桉树枝瘿姬小蜂雄虫在中国的首次发现

本文用图文简要记述了桉树枝瘿姬小蜂雄虫的形态特征.这是该虫雄蜂在中国的首次报道.     

Rickettsia Symbionts Cause Parthenogenetic Reproduction in the Parasitoid Wasp Pnigalio soemius (Hymenoptera: Eulophidae)

Bacteria in the genus Rickettsia are intracellular symbionts of disparate groups of organisms. Some Rickettsia strains infect vertebrate animals and plants, where they cause diseases, but most strains are vertically inherited symbionts of invertebrates. In insects Rickettsia symbionts are known to have diverse effects on hosts ranging from influencing host fitness to manipulating reproduction. Here we provide evidence that a Rickettsia symbiont causes thelytokous parthenogenesis (in which mothers produce only daughters from unfertilized eggs) in a parasitoid wasp, Pnigalio soemius (Hymenoptera: Eulophidae). Feeding antibiotics to thelytokous female wasps resulted in production of progeny that were almost all males. Cloning and sequencing of a fragment of the 16S rRNA gene amplified with universal primers, diagnostic PCR screening of symbiont lineages associated with manipulation of reproduction, and fluorescence in situ hybridization (FISH) revealed that Rickettsia is always associated with thelytokous P. soemius and that no other bacteria that manipulate reproduction are present. Molecular analyses and FISH showed that Rickettsia is distributed in the reproductive tissues and is transovarially transmitted from mothers to offspring. Comparison of antibiotic-treated females and untreated females showed that infection had no cost. Phylogenetic analyses of 16S rRNA and gltA gene sequences placed the symbiont of P. soemius in the bellii group and indicated that there have been two separate origins of the parthenogenesis-inducing phenotype in the genus Rickettsia. A possible route for evolution of induction of parthenogenesis in the two distantly related Rickettsia lineages is discussed.The genus Rickettsia contains a group of obligate intracellular symbionts of eukaryotic cells and belongs to the family Rickettsiaceae in the order Rickettsiales of the Alphaproteobacteria (58, 90). Many species have medical importance as they are pathogens of humans and other vertebrates; pathogenic Rickettsia species infect their hosts through blood-feeding arthropods, including lice, fleas, ticks, and mites (51, 80). In addition to Rickettsia species that cause infectious diseases in vertebrates, symbiotic species have been found in disparate groups of organisms, including arthropods, annelids, amoebae, hydrozoa, and plants (53). Rickettsia appears to be especially common in arthropods, having been found in a wide range of taxa in the classes Entognatha (springtails), Insecta (booklice, lice, bugs, leafhoppers, aphids, whiteflies, fleas, flies, lacewings, moths, beetles, and wasps), and Acarina (ticks and mites) (86). However, in most cases, the effect of Rickettsia on the invertebrate host has not been established yet. In general, Rickettsia bacteria are facultative symbionts, but in the booklouse Liposcelis bostrychophila the association is strictly obligate and Rickettsia has an essential role in oocyte development (54, 92). Facultative symbiotic Rickettsia strains have been reported to negatively affect some aspects of host fitness, causing reductions in body weight, fecundity, and longevity in the pea aphid (16, 60, 64), reductions in viability in some blood-feeding arthropod vectors (5, 46), and increased susceptibility to insecticides in the sweet potato whitefly (41). There is also evidence that Rickettsia has positive effects on host fitness, such as a larger body size in infected leeches (40) and a possible role in the oogenesis of a bark beetle (93). Finally, facultative symbiotic rickettsiae can be reproductive parasites of insects. Rickettsia strains are the causal agents of male killing (infected male embryos die) in some ladybird (79, 88) and buprestid leaf-mining (42) beetles. They are also the cause of thelytokous parthenogenesis (in which mothers produce only daughters from unfertilized eggs) in a parasitoid wasp (32). Both kinds of reproductive manipulation bias the host sex ratio toward females and favor the spread of the transovarially inherited Rickettsia strains in the infected populations. In general, Rickettsia is transmitted primarily vertically to host progeny, but in pathogenic species there is concomitant horizontal transmission via intermediate vertebrate hosts, which plays an important role in maintaining the infection in populations of blood-feeding arthropods (53, 57). An exception is Rickettsia prowazekii, the epidemic typhus agent, which spreads only via horizontal transmission in louse host populations (5). Only one Rickettsia is known to be a plant pathogen, and leafhoppers transfer this pathogen horizontally between plants (20). The fact that Rickettsia can be transmitted horizontally and then perpetuated vertically in host descendants has probably been one of the most important factors determining the enormous diversity of Rickettsia symbiotic associations. This point has been emphasized by analyses that have revealed considerable incongruence between Rickettsia and host phylogenies, indicating that horizontal transfer has occurred multiple times over evolutionary timescales (53, 54, 86).In addition to Rickettsia, diverse heritable bacteria are known to manipulate host reproduction to enhance their transmission in arthropods (12, 23). Wolbachia (order Rickettsiales, family Anaplasmataceae), a close relative of Rickettsia (90), is able to induce all known forms of manipulation of reproduction, including cytoplasmic incompatibility, feminization of genetic males, male killing, and parthenogenesis (68). Previously, only Cardinium (Sphingobacteria) has been shown to cause a similar range of reproductive phenotypes, except for male killing (35). The emerging diversity of Rickettsia associated with arthropods (53, 86), combined with evidence that it can manipulate host reproduction in more than one way, suggests that this symbiont may also be a master manipulator.In the Hymenoptera, the dominant mode of reproduction is arrhenotoky; that is, diploid females develop from fertilized eggs, and haploid males develop from unfertilized eggs (76). However, thelytokous parthenogenesis is common, and in some lineages, like the superfamilies Chalcidoidea and Cynipoidea, it is strongly associated with Wolbachia or Cardinium infection (33, 35). Parthenogenesis-inducing (PI) bacteria cause restoration of diploidy in unfertilized haploid eggs, which results in female offspring (28, 50, 69). PI Wolbachia and PI Cardinium also occur in other groups of haplodiploid arthropods, such as mites (82), scale insects (56), and thrips (4). Previously, the only example of PI caused by Rickettsia was found in the eulophid parasitoid wasp Neochrysocharis formosa (1, 32). Besides PI bacteria, uniparental (thelytokous) reproduction in haplodiploid arthropods can also be caused by feminizing bacteria that are able to interact with the host sex determination system and force the development of genotypic males toward functional phenotypic females. To date, only Cardinium has been reported to be a causal agent of feminization in haplodiploid arthropods, and only two examples are known: a mite in which Cardinium causes haploid male embryos to develop as haploid females (18, 83) and a parasitoid wasp in which diploid males are converted to females (27).In this paper, thelytokous reproduction in a parasitoid wasp, Pnigalio soemius (Hymenoptera: Eulophidae), was studied. This wasp, which is probably a complex of cryptic species (8), is a solitary ectoparasitoid that attacks larvae of many leafminer insect species in the orders Coleoptera, Diptera, Hymenoptera, and Lepidoptera (48), some of which are pests of agricultural crops (37, 61). Female P. soemius wasps paralyze host larvae by injection of venom and subsequently lay a single egg next to the host inside a leaf mine; then the parasitoid larva eats the killed host (7). Commonly, P. soemius reproduces biparentally, and the occurrence of thelytoky has not been reported previously. The aims of this study were to determine whether symbiotic bacteria are involved in manipulating the reproduction of P. soemius and then to determine the taxonomic affiliation and phenotype of the manipulators of reproduction discovered. By using antibiotic treatments and karyological analysis of the insect studied, molecular and phylogenetic characterization of the symbiotic bacteria, and detection of intracellular symbionts by means of fluorescence in situ hybridization, it was demonstrated that a PI Rickettsia causes thelytokous reproduction in P. soemius.     

No Concordant Phylogeographies of the Rose Gall Wasp Diplolepis rosae (Hymenoptera,Cynipidae) and Two Associated Parasitoids across Europe

According to the Host-tracking Hypothesis, species of higher trophic levels with a close relationship to their hosts, such as parasites or parasitoids, are expected to show spatio-temporal phylogeographic patterns similar to those of their host. Alternatively, with ecological sorting, a subset of the local species pools might shift to a related host species, thereby disengaging common phylogeographic patterns. Here, we compare the phylogeographic structures of the cynipid rose gall wasp Diplolepis rosae across Europe and of two of its most common parasitoids, the wasps Orthopelma mediator and Glyphomerus stigma, by analysing the sequences of two gene fragments (COI and ITS 2). The phylogeographic structures of the three species associated with roses were incongruent. D. rosae had the lowest genetic diversity with one major clade, O. mediator showed the classical phylogeographic structure for Europe with one eastern and one western clade, and G. stigma had the highest diversity but no geographical structuring. This discordance of geographical patterns may be explained by 1) the dispersal propensity of adult parasitoids or 2) the parasitoids having the ability to switch to another host, while the primary host becomes rare or is even not available. Furthermore there was no indication that phylogenetic patterns were affected by Wolbachia infections. Our results document that communities of closely interacting species may be the result of idiosyncratic biogeographic histories.     

First record of Closterocerus chamaeleon,parasitoid of the Eucalyptus Gall Wasp Ophelimus maskelli (Hymenoptera,Chalcidoidea, Eulophidae), in the New World

The uniparental parasitoid Closteroceruschamaeleon (Girault) is discovered to be fortuitously present on a population of the invasive Eucalyptus Gall Wasp Ophelimusmaskelli (Ashmead) in Riverside, California. This is the first report from the New World of Closteroceruschamaeleon, which has proven to be a highly effective natural enemy of Ophelimusmaskelli in the Mediterranean Basin. The taxonomy and identification of Closteroceruschamaeleon is discussed.     

The British species of Achrysocharoides (Hymenoptera, Eulophidae)

Abstract. Taxonomic notes and a key are provided for the eleven species of Achrysocharoides found in Britain including A.carpini sp.n. Several forms of undetermined specific status are also described. Two species-groups are erected: the latreillii group and the aty s group. All British species have been reared as parasites only of leaf-mining larval Gracillariidae (Lepidoptera); one brood is here recorded from Caloptilia on Quercus; all other rearings are from Phyllono-rycter species. Parasite—host associations and speciation within the genus are discussed.     

麦氏安瘿蜂体内侵染Wolbachia的WO噬菌体的检测及其orf7基因序列分析

Wolbachia为节肢动物等的细胞质共生细菌,能对宿主的繁殖模式进行调控,包括诱导胞质不亲和、孤雌生殖、雌性化及雄性致死。WO噬菌体是一类侵染节肢动物体内Wolbachia的细菌病毒。为检测麦氏安瘿蜂Wolbachia是否被WO噬菌体侵染,本研究使用WO噬菌体的orf 7基因引物,对信阳、六安及长沙3种群的WO噬菌体进行了PCR检测。结果显示,3种群的雌、雄虫体内的Wolbachia均有WO噬菌体的侵染,感染率为100%。获得的3种群麦氏安瘿蜂Wolbachia的WO噬菌体orf 7基因序列均为371 bp,序列完全一致。其序列与粉斑螟Ephestia cautella的wECau B3-1和wCauA5-1株系、反颚茧蜂Asobara tabida的wAtabA3-3株系的一致性最高,在NJ和ML系统树中,均聚合在同一分支,属于WO噬菌体的第Ⅲ大群。     

Interrelationship between the raspberry cane midge, Resseliella theobaldi (Diptera: Cecidomyiidae) and its parasitoid, Aprostocetus epicharmus (Hymenoptera: Eulophidae)

The raspberry cane midge Resseliella theobaldi (Barnes) is one of the most important pests of cultivated red raspberry Rubus idaeus L. throughout Europe. For the last 50 years several studies have been made on the biology, life cycle and control of the pest. Some data can also be found on its natural enemies, but among these species only the chalcidoid Tetrastichus inunctus Nees turned out to be important in controlling raspberry cane midge populations. However, this species name is now ambiguous as the type is lost. In the present study, Aprostocetus epicharmus Walker was the chalcidoid species that parasitized the larvae of the raspberry cane midge, and its biology seems to be very similar to that of T. inunctus. It is therefore probable that the eulophid species earlier referred to as T. inunctus in the literature is A. epicharmus. Besides discussing this problem, particular consideration and detailed data are given on the biology and life cycle of A. epicharmus in relation to R. theobaldi. Different factors having effect on the population dynamics of both species are also discussed as results of a survey on several red raspberry cultivars, carried out in Hungary between 2002 and 2005.     

Phyllonorycter medicaginella (Lepidoptera, Gracillariidae) and its parasitoids (Hymenoptera, Eulophidae) in the Middle Volga River basin

Fifteen species of parasitoids, Chrysocharis idyia (Walker, 1983), Ch. laricinellae (Ratzeburg, 1848), Ch. submutica Graham, 1963, Ch. viridis (Nees, 1834), Hemiptarsenus ornatus (Nees, 1834), Neochrysocharis formosa (Westwood, 1833), Pediobius cassidae Erd?s, 1958, P. metallicus (Nees, 1834), Pnigalio nemati (Westwood, 1838), P. mediterraneus Ferriére & Delucchi, 1957, P. pectinicornis (Linnaeus, 1758), P. soemius (Walker, 1839), Rhicnopelte crassicornis (Nees, 1834), Sympiesis gordius (Walker, 1839), and Hyssopus sp. n., were reared from Phyllonorycter medicaginella on Melilotius offlcinalis for the first time. Hyssopus simbirskiensis sp. n. reared from Ph. medicaginella is described. Eight ectoparasitoid species (Hyssopus ornatus, H. simbirskiensis sp. n., Rh. crassicornis, P. mediterraneus, P. nemati, P. pectinicornis, P. soemius, and S. gordius) attack all the larval instars of Ph. medicaginella. Seven endoparasitoids (P. cassidae, P. metallicus, Ch. idyia, Ch. laricinellae, Ch. submutica, Ch. viridis, and N. formosa) attack only the 4-5th-instar larvae.     

Evolution of the courtship display of Melittobia (Hymenoptera: Eulophidae)

Melittobia, a polyphagous pupal parasitoid of many solitary bees and wasps, has a complex courtship display, the evolutionary history of which is poorly understood. The current phylogeny of this genus suggests the complexity of the courtship has increased over time. We test this hypothesis using Bayesian and Maximum likelihood techniques to construct a molecular phylogeny of Melittobia-the first for this genus using modern techniques--using two intergenic regions (Internal Transcribed Spacer regions 1 and 2) and Cytochrome Oxidase 1 (CO1), and reconstruct the ancestral state of each major node in the phylogeny for five behaviors coincidental to major shifts in display complexity. We show that species-groups identified solely on behavioral characters are reliable, although the relationships among groups are different than those previously hypothesized. We also show that behaviors traditionally used in the courtship studies do not support a hypothesis of increasing display complexity over time.     

Oviposition behavior of Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) on its natural host

Phymastichus coffea LaSalle is an African endoparasitoid of adults of the coffee berry borer, Hypothenemus hampei (Ferrari) that was introduced into Mexico for biological control purposes. The objective of this study was to investigate the oviposition behavior of P. coffea on its host under laboratory conditions. The results indicate that P. coffea females exhibited 12 behavioral acts during and after oviposition, such as, walking, cleaning, flying, surface landing, resting, host landing, host antennation, touching the host with forelegs, host recognition, walking on the host, oviposition and cleaning after oviposition. The sequence of each behavior is described in an ethogram.     

中国宽脉啮小蜂属(膜翅目:姬小蜂科)的种类及鉴定

本研究对我国姬小蜂科Eulophidae宽脉啮小蜂属Dzhanokmenia Kostjukov,1977进行分类和比较形态学研究,记录该属7种,其中中国新记录2种,提供了7种的鉴别特征及生物学和地理分布信息。比较形态学研究结果表明:宽脉啮小蜂属在头部、触角、腹部背板、腿节以及雌性外生殖器着生位置等结构上存在明显的形态特化和种间差异,这些结构特征能有效应用于属内物种鉴定,为该类群物种的准确鉴定提供依据。基于上述研究结果,本研究编制了该属的分种检索表。     

冈崎姬小蜂生物学特性研究

通过对福州城郊田间周年调查,发现在美洲斑潜蝇（Ｌｉｒｉｏｍｙｚａ ｓａｔｉｖａｅ Ｂｌａｎｃｈａｒｄ）寄生性天敌中,冈崎姬小蜂（Ｎｅｏｃｈｒｙｓｏｃｈａｒｉｓ ｏｋａｚａｋｉｉ Ｋａｍｉｊｏ）是主要优势种。本对冈崎姬小蜂的生物学特性进行了研究,包括交配、取食、寄生、羽化、趋性、性比、越冬、不同营养条件及不同光照时数对成蜂寿命的影响,以及各虫态历期。     

Genetic Variation in Behavioral Response to Herbivore-Infested Plants in the Parasitic Wasp, Cotesia glomerata (L.) (Hymenoptera: Braconidae)

Female Cotesia glomerata (L.) relies on stimuli from herbivore-infested plants to select suitable hosts, but behavioral response to such stimuli is highly variable among individuals. This study investigates a genetic component of phenotypic variability in both short-range host-search and long-range host-location behaviors in the tritrophic system consisting of cabbage plants (Brassica oleracea L.), cabbage butterfly (Pieris brassicae L.) and the parasitoid, by comparing full-sib families established from a laboratory population and isofemale strains from a field population. Short-range host-search behaviors were examined within a Petri-dish test arena, and long-range host-location behaviors assessed in a wind tunnel. Significant differences among full-sib families were shown in the duration of walking on a plant-herbivore complex (i.e., a leaf section with two host caterpillars, their silk and feces) and searching off the complex, and the total time elapsed for wasps to locate a host larva after release into the test arena. Flight responses to and landing choices between the intact and the herbivore-infested plants were also significantly different among these families. Effects of families on both short-range host-search and long-range host-location behaviors were consistent, without significant influences of host larvae from which wasps emerged. The analysis of isofemale strains reveals that strains account for significant variation in the oriented flight response to herbivore-infested plants, and the isofemale heritability for this behavioral character is estimated as 0.447. The results suggest that genetic variation exists at different behavioral levels of the host-selection process in this parasitoid.     

Record of Diglyphus walker (Hymenoptera: Eulophidae) species in Brazil

Leafminers (Diptera: Agromyzidae) are pests of various crops, mainly in greenhouses, and have Diglyphus spp. as important leafminer larval parasitoids. Until recently, only Diglyphus insularis (Gahan) had been reported in Brazil. In here we report the first records of Diglyphus begini (Ashmead), D. intermedius (Girault) and D. isaea (Walker) in Brazil. These parasitoids were found parasitizing leafminer larvae on cultivated and spontaneous plants in some areas of Minas Gerais state, Brazil.     

Ultrastructure of the antennal sensilla of the cockroach-egg parasitoid,Tetrastichus hagenowii (Hymenoptera: Eulophidae)

Eggs of a number of cockroach species are parasitized by Tetrastichus hagenowii. The ultrastructure of the sensilla on the antennae of females and males was examined by scanning and transmission electron microscopy. The females have two types of multiporous plate sensilla while the males have only one. Type 1 is found in females and males and has a relatively thin cuticular wall and many pores, while type 2 is found only in females and has a relatively thick cuticular wall and few pores. Both sexes have nonporous, thick-walled, socketed hairs; multiporous, nonsocketed hairs; multiporous, thick-walled pegs; and terminal hairs. In addition, males have multiporous, nonsocketed, long hairs. The sensilla are similar, in many respects, to the sensilla of other chalcid parasitoids. The antennal sensilla of female T. hagenowii are probably involved in ovipositional behavior. The multiporous, long hairs of the male possibly receive stimuli during mating behavior A chemoreceptive function is proposed for the multiporous plate sensilla.