Showing papers in "Annals of The Entomological Society of America in 2013"
TL;DR: This work sequenced one mitochondrial and two nuclear genes from 73 specimens belonging to 19 species to construct phylogenies and examine species relationships and limits within the genus Bactrocera and several species of the B. dorsalis complex-specifically addressing the placement of B. invadens.
Abstract: The genus Bactrocera (Tephritidae) contains >500 species, including many severe pests of fruits and vegetables. Although native to tropical and subtropical areas of Africa, India, Southeast Asia, and Australasia, a number of the pest species, largely members of the Bactrocera dorsalis (Hendel) complex, have become widespread through accidental introduction associated with agricultural trade. The B. dorsalis complex includes several morphologically and ecologically similar pests, making species designations uncertain. One of these, Bactrocera invadens Drew, Tsuruta, and White, endemic to Sri Lanka, has spread across Africa in the last decade and become a major agricultural pest. We sequenced one mitochondrial and two nuclear genes from 73 specimens, belonging to 19 species to construct phylogenies and examine species relationships and limits within the genus Bactrocera and several species of the B. dorsalis complex-specifically addressing the placement of B. invadens. Results indicate the B. dorsa...
55 citations
TL;DR: These changes observed on activity of antioxidant enzymes, energy reserves, MDA content, and accumulation levels of Cd can be used as a reliable biomarker of environmental heavy metal pollution in model insect G. mellonella.
Abstract: In this study, we analyzed the effects of cadmium (125, 25, 5, 10, 20, and 40 mg per 100 g of nutrient) on total protein, lipid, and glycogen levels, lipid peroxidation (MDA), superoxide dismutase (SOD) and catalase (CAT) activities, and metal accumulation in Galleria mellonella L High concentrations of Cd (20 and 40 mg) significantly lowered total protein, lipid, and glycogen levels MDA level significantly increased when the nutrient contained 5 mg and more of Cd, whereas SOD activity significantly increased at Cd concentrations starting from 125 mg CAT activity significantly decreased at all concentrations Metal accumulation also significantly increased in a dose-dependent manner These changes observed on activity of antioxidant enzymes, energy reserves, MDA content, and accumulation levels of Cd can be used as a reliable biomarker of environmental heavy metal pollution in model insect G mellonella
46 citations
TL;DR: Temperature showed a profound effect on female longevity over this viable range of temperatures, as it decreased from 123.06 d at 17°C to 33.53 d at 30°C.
Abstract: The effect of temperature on the development, survival, longevity, and fecundity of the 14-spotted ladybird beetle, Propylea quatuordecimpunctata L. (Coleoptera: Coccinellidae) reared on bean aphid, Aphis fabae Scopoli (Hemiptera: Aphididae) was determined at six constant temperatures (17, 20, 25, 30, 32.5, and 35 ± 1°C) in the laboratory. Results showed a temperature—dependent development of the coccinellid. An appropriate linear model indicated that 218.0 degree days above a threshold of 10.2°C were needed to complete immature development from egg to adult emergence. Data were fitted to the nonlinear Briere model, which for total immature period estimated the upper developmental threshold at 36.0°C, the lower threshold at 12.2°C and the temperature for maximum developmental rate at 30.3°C. Survival of immature stages varied significantly across temperatures with the lowest survival of just 14% occurring at 32.5°C and the highest (96%) at 25°C. In addition temperature showed a profound effect on...
39 citations
TL;DR: The substantial intraspecific variation in the cocoon webs, especially those of A. tibialis, emphasizes the apparent difficulty of precise host manipulation by these wasps.
Abstract: The wasps Acrotaphus tibialis (Cameron), Eruga ca. gutfreundi Gauld, and Hymenoepimecis tedfordi Gauld induce their host spiders to spin modified “cocoon” webs just before they kill them and pupate. The cocoon webs induced by all three wasp species appear better designed to support and protect the wasps' pupal cocoons than are the normal orbs of their hosts. The typical cocoon webs induced by A. tibialis were similar to the protected resting webs built by their host spiders Argiope trifasciata (Forskal) but had more elaborate protective barrier tangles. The other two species of wasp induced the same host spider, Leucauge mariana (Keyserling) to build quite different cocoon webs. The cocoon webs of H. tedfordi varied somewhat, but usually included radial lines and a tangle below. They resembled the resting webs of the host in having a planar radial organization and (often) a tangle below, but lacked a hub and had their lines that were apparently composed of high numbers of individual strands. The three dimensional, radially arranged cocoon web of E. ca. gutfreundi had no clear counterpart in the webs of unparasitized L. mariana. The substantial intraspecific variation in the cocoon webs, especially those of A. tibialis, emphasizes the apparent difficulty of precise host manipulation by these wasps.
38 citations
TL;DR: It was concluded that an input impedance of 107 &OHgr;, with either DC or AC applied voltage, is optimal to detect all resistanceand electromotive force-component waveforms produced during chinch bug probing.
Abstract: Electrical penetration graph (EPG) monitoring has been used extensively to elucidate mechanisms of resistance in plants to insect herbivores with piercing-sucking mouthparts. Charac- terization of waveforms produced by insects during stylet probing is essential to the application of this technology. In the studies described herein, a four-channel Backus and Bennett ACÐDC monitor was used to characterize EPG waveforms produced by adults of two economically important chinch bug species: southern chinch bug, Blissus insularis Barber, feeding on St. Augustinegrass, and western chinch bug, Blissus occiduus Barber, feeding on buffalograss. This is only the third time a heteropteran species has been recorded by using EPG; it is also the Þrst recording of adult heteropterans, and the Þrst of Blissidae. Probing of chinch bugs was recorded with either AC or DC applied voltage, no applied voltage, or voltage switched between AC and DC mid-recording, at input impedances ranging from 10 6 to 10 10 , plus 10 13 , to develop a waveform library. Waveforms exhibited by western and southern chinch bugs were similar, and both showed long periods of putative pathway and ingestion phases (typical of salivary sheath feeders) interspersed with shorter phases, termed transitional J wave and interruption. The J wave is suspected to be an X wave, that is, in EPG parlance, a stereotypical transition waveform that marks contact with a preferred ingestion tissue. The sexibility of using multiple input impedances with the ACÐDC monitor was valuable for determining the electrical origin (resistance vs. electromotive force components) of the chinch bug waveforms. It was concluded that an input impedance of 10 7 , with either DC or AC applied voltage, is optimal to detect all resistance- and electromotive force-component waveforms produced during chinch bug probing. Knowledge of electrical origins suggested hypothesized biological meanings of the waveforms, before time-intensive future correlation experiments by using histology, microscopy, and other techniques.
35 citations
TL;DR: There is significant evidence suggesting that the presence of bacteria in or on the corpse seems to aid in larval development and pupariation, with bacteria either being used as a food source themselves or making nutrients more available to larvae.
Abstract: Animal remains represent ephemeral resources that provide nutrients to a wide range of organisms. On death, vertebrate carrion is immediately colonized with a variety of microorganisms (typically obligate or facultatively anaerobic bacteria from the air, from insects, or from the corpse itself), which produce odors through the breakdown of tissues, the alteration of volatile chemicals present in the environment, or both. Within minutes, certain necrophagous flies are attracted by these chemical signals, resulting in waves of oviposition and larviposition activity. Although there are certainly detrimental (pathogenic) bacteria in the milieu, there is significant evidence suggesting that the presence of bacteria in or on the corpse seems to aid in larval development and pupariation. This may be because of a change in larval nutrition, with the bacteria either being used as a food source themselves or making nutrients more available to larvae. Maggots also produce and secrete or excrete antimicrobia...
34 citations
TL;DR: The aphidiines presented in this work have been identified from 40 aphid taxa and two hundred sixty-six aphidiine— aphid—plant associations are presented, out of which 126 are new.
Abstract: Original information on aphidiines parasitizing aphids on herbaceous and shrubby ornamental plants in southeastern Europe is presented. In total, 22 species are keyed and illustrated with scanning electron micrographs, stereomicroscope micrographs, and line drawings. The aphidiines presented in this work have been identified from 40 aphid taxa. Two hundred sixty-six aphidiine— aphid—plant associations are presented, out of which 126 are new. The results are discussed in relation to the overall parasitoid—aphid-plant associations in the area.
32 citations
TL;DR: It is demonstrated how the invasive brown marmorated stink bug, Halyomotpha halys (Stål) (Hemiptera: Pentatomidae), facilitates native Hymenoptera by opening a novel feeding niche.
Abstract: 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 (Stal) (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.
32 citations
TL;DR: A study of male and female responses to playbacks of recorded and synthetic mimics of different vibrational signals on citrus plants was conducted to better understand the range of signals to which D. citri respond and potentially to co-opt or disrupt their vibrational communication.
Abstract: Mate-seeking in Diaphorina citri Kuwayama, a vector of the economically damaging huanglongbing citrus disease, typically includes male—female duetting behaviors. First, the male calls by beating his wings at ≈170–250 Hz, producing vibrations that are transmitted along the host tree branches to the female. If receptive, she immediately replies, helping to direct the searching male toward her. The duetting and searching continues until the male locates the female. Males and females are similar in size and produce wingbeat vibrations with similar temporal and spectral patterns. A study of male and female responses to playbacks of recorded and synthetic mimics of different vibrational signals on citrus plants was conducted to better understand the range of signals to which D. citri respond and potentially to co-opt or disrupt their vibrational communication. In general, both sexes responded well to a variety of 0.3–0.5-s signals that included multiple harmonics of ≈200-Hz wingbeatfrequency chirps up ...
32 citations
TL;DR: Half (7) of the 14 most common mites collected in this study showed a marked preference for a single host species, which contradicts the hypothesis that nonparasitic mites are typically not host specific, at least locally.
Abstract: Mites (Arachnida: Acari) are one of the most diverse groups of organisms associated with bark beetles (Curculionidae: Scolytinae), but their taxonomy and ecology are poorly understood, including in Canada. Here we address this by describing the diversity, species composition, and host associations of mesostigmatic and oribatid mites collected from scolytines across four sites in eastern Ontario, Canada, in 2008 and 2009. Using Lindgren funnel traps baited with α-pinene, ethanol lures, or Ips pini (Say) pheromone lures, a total of 5,635 bark beetles (30 species) were collected, and 16.4% of these beetles had at least one mite. From these beetles, a total of 2,424 mites representing 33 species from seven families were collected. The majority of mite species had a narrow host range from one (33.3%) or two (36.4%) host species, and fewer species had a host range of three or more hosts (30.3%). This study represents the first broad investigation of the acarofauna of scolytines in Canada, and we expand...
29 citations
TL;DR: Two new cryptic species within the P. abjectum group are described based on the differences determined in mitochondrial sequences and in the shape of the wing, which are related to the stigma shape and the position of the radial nerve.
Abstract: The genus Praon represents a large group of aphid endoparasitoids and is exemplary for the problems encountered in their taxonomy because of a great variability of morphological characters. To investigate the intraspecific variability and to ascertain cryptic speciation within the Praon abjectum Haliday group, biotypes in association with the aphid hosts Aphis sambuci L., Longicaudus trirhodus Walker, and Rhopabsiphum spp. were examined. We combined molecular and geometric morphometric analyses, that is, partial sequences of the mitochondrial cytochrome oxidase subunit I and nuclear 28SD2 genes and the shape of the forewing. Low variation of 28SD2 sequences confirmed the close relatedness of species from the genus Praon. Analysis of the cytochrome oxidase subunit I sequences however identified three separate taxa within the P. abjectum group with substantial genetic divergence. The biotype of P. abjectum associated with L. trirhodus differed from those associated with Rhopabsiphum sp. and A. samb...
TL;DR: The distribution of R. pomonella is documented through the Pacific Northwest and Rocky Mountain states of the western United States to help clarify the origin (s) of the fly outside the eastern United States and discuss the evolutionary and applied implications of the results.
Abstract: ABSTBACT The apple maggot fly, Rhagoletis pomonella Walsh (Diptera: Tephritidae), is a major pest of commercially grown domesticated apple (Malus domestica Borkhausen) in North America. The shift of the fly from its native host hawthorn (Crataegus mollis) to apple in the eastern United States is often cited as an example of incipient sympatric speciation in action. However, R. pomonella is also present in the Pacific Northwest region of the United States where it infests apple, native black hawthorn (Crataegus douglasii), and introduced English ornamental hawthorn (C. monogyna). It is believed that R. pomonella was introduced to the Portland, OR, area via larval-infested apples from the east. The fly subsequently spread through the region, shifting onto black hawthorn and ornamental hawthorn as additional hosts as it spread. It is also possible, however, that R. pomonella is native to black hawthorn in the Pacific Northwest and switched to infest apple and ornamental hawthorn after the introduction of the...
TL;DR: Eight new state records and five new prey records for the wasp are here recorded, emphasizing the utility of C. fumipennis in documenting buprestid biodiversity and in detecting forest pests.
Abstract: ABSTBACT The solitary, ground-nesting crabronid wasp Cerceris fumipennis Say excels at detecting buprestid diversity in a given geographic area, and after the introduction of the invasive pest emerald ash borer (Agrilus planipennis Fairmaire) to the United States in 2002, has been developed as an effective tool for the biosurveillance of pest Buprestidae in eastern North America. Here we report records of Buprestidae collected from foraging C. fumipennis in 13 North Carolina counties over the course of three seasons (2009–2011). Nests of the wasp were located, and beetle prey collected from foraging females in three geographic regions, with a concentration on the western, mountainous area of the state. In total, 909 beetles were collected, comprising 52 buprestid species that included eight native pests and 17 species of Agrilus. Our results emphasize the utility of C. fumipennis in documenting buprestid biodiversity and in detecting forest pests. Eight new state records and five new prey records for the ...
TL;DR: Frequency of the net reproductive rate estimated by using bootstrap technique fit normal distribution well, whereas frequency data estimated byUsing jackknife technique failed the normality test, suggesting that the Jackknife technique should not be used for the estimation of population parameters.
Abstract: The life table and parasitism rate of Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae), a larval parasitoid of the diamondback moth Plutella xylostella (L.) (Lepidop- tera: Plutellidae), were studied at 25 1C, 65 10% RH, and a photoperiod of 16:8 (L: D) h. The data were analyzed based on the age-stage, two-sex life table theory. Because the sex ratio of offspring varies with the age of the female parent, we used only female offspring to calculate the intrinsic rate of increase (r), Þnite rate of increase (), net reproductive rate (R0), and mean generation time (T) by using the jackknife technique, the values of which were 0.18407 d 1 , 1.2021 d 1 , 17.94 offspring, and 15.69 d, respectively. We also calculated these parameters by using bootstrap technique. They were not signiÞcantly different from those estimated by using the jackknife technique. We included both male and female offspring in the calculation of the parasitism rate. The net parasitism rate (C0) was 42.63 aphids. Moreover, population projection showed differences between simulated population based on total offspring and female offspring. Because both the offspring sex ratio and the parasitism rate depend on female age, it is necessary to use the age-stage, two-sex life table for a correct analysis. Frequency of the net reproductive rate estimated by using bootstrap technique Þt normal distribution well, whereas frequency data estimated by using jackknife technique failed the normality test. We suggest that the jackknife technique should not be used for the estimation of population parameters.
TL;DR: This is the first study to identify laccase, glucose dehydrationrogenase, and xanthine dehydrogenase from L. hesperus saliva; it is proposed these enzymes target plant-defense compounds.
Abstract: ABSTBACT Lygus hesperus Knight (Hemiptera: Miridae) causes economic damage to a wide range of crops in the western United States. While stylet-probing, L. hesperus discharge saliva consisting of lytic enzymes that facilitate extraoral digestion of host tissues. L. hesperus saliva primarily consists of polygalacturonases, α-amylases, and proteases, but salivary constituents other than these enzymes have not been documented. Improved knowledge of L. hesperus salivary proteins could lead to a better understanding of Lygus-host interactions, and aid in the development of crops that are resistant or tolerant to injury caused by Lygus spp. The objective of our study was to use mass spectrometry to identify salivary proteins of L. hesperus adults. Multiple polygalacturonases and proteases were identified from diet that was stylet-probed and fed upon by L. hesperus. Laccase, alkyl hydroperoxide reductase-like protein, glucose dehydrogenase, and xanthine dehydrogenase were identified in styletprobed diets by using...
TL;DR: Examination of the population structure of Neoleucinodes elegantalis indicates that integrated pest management strategies used to control this species should consider the genetic differentiation of the species at different locations in Colombia.
Abstract: The purpose of this study was to examine the population structure of Neoleucinodes elegantalis (Guenee) (Lepidoptera: Crambidae) in relation to host plant association and ecological Holdridge zones. Adult collections were made in cultivated and wild Solanaceae species in 13 departments of Colombia. Sequencing of 658 bp of the mitochondrial gene Cytochrome Oxidase 1 on 103 individuals produced 25 haplotypes. Haplotypes Hl, H2, H4, and H7 were the most frequent and were geographically separated by the Andean mountains. We obtained an FST = 0.57 (P < 0.0001), where most of the genetic differentiation (42.64%) was between individuals within each department. Pairwise FST analysis produced higher genetic values between geographically separated departments than between closely related sites. H2 and H7 apparently behave as generalist populations, as they were found in different habitats and different hosts. The most divergent populations of N. elegantalis were found in southern Colombia, at a location we...
TL;DR: It is suggested that local selection pressures likely drive divergence in these two traits that is largely independent of the evolution of reproductive isolation in D. ponderosae.
Abstract: Body size and development time are two critical phenotypic traits that can be highly adaptive in insects. Recent population genetic analyses and crossing experiments with the mountain pine beetle (Dendroctonus ponderosae Hopkins) have described substantial levels of neutral molecular genetic differentiation, genetic differences in phenotypic traits, and reproductive isolation. To determine whether genetic differences in adaptive phenotypic traits exist that correspond to reproductive boundaries, we conducted a common garden experiment with seven D. ponderosae populations previously used to identify reproductive incompatibilities. Genetic differences in development time were striking between faster developing, and more synchronized, northern populations and slower developing, and less synchronized, southern populations. Additionally, genetic differences in average body size were found between many populations. Differences in these two traits, however, failed to clearly demarcate populations that exhibit reproductive incompatibilities. Our results suggest that local selection pressures likely drive divergence in these two traits that is largely independent of the evolution of reproductive isolation in D. ponderosae.
TL;DR: It is concluded that the host plant affects the development and survival of D. brevipes and that the choice of the most appropriate cultivar or vine rootstock can help to reduce pest infestation, and is therefore an additional component to be included in the integrated pest management of grapes.
Abstract: Dysmicoccus brevipes (Cockerell, 1893) (Hemiptera: Pseudococcidae) is one of the most frequent and abundant mealybugs in Brazilian vineyards, where it causes direct and indirect damage to the vines. In this study, we investigated the effect of plant structures, cultivars, and vine rootstocks on the development, survival, and reproduction of D. brevipes under laboratory conditions. Leaves of the tablegrape cultivar’ ‘Italia’ (Vitis vinifera) and ‘Niagara Rosada’ (Vitis labrusca) and the vine roots of the rootstocks Paulsen 1103 (Vitis berlandieri × V. rupestris) and IAC 572 (Vitis caribaea × 101-14 Mgt) were used as host plants. D. brevipes developed on different vegetative structures, cultivars, and vine rootstocks. D. brevipes showed the shortest developmental period and highest survival and fecundity rates on leaves of cultivar Italia. Survival on leaves was significantly higher than on roots. Roots of IAC 572 were unsuitable for D. brevipes development, resulting in nonreproductive females. Th...
TL;DR: Trap catches and species diversity were highest in chicken shelters at both urban and rural sites, followed by pigsties, and further work is needed to better understand abiotic and biotic factors affecting Culicoides populations of northeastern Brazil.
Abstract: Culicoides biting midges are medically important haematophagous flies that transmit diseases to animals and humans This work deals with the basic ecology of Culicoides populations in northeastern Brazil Adult biting midge populations in and around urban and rural communities were sampled monthly from September 2007 to October 2008 with light traps In total, 10,803 Culicoides midges representing 17 species were collected The most frequently collected species were Culicoides paucienfuscatus (83%), Culicoides leopoldoi (12%), Culicoides insignis (2%), and Culicoides paraensis (1%) Trap catches and species diversity were highest in chicken shelters at both urban and rural sites, followed by pigsties The Culicoides fauna is composed chiefly of species broadly distributed in the Neotropics Domestic animals are important factors for attracting and maintaining biting midge populations in peridomiciliary areas, especially C paucienfuscatus Further work is needed to better understand abiotic and biotic factors affecting Culicoides populations of northeastern Brazil
TL;DR: Interestingly, it is found for the first time that Mus musculus DNA was found in one female of S. minuta (Rondani) specie and question about its possible vectorial role is opened.
Abstract: ABSTBACT Knowledge of the host-feeding pattern of blood-sucking insects helps to understand the epidemiology of a vector-born disease. A set of primers was used to selectively amplify segment of vertebrates' prepronociceptin gene from abdomens of engorged sand flies. Vertebrate DNA was successfully amplified in 65% of blood-fed phlebotomines assayed. Direct sequencing and comparison of resultant sequences with sequences in GenBank, using Basic Local Alignment Search Tool, led to the specific identification of the host in 100% of the cases. In total, 249 blood-fed females belonging to five different sand flies species were captured thanks to Centers for Disease Control and Prevention light traps and sticky papers in different areas of Tunisia between 2007 and 2009. Bloodmeal origin was determined for 146 blood-fed midges: Phlebotomus sergenti Parrot sampled fed only on Ovis aries and Equus caballus, while bloodmeal origin of P. perniciosus Newstead, P. longicuspis Nitzulescu, and P. papatasi (Scopoli) was ...
TL;DR: Empirical evidence is provided that large-scale losses of species richness and changes in arthropod community structure are associated with the cultivation of domesticated rice.
Abstract: ABSTBACT Although it is well established that biodiversity plays an important role in pest control, there is limited knowledge on how the origins of agriculture may shape arthropod biodiversity. Arthropod food webs likely have coevolved with wild crop relatives before domestication, but not all arthropod taxa may be able to inhabit cultivated habitats. We sampled wild and cultivated rice fields in the Mekong Delta of Vietnam to determine how season (dry versus wet) and rice cultivation influenced arthropod diversity and community composition. We found that cultivated rice fields supported ≈50% fewer taxa than wild rice fields, and that there were widespread losses in taxonomic richness within all of the major orders. Wild rice fields supported 173 unique taxa that were not found in any cultivated rice fields, whereas cultivated rice (Oryza sativa L.) supported only 23 unique taxa. Furthermore, wild and cultivated rice supported different arthropod communities. Predators and parasitoids were the most abund...
TL;DR: Results show that A. pelleranoi develops better on larvae from An.
Abstract: Aganaspis pelleranoi (Brethes) (Hymenoptera: Figitidae) is an important fruit fly parasitoid native to the Neotropics. We investigated the biology and constructed a fertility life table for A. pelleranoi reared on larvae of Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Parasitoid development was investigated in larvae of the two fruit fly species by recording the duration of the egg-adult period, number of offspring, sex ratio, adult weight, adult hind tibia length, and male and female longevity, and constructing a fertility life table. Parasitoids reared on An. fraterculus larvae produced more offspring, had shorter egg-adult periods, greater proportion of females and longer survival, and higher percent emergence than parasitoids reared on C. capitata larvae. Moreover, A. pelleranoi individuals reared on An. fraterculus larvae were heavier and had longer hind tibia than those reared on C. capitata. Based on life table statistics, the time required ...
TL;DR: Phylogeographic patterns indicate an introduction of O. brumata in British Columbia likely originated from Germany, and suggest the invasive population in northeastern North America may have its origins in the United Kingdom, and/or Germany.
Abstract: The European winter moth, Operophtera brumata (L.), an invasive forest defoliator, is undergoing a rapid range expansion in northeastern North America. The source of this invasion, and phylogeographic diversity throughout its native range, has not been explored. To do this, we used samples from a pheromone-baited trap survey of O. brumata collected across its native range in Europe, and invasive range in North America. Traps in North America also attract a congeneric species, the Bruce spanworm O. bruceata (Hulst), and the western Bruce spanworm O. b. occidentalis (Hulst). From this sampling, we sequenced two regions of the cytochrome c oxidase subunit I mitochondrial gene; one region corresponds to the DNA ‘barcode’ region, the other is a nonoverlapping section. We used these sequences, in combination with sequence data from a recent survey of the Geometridae in western North America, for phylogenetic and phylogeographic analyses to characterize genetic divergence and variation for O. brumata in...
TL;DR: It is concluded that, as social insects, the presence of nestmates during the molting of individual termites reduced the time necessary to complete the ecdysis, and the histological description of the molted process provides a template for further studies on the effect of chitin synthesis inhibitors on ecDysis in termites.
Abstract: This study describes the behavioral and histological changes that take place during ecdysis in the Formosan subterranean termite. The molting process was described in four distinct phases, starting with the peristaltic contraction of the abdomen to the complete shedding of the exuvium. Although individual termites still managed to go through the molting process when isolated from their nestmates, it required more time for the molting individual to complete the process than when aided by its nestmates. Histological observations were made on termites during the intermolt period, the premolting or fasting period, the pre-ecdysis and the ecdysis periods, and on newly molted individuals. Symbiotic protozoans were voided at the beginning of the premolting/fasting period. The detachment and reattachment of the muscles of the abdominal segments occurred during pre-ecdysis, and the leg muscle detachment and reattachment occurred during ecdysis. During pre-ecdysis, the abdominal cuticle had a wrinkled texture and two layers of cuticles were observed, one of which was the newly formed cuticle underneath the old one. Finally, the old tracheae were shed from the tracheal system and were pulled out from the spiracular openings of the mesothorax with the help of the nestmates. We concluded that, as social insects, the presence of nestmates during the molting of individual termites reduced the time necessary to complete the ecdysis, and the histological description of the molting process provides a template for further studies on the effect of chitin synthesis inhibitors on ecdysis in termites.
TL;DR: Seasonal A. auroguttatus development, according to within-tree development and adult trap catch, was apparently 2 mo ahead at one site, which suggested that the level of current infestation affected host tree condition, or that dying tissue was more suitable for larval development.
Abstract: We investigated seasonal development of the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and physical conditions of the phloem within a preferred host species, coast live oak, Quercus agrifolia Nee. We sampled infested trees on a monthly basis at two sites in southern California throughout 2011. Measurements of an exposed portion of the head capsule, the peristoma, indicated that there were four larval instars. Pupae and teneral or mature adults were found within trees from April through August. Adults were captured in flight between May and mid-October, with peak flight from July through August. Within-tree A. auroguttatus prepupal mortality did not differ between sites and increased significantly from 3 ± 3% in January to 36 ± 9% in March (mean ± SE). Prepupae were present in trees throughout most of the year, which made it difficult to determine generation time; it was likely 1 yr for the majority of individuals, and possibly longer or shorter than 1 yr for others. Seasonal A. auroguttatus development, according to within-tree development and adult trap catch, was apparently 2 mo ahead at one site, which had a greater past and current level of A. auroguttatus infestation compared with the other. There was also evidence at the more severely infested site that within-tree A. auroguttatus population densities were positively related to proportion of dying phloem tissue. This suggested that the level of current infestation affected host tree condition, or that dying tissue was more suitable for larval development.
TL;DR: A new method using Gaussian mixture models to determine the number of instars in the cockroach, Blaptica dubia Serville, and indicates that there are seven instars and that the growth ratio follows the Brooks—Dyar rule.
Abstract: Instar determination is fundamental to both basic entomological research and its application. The cockroach, Blaptica dubia Serville (Blattodea: Blaberidae), is a popular pet and an excellent feeder insect for many reptiles and amphibians. A new method using Gaussian mixture models to determine the number of instars in this species is developed. Application of the method is illustrated by analysis of data collected on B. dubia. The analysis indicates that there are seven instars in B. dubia and that the growth ratio follows the Brooks—Dyar rule. The growth ratio of pronotal length, pronotal width, and head width are 1.26, 1.24, and 1.19, respectively. Because B. dubia shares a similar growth pattern with other paurometabolous insects, this method may be applicable to other species as well.
TL;DR: It is suggested that variation in the degree of ant attendance of this aphid is caused by aphid genotype, not by endosymbionts.
Abstract: Ant—aphid interactions are well-studied mutualisms, but surprisingly, the intraspecific variation in the degree of ant attendance of aphids has been less appreciated than interspecific variation. Honeydew composition is a key factor in determining aphids' traits in relation to the intensity of ant attendance, and composition may be altered by endosymbiotic bacteria. Here, we evaluate relationships among the intensity of ant attendance, honeydew composition, and aphids' endosymbionts. We found differences in the intensity of ant attendance and endosymbiont composition between clones of cowpea aphids (Aphis craccivora Koch). To investigate whether aphid genotype, endosymbionts, or both, influence honeydew composition, and the relative influence of these factors on the intensity of ant attendance, a secondary symbiont of the aphid, Arsenophonus, was removed from the clone exhibiting a lower degree of ant attendance. Then, the sugar and amino acid composition of honeydew were compared between differe...
TL;DR: Results show that the presence of C. formosanus can suppress the growth of Bti and Btt and the suppression effect enhanced with increased of group size, and antagonistic tests show that natural bacteria carried by termites play a role in the suppression of B ti and BTT.
Abstract: The Formosan subterranean termite, Coptotermes formosanus Shiraki, was studied for its ability to suppress two entomopathogenic bacteria, Bacillus thuringiensis subspecies israelensis (Bti) and thuringiensis (Btt). Different group sizes (50, 25, 10, and no termites [control]) of C. formosanus were placed on well-grown Bti or Btt agar plates. On day 1, the diameters of Bti and Btt colonies in the three treatments containing termites were significantly smaller than in the controls. The diameters of Bti and Btt colonies in the 50-termite treatment were significantly smaller than in the 10-termite treatment. However, neither was significantly different from the 25-termite treatment. This group sized dependent suppression was even more distinct on day 2. On day 5, inhibitory zones were observed in all three treatments containing termites where Bti or Btt colonies originally grew. The Bti and Btt cells from these inhibitory zones regenerated on new plates after transfer from 25- and 10-termite treatmen...
TL;DR: This is the first known instance of a species of Synergus emerging from Castanea galls (Fagaceae) and is described as a new species, Synergy castaneus Pujade-Villar, Bernardo et Viggiani sp.
Abstract: A species of the tribe Synergini (Hymenoptera: Cynipidae) was reared from a gall collected in China on Castanea mollissima Blume and Castanea seguinii Dode. The morphological features of this gall wasp indicate that it is an undescribed species belonging to the genus Synergus and is herein described as a new species, Synergus castaneus Pujade-Villar, Bernardo et Viggiani sp. nov. (Hymenoptera Cynipidae: Synergini). This is the first known instance of a species of Synergus emerging from Castanea galls (Fagaceae). Data on the diagnosis, distribution, and biology of the new species are given. Morphological features of this species are discussed and illustrated. No other known gall-inducing species emerged from the collected galls, whereas tens of specimens of parasitoids and adults of the inquiline micromoth Andrioplecta pulverula Meyrick (Lepidoptera: Tortricidae) did. 28S-D2 and COI sequences confirmed that S. castaneus is a distinct species belonging to the genus Synergus.
TL;DR: To distinguish Lepidoptera species commonly found in Brazil, the eggshells of all these species were morphologically characterized by scanning electron microscopy and a molecular diagnostic method using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis was developed to distinguish noctuid species commonly find in Brazil.
Abstract: The most important species of Lepidoptera that attack soybean, in descending order of importance, are Chrysodeixis includens (Walker), Anticarsia gemmatalis Hubner, Spodoptera cosmioides (Walker), Spodoptera eridania (Stoll), and Spodoptera albula (Walker). In addition, Rachiplusia nu ( Guenee ) is one of the most common Plusiinae in the southern region of Brazil, encompassing the states of Parana, Santa Catalina, and Rio Grande do Sul. The correct identification of these species is essential for choosing the appropriate control measures, as they differ in their susceptibility to insecticides and biological control agents. To distinguish Lepidoptera species commonly found in Brazil, the eggshells of all these species were morphologically characterized by scanning electron microscopy. Diagnostic characters for differentiating species include shape of rosette petals, number of primary cells, number of secondary cells, number of ribs, and rosette diameter. Also, a molecular diagnostic method using p...