fly numbers declined throughout the swift breeding season. Parasite populations were heavily female biased, except for at the initial and final stages of the nestling period.     

Nesting Biology of Microstigmus thripoctenus Richards, with a Study on Nest Recognition (Hymenoptera: Crabronidae)

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.