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The invasive stink bug, Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae), is a serious pest of cole crops. Studies are underway to assess the potential of an exotic egg parasitoid from Pakistan, Ooencyrtus mirus Triapitsyn & Power (Hymenoptera: Encyrtidae), as a biological control agent for this pest. In the present study, the ovipositional preference of O. mirus reared for multiple generations on B. hilaris, Thyanta pallidovirens (Stal), or Nezara viridula (Linnaeus) (Hemiptera: Pentatomidae) for eggs of these three stink bug species was evaluated. The first host accepted for oviposition, the number of parasitoid eggs (as indicated by pedicels) laid on each host egg at different time intervals, and the number of wasps that emerged from parasitized eggs were recorded. Results show that O. mirus prefers eggs of its primary host, B. hilaris, for oviposition over the alternate hosts tested regardless of whether the parasitoids were reared on the primary or alternate hosts. The percent parasitism in the first 2 h of exposure also was higher on B. hilaris eggs although it was not significantly different from T. pallidovirens eggs for parasitoids reared on B. hilaris and N. viridula eggs. For all parasitoid populations, the mean number of emerged wasps per host egg ranged from 0.9 to 1.1 with no significant differences. Bagrada hilaris eggs were significantly smaller than T. pallidovirens and N. viridula eggs and female wasps that emerged from B. hilaris eggs had significantly shorter body length and head width than those that emerged from T. pallidovirens and N. viridula eggs.

This paper reviews the most important cases of trap crops and insectary plants in the order Brassicales. Most trap crops in the order Brassicales target insects that are specialist in plants belonging to this order, such as the diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), flea beetles, Phyllotreta spp. (Coleoptera: Chrysomelidae), and the pollen beetle, Meligethes aeneus Fabricius (Coleoptera: Nitidulidae). In most cases, the mode of action of these trap crops is the preferential attraction of the insect pest for the trap crop located next to the main crop. With one exception, these trap crops in the order Brassicales have been used with brassicaceous crops. Insectary plants in the order Brassicales attract a wide variety of natural enemies, but most studies report on their effect on aphidofagous hoverflies and parasitoids. The parasitoids benefiting from insectary plants in the order Brassicales target insects pests ranging from specialists, such as P. xylostella to highly polyfagous, such as the stink bugs Euschistus conspersus Uhler and Thyanta pallidovirens Stål (Hemiptera: Pentatomidae). The three most common trap crops in the order Brassicales are Indian mustard, Brassica juncea (L.) Czern, Chinese cabbage, Brassica rapa L., and yellow rocket, Barbarea vulgaris R. Br., while the three most common insectary plants are sweet alyssum, Lobularia maritima (L.) Desv., white mustard, Sinapis alba L, and B. vulgaris. Except for Tropaeolum majus L. (Tropaeolaceae), and Capparis decidua (Forssk.) Edgew. (Capparaceae), the tested trap crops and insectary plants in the order Brassicales belong to the family Brassicaceae.

Predatory wasps are one of the few natural enemies to attack late instar pentatomid nymphs and adults. However, there is a substantial lack of information about their flight and nesting behavior, making them poorly understood. We report 3 yr of observational data of Astata unicolor Say 1824 foraging behavior and phenology from a residential site in Portland, OR. A. unicolor attacked and paralyzed at least four hemipteran species, and 64% of paralyzed prey were from the invasive Halyomorpha halys (Stal; Hemiptera: Pentatomidae). Peak flight occurred between late July and mid-September. Though unmanaged and solitary, A. unicolor’s preference for H. halys demonstrates that native predators contribute to mortality and potentially management of economically important insects. This is one of the few studies to document predatory wasps’ potential for biological control of H. halys. Additional work on Astata is necessary to determine whether trap nesting, dispersal, or habitat enhancement, broadens the potential for expanded biological control.

Feeding behaviors of the redbanded stink bug, Piezodorus guildinii (Westwood), on vegetative (stem and leaflet) and reproductive (pod) tissues of soybean, Glycine max (L.), were recorded using an AC-DC electropenetrograph (EPG) apparatus. Eight different probing waveforms were characterized and defined: Pg1a, Pg1b, Pg1c, Pg1d, Pg2, Pg3a, Pg3b, and Pg4 grouped into three different families, P, I, and N. Histological studies of intact stylets within salivary sheaths observed during Pg1b, Pg1c, Pg2, and Pg3 waveforms were correlated with the specific penetration sites. Waveforms Pg1a, Pg1b, Pg1c, and Pg1d (pathway—family P) occurred at the start of probing activities and represent stylet penetration deep into plant tissue. Waveforms Pg2, Pg3a, and Pg3b (family I) represent the food ingestion phase. Pg2 waveform represents xylem sap ingestion primarily on leaves and stems. During Pg3a, stylets were moving, lacerating deeply into pod tissue and partially retracting; during Pg3b, stylets were motionless inside the pod tissue. Pg3b occurred interspersed with waveform Pg3a. Waveform Pg4 (family N) represented short interruptions that occurred within waveform Pg2. The study demonstrated that P. guildinii uses the cell rupture strategy to ingest from endosperm in soybean pod, and the same insect could switch to salivary sheath feeding to ingest from xylem in soybean leaves and stems. This unusual behavior explains symptoms of stink bug damage to soybean. The P. guildinii waveforms defined herein will allow future EPG studies to aid in development of soybean varieties that resist the feeding and damage caused by this and other stink bug pests.

Stink bugs (Hemiptera: Heteroptera: Pentatomidae) that occur in Minnesota wheat have received little attention. Due to the invasion of Halyomorpha halys (Stal) and the increasing abundance of native stink bugs in the region, a 2-yr statewide survey and 2-yr season-long survey were conducted to characterize the species composition, abundance, and seasonal dynamics of Pentatomidae in wheat. Surveys were performed using sweep-net sampling in wheat fields. Fourteen species of Pentatomidae (thirteen herbivorous and one predatory) were detected across both surveys. The recent invader, H. halys , was not collected in either survey. In the statewide survey, Euschistus variolarius (Palisot de Beauvois) was the most abundant species (63.08 and 75.33% of adults in 2011 and 2012, respectively) and the most prevalent species (collected from 10.53 and 51.54% of fields in 2011 and 2012, respectively). Species of intermediate abundance and prevalence were Euschistus servus euschistoides (Vollenhoven), Euschistus ictericus (L.), and Podisus maculiventris (Say). Across both years of the season-long survey, adults of herbivorous species first appeared in fields in early June followed by the appearance of herbivorous nymphs in early July. The abundance of nymphs peaked in late July to the beginning of August in 2013 and in early July in 2014. Adults were detected in fields throughout the season. The results presented here provide baseline information on the species composition, abundance, and seasonal dynamics of Pentatomidae in Minnesota wheat and will be necessary for documentation of changes to this fauna.

Trissolcus japonicus (Hymenoptera: Scelionidae) and Trissolcus plautiae are solitary endoparasitoids in eggs of stink bugs (Hemiptera: Pentatomidae). These two closely related parasitoids differ in their degree of host specificity. With the aid of scanning electron microscopy, we examined the external morphology, distribution, and abundance of the antennal sensilla of sexes of both species to gain insights into the olfactory mechanism in relation to host selection behavior. Seven types of sensilla were recorded in both species: basiconica, trichodea, grooved-peg, sickle-shaped, chaetica, papillary, and campaniformium sensilla. Sexual dimorphism of antennal structures occurred in both species. Male antennae possessed one more flagellomere and a larger number of olfactory sickle-shaped sensilla than female antennae, indicating that sensilla may be involved in mate or host location. There was a peg gland on the fifth antennomere of male antennae. Compared with males, females had a higher number of trichodea sensilla as well as papillary sensilla, which were not found in males. These sensilla might be involved in host recognition and acceptance during the drumming behavior of both species. No qualitative differences were recorded between the species in antennal structure, or sensilla types or topographical arrangement. However, the abundance of key sensilla was significantly different between species. T. plautiae females and males had larger numbers of trichodea sensilla than those of T. japonicus. T. japonicus females possessed fewer and larger sickle-shaped sensilla compared with T. plautiae females. These differences may provide a morphological basis for understanding the process of host habitat location and recognition in these parasitoids.

Hemiptera success can be partially attributed to their scent glands, which are dorsal abdominal glands (DAGs) in nymphs. Recent studies on Pentatomoidea have described cuticular modifications associated with DAGs, which compose the scent efferent system (SES), but the ontogeny has been poorly documented. We aim to—1) search for new SES characters in two representative species of Pentatomidae; 2) describe the SES ontogeny after hatching; and 3) compare the SES morphology between two species. Adults and immature samples from the first to fifth instars of Chinavia obstinata (Stal) (Pentatominae) and Cyrtocoris egeris Packauskas & Schaefer (Cyrtocorinae) were used as pentatomid representatives. SES structures were evaluated using scanning electron microscopy. Features that were never evaluated before are described: the scent efferent system orientation, periostiolar flap, periostiolar area, postostiolar projection, and peritreme lip. We observed remarkable differences between the first and second instars in both species, especially for DAGs 2 and 3; from the second to fifth instar, the modifications were subtle. Only the DAG1 scent efferent system persists in adults. The characteristics that present broader morphological diversity in the Pentatomomorpha are the following: peritreme, evaporatorium microsculpture, scent efferent system orientation, and peritreme lip. We conclude that any sample between the second and fifth instars can be used for species description and character extraction. We recommend using both traditional structures and the newly evaluated features in future descriptive and comparative studies for Pentatomomorpha.

The life history of the stink bug Mecidea minor Ruckes (Hemiptera: Heteroptera: Pentatomidae) was studied in the southern half of New Mexico from January 2005 to December 2007, and the egg and nymphal instars are described. This species was active year-round, occurring on various species of grasses but primarily on Lehmann lovegrass, Eragrostis lehmanniana Nees; grama grasses (Bouteloua spp.); Bermuda grass, Cynodon dactylon (L.); and tobosagrass, Pleuraphis mutica Buckley. Adults and late instars (fourth and fifth) were present during winter. The appearance and abundance of the eggs, nymphs, and adults during the year suggest this species is bivoltine with the possibility of a partial third generation. Instars can be distinguished by differences in morphological features, including body size and presence and relative development of wing pads.

Brontocoris tabidus (Signoret)and Supputius cincticeps (Stal) (Heteroptera: Pentatomidae) are natural enemies of lepidopteran defoliator pests. Therefore, more detailed information regarding the morphology of their eggs will certainly enhance the identification of these predators during the initial developmental stages for easy recognition of their presence in the field. In this study, eggshell morphology and morphometry of B. tabidus and S.cincticeps were examined. The diameter of the B. tabidus eggs was 2.03 ± 0.12 mm, height of 2.86 ± 0.08 mm, and the number of aero-micropylar processes were 14.8 ± 0.74; for eggs of the S.cincticeps, the diameter was 1.80 ± 0.32 mm, height 2.05 ± 0.27, and aero-micropylar processes 12.6 ± 1.18 mm. The eggs are oval to subglobose in shape, narrowing from the base to the apex; the operculum is circular convex with a circular array of aero-micropylar process on the anterior pole of the egg. The spicules seen on the flattened side of the B. tabidus and S.cincticeps eggs are fewer than those found in the operculum. Egg height and the number of aero-micropylar processes were higher in B. tabidus than in S.cincticeps. Such distinctive characters enable the identification of these predator's eggs.

Biological parameters of Podisus nigrispinus (Dallas) fed with third-instar Lepidoptera larvae of Spodoptera frugiperda J.E. Smith, Spodoptera cosmioides (Walker, 1858), and Anticarsiagemmatalis (Hübner, 1818), as well as eggs of Euschistus heros (F., 1798), the brown stink bug, were evaluated. Experiments were performed under controlled conditions (25 ± 1°C; 70 ± 10% relative humidity, and a photoperiod of 16:8 [L:D] h). P. nigrispinus had good nymphal development with >87% larval survival (viability), as well as high fecundity in adults, when fed with A. gemmatalis, S.frugiperda, and S. cosmioides larvae. Differently, adults of P. nigrispinus originating from nymphs fed with eggs of E. heros completed their life cycle; however, larval survival (viability) was reduced to 45.7%. Furthermore, these adults did not oviposit, and their body mass was from 50 to 73% lower than in individuals originating from nymphs fed with other tested prey. Taking into consideration that neither E. heros nor Spodoptera spp. are controlled by Bt soybean varieties expressing the Cry 1Ac protein, it can be assumed that the predator P. nigrispinus will still find prey species to feed in soybean fields even after the adoption of this pest control technology. This might help lower any potential negative impact of Bt soybean adoption above this insect predator. Moreover, the studied caterpillars proved to be potential prey for the predator's mass rearing, similarly to what is presently being done with coleopteran larvae.

The stink bug Bagrada hilaris (Bermeister) (Hemiptera: Heteroptera: Pentatomidae) is an Old World pest recently established in North America. Literature on the ovipositional behavior of B. hilaris is limited. As part of a study on the seasonal biology of B. hilaris in New Mexico, we included observations of the odd egg-laying behavior of this bug. Here, we describe and illustrate the phases associated with this behavior.

To effectively reduce agroforestry pest populations, two or more species of their natural predators, rather than only one, could be released. Podisus nigrispinus (Dallas) and Brontocoris tabidus (Signoret) (Heteroptera: Pentatomidae) are significant pest predators; however, these natural enemies can interact negatively, thereby decreasing the efficacy of biological control. The aim of this research was to study the effect of increasing the density of B. tabidus on the reproduction of P.nigrispinus and vice versa. The number of eggs per egg masses, nymphs, and longevity of P. nigrispinus decreased when the number of B. tabidus females increased. Furthermore, the egg viability was >75% with one, two, three, and four B. tabidus females; however, with five females, the viability of the P.nigrispinus eggs dropped below 70%. The number of egg masses of P. nigrispinus was similar with increasing density of B. tabidus and, even at low density, P. nigrispinus reduced reproduction of B.tabidus. P. nigrispinus and B. tabiclus often occur simultaneously in the field; these predators can coexist without any reproductive damage to any species when both are at low density.

“Integrative taxonomy” is a conceptual multisource approach in which the nomination of a species is considered as a hypothesis subject to evaluation through different empirical evidence. In this study, we followed a hypothesis-driven approach, where a set of specimens are used to test previous hypotheses about the existence of species. Thus, Oenopiella Bergroth is revised, based on morphology with emphasis on the genitalia of both sexes. Oenopiella unidentata Spinola, Oenopiellapunctaria Stål, and Oenopiella pallidula Stål are redescribed and illustrated, and two new species are described, Oenopiella ventanensis Grazia sp. nov. from Argentina and Oenopiella flonensis Fernández-Aldea sp. nov. from southern Brazil. A key to separate the species is provided. The reliability of O.punctaria and O. unidentata is evaluated through a reanalysis of their morphological characters, by exploring differences in qualitative and quantitative morphologic characteristics. All lines of evidence support these species hypotheses.

Animals must find and select mates in environments that naturally vary in both space and time. Of particular importance for many species are the availability and phenology of host plants for feeding and oviposition sites. Here, we used Murgantia histrionica (Hahn) (Hemiptera: Pentatomidae), a herbivorous insect, to determine mating preferences and success using mating assays and preferences based on odor cues.Wemanipulated the natal and encounter contexts using two different host plants, mustard and broccoli. We found that both the natal host plant and the host plant where insects encountered potential mates significantly affected mating success in this insect. Broccolireared individuals were more likely to mate in general; however, all individuals were more likely to mate when placed in an encounter context of mustard. Using a separate assay, we also found that the natal host plant affected female preference based on odor cues; females preferred the odors of males from the same natal environment that the females experienced as nymphs. In addition, we examined color and body size for host plant effects as both size and color are important factors for many species during mate choice. We found that individuals reared on mustard were larger than those reared on broccoli. However, the proportion of orange color on the dorsum of insects was not significantly affected by the natal host plant. In summary, these results suggest that changes in host plants, as commonly occurs seasonally, may have implications for sexual selection via mate choice.

In this study, we investigated the effect of egg rearing temperature and storage time on biological characteristics of the predatory stink bug Podisus nigrispinus (Dallas). In a preliminary experiment, eggs were incubated at 5, 10, 15, and 20°C to examine the effect of rearing temperature on egg development. From this, we found that 15°C was the optimal temperature for egg storage. To examine the effect of storage period on biological characteristics, eggs were stored at 15 ± 1°C for 0 (control), 1, 5, 9, 13, or 17 d, and then maintained at 25°C, allowing us to determine the effect of storage period on incubation period and egg viability. Once nymphs reached the second instar, they were kept in individual petri dishes, and we examined the effect of storage period on stadial length, nymphal viability, and weight of fifth-instar nymphs. Finally, when the nymphs reached the adult phase, we measured the effect of storage period on adult longevity, neonate adult weight, fecundity, and egg hatching success. Our results showed that the storage of eggs at 15 ± 1°C for periods of up to 17 d did not significantly affect most of the biological characteristics analyzed.

Feeding behavior can explain how predaceous Pentatomidae use different food sources as a result of ecological and evolutionary changes. This study describes the salivary glands of adults of the predator Supputius cincticeps (Stål) (Heteroptera: Pentatomidae) to assist in understand the feeding habits of this natural enemy. A pair of principal and accessory glands in the prothorax form the salivary system of S. cincticeps. The principal glands are bilobed with a spherical anterior lobe and are smaller than the posterior lobe, which has a prolonged sack form. The accessory glands are present in a long and tubular form that arises from the terminal portion of the curved accessory duct. The salivary system of S. cincticeps presents the same morphological pattern of other Asopinae predators.

Understanding the predation on pest insects through controlled feeding on their prey can provide insight into natural methods of pest control. The growth, survival, and development of the predatory stink bug (Podisus nigrispinus Dallas) fed on the eggs, larvae, and pupae of the diamondback moth, Plutella xylostella L, was examined in the laboratory. Second instar P.nigrispinus (12–24 h old) were fed various prey and monitored daily as they molted through nymphal stages and adulthood until death. The growth, survival, and egg production of stink bugs fed P.xylostella larvae and pupae were compared. P.xylostella eggs and first instars are inadequate food sources, whereas fourth instars and pupae can sustain the development of P.nigrispinus. Egg output of females was greater with pupae than with larvae. Male longevity was greater with larvae than with pupae. More P.xylostella larvae than pupae were consumed by P.nigrispinus. The high consumption rates of P.xylostella by P.nigrispinus in the laboratory indicate that this predatory stink bug may be a potential biological control agent for this pest.

ABSTBACT Biological invasions often have devastating impacts on ecosystems and economies, while facilitative interactions between invasive and native species are often overlooked. Here, we demonstrate how the invasive brown marmorated stink bug, Halyomotpha halys (Stål) (Hemiptera: Pentatomidae), facilitates native Hymenoptera by opening a novel feeding niche. In the invaded mid-Atlantic region of the United States, several species of native ants and wasps feed on wound exudates from stink bug feeding sites; these exudates have high sugar concentrations and are rapidly used by indigenous Hymenoptera. Positive facilitative interactions between invasive and keystone native species such as ants may have far reaching impacts on invaded ecosystems.

Stink bugs are economically important pests that damage a wide range of crops in the southeastern United States. Stink bug feeding on developing cotton (Gossypium hirsutum L. ) bolls may result in reduced yield and loss of fiber quality; similarly, feeding on developing soybean [Glycine max (L.) Merr.] pods can reduce yield and seed quality. During 2009 and 2010, the seasonal abundance and reproductive biology of Chinavia hilaris (Say) and Nezara viridula (L.) were investigated in replicated 1.62–2.83-ha farmscapes containing equal proportions of corn (Zea mays L.), cotton, peanut (Arachis hypogaea L.), and soybean. Crops were sampled weekly by using whole plant examinations in corn and sweep net sampling in cotton, peanut, and soybean. In 2010 only, adults were dissected to rate their reproductive development, and nymphs were classified to instar. No C. hilaris adults or nymphs ever were observed in corn; however, nymphs were observed in cotton and soybean during late September with peak abundance occurring just after the autumnal equinox. The peak of late-instar nymphs was followed within 2 wk by a peak of nonreproductive adults. More adults were observed in soybean than cotton. In contrast, N. viridula nymphs and adults were found across all crops and had multiple generations throughout the growing season. Results from this study indicate that C. hilaris and N. viridula are different in voltinism, phenology, and use of hosts. These data provide knowledge of stink bug biology and population ecology at the landscape level and are useful for designing and implementing stink bug management programs.

Male genitalia, including the pygophore, parameres, and inflated aedeagi, are compared between the midwestern species of Euschistus [i.e., E. ictericus (L.), E. politus Uhler, E. servus (Say) (including E. s. servus and E. s. euschistoides (Vollenhoven), E. tristigmus (Say) (including E. t. tristigmus and E. t. luridus Dallas), and E. variolarius (Palisot de Beauvois) ]. These structures differ markedly between these taxa with the exception of the two subspecies of E. servus and of E. tristigmus, thus confirming their subspecific status.

A phylogenetic analysis of 31 Oriental and Palaearctic genera of the tribe Halyini of South and Central Asia is presented here, concentrating upon the 22 genera for which complete data were available. Sixty-one morphological characters were analyzed using parsimony, including characters of the scent-gland apparatus and internal and external male and female genitalia. Using Phricodus as an outgroup, a single most-parsimonious tree resulted, following character reweighting according to their fit to the 52 multiple shortest trees initially found. Carenoplistus was always basal, and Jugalpada and Mustha were plesiomorphic in most bootstrapped trees. Two relatively plesiomorphic clades were identified, the Halys group (Salixocoris, Halys, and Neohalys) and the Paranevisanus group (Erthesina, Apodiphus, and Paranevisanus). Although strong bootstrap support existed for a clade of 12 genera (Tipulparra, Sarju, Izharocoris, Dalpada, Tachengia, Meridindia, Cahara, Ameridalpa, Eupaleopada, Meridalpa, Lodosocoris, and Neolodosocoris), the only consistent clades within it were a Dalpada group (Sarju, Izharocoris, Tachengia, and Dalpada) and a Lodosocoris group (Lodosocoris and Neolodosocoris). Tentative placements of the other nine genera are made, and a generic key is provided.

Stink bugs are economically important pests of food and fiber production throughout the southeastern United States. In cotton, stink bugs feed on developing bolls thereby decreasing yield and fiber quality. The brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), is a common species that is found throughout the southeast and feeds on a variety of wild and agronomic hosts. In this study, the population dynamics and reproductive biology of E. servus were assessed in 1.62–2.83-ha farmscapes planted with corn (Zea mays L.), cotton (Gossypium hirsutum L.), peanut (Arachis hypogaea L.), and soybean [Glycine max (L.) Merr.]. Farmscapes were sampled weekly using whole plant sampling for corn and sweep net sampling in cotton, peanut, and soybean. In 2010, but not 2009, nymphs were classified by instar, and adults were dissected to rate gonads as nonrepro-ductive, intermediate, or reproductive. Regardless of year, stink bugs observed in corn during the spring and early summer and were a mixture of all three reproductive stages. The number of E. servus nymphs and adults was low in all crops during the summer (July, August, and early September). In late September, the number of fifth instars rose sharply followed by an increase in the number of nonreproductive adults, which implies that these adults resulted from reproduction as opposed to immigration. Incidence of late instars and nonreproductive adults was extremely low for corn, cotton, and peanut, and these host plants did not seem to be highly suitable reproductive hosts. Results from this study are useful for pest management programs that focus on reducing stink bug populations on a landscape scale.

We describe a new species of stink bug, Murgantia thomasi (Hemiptera: Heteroptera: Pentatomidae), from the Dominican Republic. Diagnostic characters include both external anatomy and the male and female genitalia.

Effects of photoperiod on reproduction and longevity of Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) were assessed under seven different photophases (10, 11, 12, 13, 14, 15, and 16 h) at a constant 28 ± 1°C temperature and 70 ± 10% RH in the laboratory. Photoperiod affected the longevity of P.nigrispinus females. The highest longevity (24.10 d) occurred with a 15-h photoperiod, compared with longevity of 9.75 d at 12-h photoperiod. The preoviposition period of P.nigrispinus was influenced by the photoperiod. The preoviposition period of P.nigrispinus was longer for the 16-h photoperiod (7.25d) than for the 12- (4.06d), 13- (4.00 d), and 14-h (3.68d) photoperiod. The postoviposition period, the number of egg clutches per female per day, and the interval between egg clutches were not affected by the photoperiod. The postoviposition period ranged from 1.46 d (at 14 h of light) to 3.71 d (at 11 h of light). The number of egg clutches per female per day varied between 0.19 (at 11 h or 14 h of light) and 0.40 (at 15 h of light). The interval between egg clutches ranged from 1.29 d (at 14 h of light) to 2.07 d (at 11 h of light). The variation in the number of eggs and egg clutches per female of P.nigrispinus in relation to their age varied according to the photophase to which they were exposed. The fecundity of P.nigrispinus females was higher in 15 h of light. These informations serve as a valuable ecological variable in modeling population dynamics of P.nigripinus, both in the field and in the laboratory, thereby contributing to the success of A.argillacea control programs.

Host plant use by nymphs and adults of the nonnative species Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) was investigated proximal to the location of its introduction, Allentown, PA. The seasonality of H. halys in the United States had not been thoroughly studied before this work. It is reported to have ≈300 host plants in its native range that could make control and identification of small populations difficult. Weekly beat samples were conducted beginning at petal fall (mid-April) in Pyrus spp. until the first frost (mid-October) from 2005 to 2007 on a variety of ornamental trees, shrubs, and agricultural crops. Egg masses were first observed on Paulownia tomentosa Thunb. the first week of June. In 2006 and 2007, Fraxinus americana L. was an important mid- and late season host for adults. Nymphal abundance differed seasonally. P. tomentosa supported high densities during the early season, whereas Viburnum opulus variety americanum Aiton was the preferred mid-season host, and Viburnum prunifolium L. and Rosa rugosa Thunb. had the highest densities of nymphs during the late season. Abundance of nymphs was strongly associated with maturing fruit or pods. All plants surveyed supported populations of H. halys, suggesting a large host range. In late August, a large adult population peak was observed (850–1,000 degree days [DD]), shortly after the DD accumulation for development to imaginal eclosion, supporting hypotheses that H. halys is likely univoltine in this region. Relative to native pentatomid species, H. halys was by far the predominant species collected in samples on ornamental and cultivated crops.

The progress of embryonic development may be observed in eggs of the rice stink bug, Oebalus pugnax (F.) (Hemiptera: Pentatomidae), because obvious color or color pattern changes may be viewed through the transparent chorion. All viable egg masses of the rice stink bug progressed through similar color or color pattern changes at the six constant temperatures that ranged from 21.1 to 37.8°C. Whenever the length of time within a pattern was expressed as a percentage of the total developmental time, the proportion of time within a pattern was not influenced by changes in temperature. However, temperatures used in this study were within the linear range for total development and within each color pattern of the rice stink bug eggs described in this article. The upper lethal constant temperature was estimated to be 37.8°C. Although phases of blastokinesis could be viewed, most were not related to color patterns in this study, except the katatrepsis phase, which is pictorially described. Rice stink bug egg masses consisted of two rows, the eggs being in contact but those of one row alternate in position with the other row. Embryos in both rows were oriented with the ventral surface toward the center of the egg mass.

The southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), and other related species have become pests in cotton, Gossypium hirsutum L., after successful eradication efforts for the boll weevil. In Central Texas, little is known regarding the ecology of N. viridula. The reproductive status of N. viridula adults can be used to estimate population density and overwintering survival, but previous studies failed to provide clear visualizations for the developmental stages of the reproductive systems. This study was undertaken to provide improved visualizations of the developmental stages of the reproductive systems. Results will be critical in the accurate assessment of population reproductive status, estimation of population densities, and overwintering survival. Additionally, images presented here may be applicable to other stink bug species that infest row and fruit crops.

Brontocoris tabidus (Signoret) (Heteroptera: Pentatomidae) is an obligate zoophytophagous predator because its population can be maintained in the laboratory when fed on both prey and plants. We evaluated ultrastructural changes in the midgut digestive cells of adult B. tabidus, subjected to different treatments (starvation or feeding on plant material and prey) for different periods. Their midguts were dissected, divided into anterior, medium and posterior sections, processed, and analyzed with light and transmission electron microscopy. The anterior region of the midgut of B. tabidus, starved or fed on eucalyptus leaves, contained no glycogen. B. tabidus fed on plant material showed multivesicular bodies in this region, and spherocrystals after 6 h of feeding on prey. The microvilli of the medium midgut were longer than those of the anterior and posterior midgut. The posterior midgut differed from the other two regions by an abundance of mitochondria, rough endoplasmatic reticulum and double membrane vesicles in the apical region, 6 h after feeding. The ultrastructural features of the digestive cells in the anterior, medium and posterior regions of the midgut suggest that they play a role in digestive enzyme synthesis, ion and nutrient absorption, and storage and excretion of substances.

A new species of Trissolcus Ashmead (Hymenoptera: Scelionidae), Trissolcus halyomorphae Yang, sp. nov., is described from China. It is a solitary parasitoid in eggs of Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an economic pest that causes severe damage to pear, apple and other fruit and that also feeds on the leaves and stems of ornamental and forest trees. The new species is the principal natural enemy of the stink bug, with parasitism rates up to 70% and an average annual rate of 50%. Because of its high parasitism rates and other biological features, it has good potential as a biocontrol agent of the pest. Type specimens are deposited in Insect Museum, Chinese Academy of Forestry, Beijing, China.

Mating behaviors of the predaceous spined soldier bug, Podisus maculiventris (Say) (Pentatomidae: Asopinae), were observed, and vibrational signals used in intraspecific communication were recorded and analyzed. Only males produced vibrational signals, using three different vibrational modes: vibration of the abdomen, percussion with the front legs, or tremulation of the body. When recorded on a nonresonant substrate (a loudspeaker membrane), the mean dominant frequency of signals produced by abdominal vibration varied between 90 and 140 Hz, and of tremulatory signals between 8 and 22 Hz. Percussion signals were broad-band, with the dominant frequency ≈97 Hz and lower amplitude spectral peaks between 1,500 and 3,000 Hz. In the courtship phase of mating behavior, males emitted pulse trains composed of an abdominal vibration after a tremulatory pulse. Females stimulated by signals of abdominal vibration and composite signals expressed searching behavior and orientation toward the source of vibration, whereas no specific reaction to tremulatory signals was observed. Observations of mating behavior and playback experiments showed that the abdominal vibration signals had both long range calling and short range recognition functions. Tremulatory signals were emitted at close range and were essential for copulation to occur. The sequences of fast and repeated percussion signals were emitted both as individual signals during calling and courting or between vibratory and tremulatory pulses. However, unlike the other vibrational signals, percussion did not seem to be emitted in a particular behavioral context, and its possible function in eliciting responses from females is unclear.

The substrate-borne vibrational songs produced by phytophagous stink bugs of the genus Chlorochroa (Heteroptera: Pentatomidae) were recorded and compared. Sex- and species-specific vibrational songs were recorded from both sexes of three stink bug species of agricultural importance, the congeners Chlorochroa uhleri Stal, Chlorochroa sayi (Stal), and Chlorochroa ligata (Say). The temporal and spectral characteristics of the songs were determined, along with the context in which they were produced relative to contact between signalers and receivers. Vibrational communication started with production of the calling song by C. ligata females (FS-1), and by males of C. uhleri (male song [MS]-1) and C. sayi (MS-1). Males of all three species produced courtship songs (MS-2), whereas only C. ligata and C. sayi produced rivalry songs. Copulatory songs were produced by all three species, but they could not be attributed to either sex. Several of the songs share similarities in their fine-scale time units th...

Life history parameters and reproductive behaviors of the harlequin bug, Murgantia histrionica Hahn (Heteroptera: Pentatomidae), were determined. Total developmental time from egg to adult was48 d. After a sexual maturation period of7 d, both sexes mated repeatedly, with females laying multiple egg masses of 12 eggs at intervals of 3 d. Adult females lived an average of 41 d, whereas adult males lived an average of 25 d. Courtship and copulation activities peaked in the middle of the photophase. In mating experiments in which mixed sex pairs of virgin and previously mated bugs were combined in all possible combinations, the durations of courtship and copulation by virgin males were signiÞcantly longer with both virgin and previously mated females than the same behaviors for previously mated males. When given a choice between a virgin or previously mated female, previously mated males preferred to mate with virgin females, whereas virgin males showed no preference for virgin over previously mated females. Analyses of mating behaviors with ethograms and behavioral transition matrices suggested that a primary reason for failure to copulate by virgin males was the incorrect rotation of their pygophores to the copulation position, so that successful alignment of the genitalia could not occur.

In two previous articles, we reported that the male genitalia of six species of Parabrochymena and 14 species of Brochymena were distinct, particularly the shape and length of the vesica, thus supporting the establishment of Parabrochymena. Here, we present genitalic and nongenitalic information on four of the remaining five species of these two genera. Because of the results of these analyses, and in combination with similar analyses of species described earlier, we have transferred three of the four species [i.e., Parabrochymena enigmatica (Ruckes), Parabrochymena inbio Lariviere, and Parabrochymena poeyi (Guerin-Meneville)] to Brochymena. Also, we have provided descriptions of Brochymena and Parabrochymena and the New World tribe (Halyini), which includes only these genera.

Studies were conducted to test the suitability of absorbent cotton as an oviposition substrate for phytophagous stink bugs (Heteroptera: Pentatomidae). In confined boxes, >80% of total egg masses of Euschistus heros (F.), Dichelops melacanthus (Dallas), and Thyanta perditor (F.) were laid on cotton; for Piezodorus guildinii (Westwood) and Chinavia impicticornis (Stal), >60%. However, Nezara viridula (L.) and Edessa meditabunda (F.) did not oviposit on cotton balls, but instead on the box walls, on filter paper, or on food. Newly hatched nymphs successfully (>95%) left the eggshells despite the presence of cotton fibers around the egg masses.

Nezara viridula (L.) (Hemiptera: Pentatomidae), the southern green stink bug, has body color polymorphisms. N. viridula f. smaragdula is the common green morph, whereas the rare morph N. viridula f. aurantiaca is uniformly orange. Crossing studies were conducted to determine the inheritance of the orange body color trait. Mendelian genetic analysis suggested that orange body color is a simple, sex-linked recessive trait. In sperm precedence studies using orange females crossed with green and then orange males, or vice versa, the proportion of offspring attributable to the second male, P2, averaged 73.3% (extremes 23.5–100%). The average P2 in the first egg mass deposited after the new pairing was 71.8%. The pattern of sperm use provided evidence for incomplete sperm mixing, sperm stratification, and sperm displacement. Green females preferred mating with orange males (88%) compared with green males (12%), suggesting that disassortative mating may operate.

We present molecular data for an endosymbiont of the insect family Pentatomidae, located in the gastric caeca ofNezara viridula (L.) (Hemiptera: Pentatomidae) stink bugs. Restriction fragment length polymorphism and polymerase chain reaction analysis suggest that this bacterium is consistently present in caeca of N. viridula from a variety of geographic locations. The bacterium is present in different midgut sections in nymphs versus adults. The bacterium also was detected on eggshells after nymphs had hatched but not in ovarioles, suggesting oral rather than transovarial transmission. Surface sterilization of egg masses generated aposymbiotic insects. Aposymbiotic indi- viduals reached the adult stage, females laid viable eggs, and the offspring remained aposymbiotic in the following generation. No clear Þtness decrease was observed in aposymbiotic individuals over two generations. Phylogenetic analysis of a partial 16S rRNA data set with 21 Gammaproteobacteria suggested the inadequacy of neighbor-joining and maximum parsimony models to account for ho- moplasy apparent in a molecular data set, including a range of insect endosymbionts. Maximum likelihood-based analysis suggests that the N. viridula endosymbiont is closely related to a caeca- associated symbiont found in another stink bug family (Plataspidae). The high AT content of the symbiontOs 16S rRNA in relation to other insect endosymbionts, its location in the midgut of the host insect, oral transmission, and survival of aposymbiotic individuals suggest this symbiosis may be recently established.

Preferences of female predators for various species of prey may not correlate with nutritional value of the prey, notably with regard to resulting rates of reproduction in the female predator. This study assessed the biochemical status of adult female Podisus maculiventris (Say) as affected by prey species. Colony-reared females were fed one of five species of natural or factitious prey: beet armyworm, Spodoptera exigua (Hubner); fall armyworm, Spodoptera frugiperda (J.E. Smith); cabbage looper, Trichoplusia ni (Hubner); wax moth, Galleria mellonella (L.); or yellow mealworm, Tenebrio molitor (L.). Fresh weights and contents of lipid, protein, and yolk protein were compared over periods of 7, 15, and 22 d. Fresh weights and protein showed no significant differences by trial length or by prey species. Total lipid content was the most significant parameter in relation to time and species of prey, ranging from 5.3 to 15.5% of mean fresh weight. Female P. maculiventris varied significantly in total lipid content by prey species at 15 and 22 d, and by week only when fed fall armyworm. Highest lipid contents were observed in females fed yellow mealworm, and lowest lipid contents were observed in females fed cabbage looper and beet armyworm. Yolk protein content did not correlate with cumulative oviposition, but it did vary with time in those females fed on the beet armyworm or the wax moth. Lipid content in female predators may vary inversely with reproductive potential or egg load and offers a quantitative measure of food quality.

Laboratory studies with the southern green stink bug, Nezara viridula (L.), indicated the presence of bacteria Klebsiella pneumoniae (Schroeter) and Enterococcus faecalis (Andrewes & Horder) in the crop/stomach (ventriculus 1-3; V1-V3), and possibly Pantoea sp. in the gastric caeca (ventriculus 4; V4). Culturable bacteria were most abundant in V1-V3, and their abundance was drastically reduced in V4. The variable pH in the gut did not affect the presence of bacteria. Elimination of bacteria from the gut, by using the antibiotic kanamicin, did not affect nymphal developmental time or cause mortality, but it did cause reduced weight at adult emergence.

The diel periodicity of pheromone-mediated aggregations and mating and feeding cycles of Euschistus conspersus Uhler (Heteroptera: Pentatomidae) was investigated in a series of laboratory and Þeld experiments. The aggregation response of adult E.conspersus to lures loaded with the male-produced aggregation pheromone component methyl E2,Z4-decadienoate placed on com- mon mullein, Verbascum thapsus L., peaked in the early hours of the scotophase, at 2100 hours. Peak mating occurred at 2300 hours, with 78.5% of the insects in aggregations mating at this time. Aggre- gations dispersed and declined to 30% of their maximum level by dawn on pheromone-baited plants. Equal numbers of males and females were found within aggregations. Aggregations continued to form nightly and disperse by morning throughout a 72-h observation period on pheromone-baited and unbaited mullein plants. A laboratory analysis of feeding periodicity indicated that although feeding occurred throughout the 24-h observation period, the percentage of feeding insects was signiÞcantly higher during the scotophase. There were no differences between feeding rates of males and females. The implications of these Þndings for monitoring and management of E. conspersus are discussed.

Although new generation (prediapausing) adults of Dolycoris baccarum (L.) and Piezodorus lituratus (F.) (Heteroptera: Pentatomidae) spend the summer in fields, diapausing individuals spend the winter in overwintering localities under stones and plants. The phospholipid and triacylglycerol fatty acid composition of whole insects from prediapausing and diapausing adults was analyzed to determine changes in fatty acid unsaturation during diapause. The most abundant fatty acids from both fractions were palmitic (16:0), oleic (18:1), linoleic (18:2n-6), palmitoleic (16:1n-7), stearic (18:0), and linolenic (18:3n-3) acids. This represents a typical complement of heteropteran fatty acids. However, palmitoleic acid (16:1n-7) levels were higher in the triacylglycerol fraction in diapausing adults of P. lituratus (13.6%) than those reported from other heteropterans (1–3%) (Thompson 1973). The unsaturation/saturation ratio was significantly increased in triacylglycerol and phospholipid, apparently because of increases in major monounsaturated 18:1 at the expense of major saturated 16:0 during diapause. These changes were probably a response to low environmental temperatures.

In a previous article, we reported that the male genitalia of two species of Parabrochymena and four of Brochymena were distinct, particularly the shape and length of the vesica. Here, we present genitalic information on an additional four species of Parabrochymena and 10 species of Brochymena that further supports consistent differences between the two genera.