Discrimination of Spartocera dentiventris (Berg, 1884) (Hemiptera: Coreidae) eggs by Gryon gallardoi (Brèthes, 1913) (Hymenoptera: Scelionidae).

This paper aimed to evaluate the stimuli that orient Gryon gallardoi females to the eggs of Spartocera dentiventris and allow their discrimination. Using a four-arm olfactometer connected to four odor sources--S. dentiventris eggs; hexane washed eggs; tobacco leaves; and tobacco leaves with eggs--the arrestment of female parasitoids with previous oviposition experience and without was individually verified. The time of permanence in each odor field was registered for a period of 15 minutes. Host discrimination, regarding age and previous parasitism, was tested using arenas, where females were exposed for 30 minutes, individually, to egg groups with different treatments. To evaluate age discrimination, three groups of eggs, previously washed with hexane, were employed in the following conditions: one day-old eggs; one-day brushed with 12-days-old egg extract; 12-days-old eggs with extract of one day-old eggs; and control (washed eggs, one day-old). The same procedure was done using five and eight days-old eggs jointly with control. Age-dependent egg discrimination was verified exposing four egg groups in the following treatments: parasitized, parasitized and washed with hexane, not parasitized, and not parasitized with extract of parasitized eggs. Olfactometer tests showed that inexperienced females remained more time next to tobacco leaves when compared to experienced ones. Experienced females responded to odors that emanated from eggs. Egg extracts did not promote age discrimination; however, non parasitized eggs, with extract of parasitized eggs were partially avoided. The results obtained indicate that G. gallardoi females might modify their responses upon contact with host. This fact suggests learning occurs; however, the acceptance and discrimination of host may be influenced by a complex array of stimuli, difficult to evaluate in isolation.     

Aleiodes Wesmael (Hymenoptera,Braconidae, Rogadinae) species described by Brèthes: taxonomic clarification

Two species of Doryctes Haliday 1836 described by Brèthes have their taxonomic status revised, and are transferred to the genus Aleiodes Wesmael 1838. The new combination and new names are: Aleiodes bonariensis (Brèthes, 1910) comb. n., and Aleiodes argentinensis nom. nov. The identity of Aleiodes bonariensis as a species is still doubtful, due to the poor condition in which the holotype is found, in addition to its general resemblance with Aleiodes gossypii (Muesebeck, 1960). The validity of the name Aleiodes brethesi (Shenefelt, 1975) (=Rhogas nigriceps Brèthes, 1909) is discussed and confirmed.     

Notes on the biology of Trypoxylon (Trypargilum) opacum Brèthes (Hymenoptera; Crabronidae) in Southern Brazil.

The present study investigated the abundance, seasonality and various life-history traits of Trypoxylon (Trypargilum) opacum. Using trap-nests, 320 nests of T. opacum were collected in the Parque Municipal das Araucárias in Southern Brazil (25 degrees 23' 36" S and 51 degrees 27' 19" W) over a 3 year period. Nesting was more frequent during the warm season. Nests consisted of a linear series of 1 to 8 brood cells separated by mud partitions, usually followed by an empty vestibular cell and final-closure mud plug. Brood cells were most commonly provisioned with spiders of the family Araneidae. Sex-ratio was strongly female biased, 3.4:1 females:males. Natural enemies attacking nests T. opacum included chrysidids, ichneumonids, sarcophagids, bombyliids and ants.     

Ultrastructural characterization of antennal sensilla and immunocytochemical localization of a chemosensory protein in Carausius morosus Brünner (Phasmida: Phasmatidae)

The aim of this work was to investigate the olfactory system of the walking stick insect, Carausius morosus. Morphological, ultrastructural and immunocytochemical studies of adult female antennae were conducted by scanning and transmission electron microscopy. Extensive cross-section series were made through the last antennal segment to define the cuticular apparatus, wall pore distribution and the number of innervating receptor neurons of each sensillum type. Single-walled wall pore sensilla occur in three subtypes: (i) with 27 or 28 branched receptor neurons, (ii) with two branched neurons and (iii) with one or two unbranched neurons, respectively. Double-walled wall pore sensilla were found in two subtypes with spoke channels, one with four unbranched neurons, the other with two unbranched neurons. One terminal pore sensillum was found, showing two cavities within the hair and being innervated by six sensory cells. Immunocytochemical experiments were performed to show the localization of a 19 kDa soluble protein found in the chemosensory organs of C. morosus. This protein shows an amino acid sequence homologous to the family of chemosensory proteins (CSP). The polyclonal antibody raised against the purified protein (CSP-cmA) showed, for the first time in CSPs, a strong labeling in olfactory sensilla, specifically in the sensillum lymph surrounding the dendritic branches of SW-WP sensilla and in the uninnervated lumen between the two concentric walls of DW-WP type 1 sensilla.     

Sensory organs inIps typographus (Insecta: Coleoptera) — Fine structure of antennal sensilla

Summary The antennal sensilla inI. typographus are almost exclusively confined to the flattened terminal flagellar segment. The sensillar types have distinct distribution patterns in the three areas where they are found. Judging from the ultrastructural characteristics the following functions can be assigned to the sensillar types: chemoreception, single-walled and double-walled sensilla; chemoreception/mechanoreception, terminal-pore sensillum. Moreover there are two types of mechanoreceptors, one of which is connected to a bristle, whereas the other terminates within the cuticle of the flagellar segment.This study was made within the Swedish project Odour Signals for Control of Pest Insects.     

Ultrastructure of the antennal sensilla of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae)

Insects have several types of sensilla, the characterization of which has been fundamental to understanding the mechanisms of sensory perception in different species. This study aimed to describe the ultrastructure of the sensilla present on the antennae of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae), an important pest of cotton (Gossypium hirsutum L.) crops, as well as their possible variation between sexes. To do this, the antennae of males and females of A. argillacea were analyzed using scanning electron microscopy. Sensilla morphometry was assessed using photomicrographs, from which the lengths and basal and apical diameters of sensilla were measured using the ImageJ program. Seven types of sensilla were identified on the antennae of A. argillacea: sensilla trichodea, sensilla chaetica, sensilla auricillica, sensilla coeloconica, sensilla styloconica, sensilla basiconica, and sensilla Böhm bristles. Differences between the sensilla of males and females were found in their lengths and basal diameters in the distal and proximal regions. This suggests that sensilla functionality may not only vary from one species to another, but also between sexes within the same species. Thus, further transmission electron microscopy and single sensillum recording studies may provide more detailed information on the sensilla of A. argillacea and their functions.     

Is the number of antennal plate organs (sensilla placodea) greater in hygienic than in non-hygienic Africanized honey bees?

Hygienic behavior is a desirable trait in honey bees (Apis mellifera L.), as hygienic bees quickly remove diseased brood, interrupting the infectious cycle. Hygienic lines of honey bees appear to be more sensitive to the odors of dead and diseased honey bee brood, and Africanized honey bees are generally more hygienic than are European honey bees. We compared the number of sensilla placodea, antennal sensory structures involved in the perception of odor, in 10 bees from each of six hygienic and four non-hygienic colonies of Africanized honey bees. The sensilla placodea of three of the terminal segments (flagellomeres) of the right antenna of each bee were counted with a scanning electron microscope. There were no significant differences in the mean numbers of sensilla placodea between the hygienic and non-hygienic bees, though the variance was higher in the hygienic group. Flagellomere 4 had significantly more sensilla placodea than flagellomeres 6 and 8. However, there was no significant difference between the other two flagellomeres. As hygienic bees are capable of identifying dead, injured, or infested brood inside a capped brood cell, sensilla placodea probably have an important role in enabling worker bees to sense sick brood. However, we did not find greater numbers of this sensory structure in the antennae of hygienic, compared to non-hygienic Africanized honey bees.     

New distribution and host records of chalcidoid parasitoids (Hymenoptera: Chalcidoidea) of scale insects (Hemiptera: Coccoidea) in Espírito Santo,Brazil

Three species of chalcidoid parasitoids of scale insects are recorded for the first time in Brazil: Adelencyrtus moderatus, Homalopoda sp., and Diglyphomorpha sp.; and new parasitoid–host associations are recorded between the chalcidoids Encarsia lounsburyi with Hemiberlesia palmae, Encarsia lounsburyi with Melanaspis smilacis, and Diglyphomorpha sp. with Dysmicoccus brevipes.     

Development, longevity and reproduction of Trissolcus basalis (Wollaston) and Telenomus podisi Ashmead (Hymenoptera: Scelionidae) in natural conditions during autumn and winter, in southern Paraná, Brazil

The development, longevity and reproduction of Trissolcus basalis (Wollaston) and Telenomus podisi Ashmead were investigated under natural conditions during autumn and winter from 1999 to 2001, in Southern Paraná State, Brazil, in order to understand how these parasitoids overwinter in subtropical regions. Adults of T. basalis e T. podisi emerged during autumn and winter from eggs parasitized between April and June. Adult longevity in natural conditions was higher than eight and seven months, for T. basalis and T. podisi respectively, showing that both species overwinter in the adult stage. Percentage survival of T. basalis and T. podisi females during autumn and winter was higher than 85% and mortality increased significantly in spring. Females maintained for six months in natural conditions parasitized E. heros eggs after transference to 25 degrees C, and the presence of females in the offspring showed that mating occurred during autumn and winter. Temperature during immature development influenced significantly the adult performance, regulating the longevity and reproductive capacity after dormancy. Female parasitoids that developed in higher temperatures lived longer and parasitized more host eggs after transference to 25 degrees C than females that developed under colder conditions.     

Review of <Emphasis Type="Italic">Dotocryptus</Emphasis> Brèthes (Hymenoptera,Ichneumonidae, Cryptinae), with a New Species from Colombia

The taxonomic limits of the Neotropical genus Dotocryptus Brèthes are reviewed. The genus is characterized mainly by the very long ovipositor, at least 2.2× as long as hind tibia; apex of ovipositor distinctly depressed, ventral valve expanded, and overlapping dorsal valve as a sheath; and mandible long with ventral tooth longer than dorsal one. A new species, Dotocryptus arcadius sp. nov., from Colombia is described and illustrated. The new species can be diagnosed mainly by the head and mesosoma with multiple whitish marks; epicnemial carina reaching 0.2–0.3 of distance to subalar ridge; legs marked with dark brown, orange, and whitish; and metasoma polished and glabrate. This is the northernmost record of the genus, previously known from Ecuador to southern Chile. An updated identification key to the species of the genus is provided, as well as diagnoses and new records for the previously known species.     

Effects of Endophyte Colonization of Vicia faba (Fabaceae) Plants on the Life–History of Leafminer Parasitoids Phaedrotoma scabriventris (Hymenoptera: Braconidae) and Diglyphus isaea (Hymenoptera: Eulophidae)

Effects of the fungal endophytes Beauveria bassiana (isolates ICIPE 279, G1LU3, S4SU1) and Hypocrea lixii (isolate F3ST1) on the life-history of Phaedrotoma scabriventris and Diglyphus isaea, parasitoids of the pea leafminer Liriomyza huidobrensis, were studied in the laboratory. Parasitoids were allowed to parasitize 2^nd and 3^rd instar L. huidobrensis larvae reared on endophytically-inoculated faba bean, Vicia faba. In the control, parasitoids were reared on non-inoculated host plants. Parasitism, pupation, adult emergence and survival were recorded. No significant difference was observed between the control and the endophyte-inoculated plants in terms of parasitism rates of P. scabriventris (p = 0.68) and D. isaea (p = 0.45) and adult'' survival times (p = 0.06). The survival period of the F1 progeny of P. scabriventris was reduced (p<0.0001) in B. bassiana S4SU1 to 28 days as compared to more than 40 days for B. bassiana G1LU3, ICIPE 279 and H. lixii F3ST1. However, no significant difference (p = 0.54) was observed in the survival times of the F1 progeny of D. isaea. This study has demonstrated that together, endophytes and parasitoids have beneficial effects in L. huidobrensis population suppression.     

External antennal morphometry of Trichoplusia Ni (Hübner) (Lepidoptera: Noctuidae)

A detailed morphometric analysis of the antennae of male and female Trichoplusia ni (Hübner) is presented, based on light and scanning electron microscopic observations. These measurements of general antennal dimensions and the number, distribution, dimensions, and surface features of the antennal sensilla are applied in the consideration of olfactory transduction processes and in the derivation of a mathematical representation of the antennal surface. The surface area and the number of sensilla on the antennal flagellum are found to vary with the weight of the pupa and adult moth. The long Type 1 sensilla trichodea are hypothesized to be innervated by pheromone-sensitive olfactory cells on the basis of morphological comparisons with sensilla of other insects.     

Morphology and distribution of trichomes in Italian species ofTeucrium sect.Chamaedrys (Labiatae) — a taxonomical evaluation

Micromorphology and distribution of trichomes (both secretory and not) in different parts of plants of the five Italian species belonging toTeucrium sect.Chamaedrys have been studied. These characters neatly evidence the differences between the taxa considered; of particular interest are the observations concerning the dense coverage of peltate hairs on the abaxial face of the leaves ofT. flavum subsp.glaucum and the characters contributing to a better identification ofT. marum andT. subspinosum. The importance of the calyx indumentum as distinctive taxonomical character of the genusTeucrium is confirmed, stressing at the same time the necessity of completing the observations at micromorphological level.     

Conservation study of an endangered stingless bee (Melipona capixaba—Hymenoptera: Apidae) with restricted distribution in Brazil

Melipona capixaba, popularly known as “uruçu preta”, is a stingless bee restricted to the mountainous Atlantic Rainforest areas of Espírito Santo State, Brazil. Due to the endemism and small population size, this species discovered in 1994 is now considered “vulnerable to extinction”. Using ISSR, PCR–RFLP and microsatellites markers, we studied the genetic variability and structure of M. capixaba from 88 colonies collected throughout the distribution area of the species within Espírito Santo State. The microsatellite, ISSR and mitochondrial haplotype analyses showed that M. capixaba has low genetic variability compared to other insect species. The molecular analyses also indicated a high genetic similarity among the M. capixaba samples, with no clear pattern of structuring. The analyses of molecular variance results indicated that most of the total genetic variation in M. capixaba was explained by the genetic diversity within local populations. Results suggest that the analyzed samples could be treated as a single population for preservation purposes. Thus, given its endemism, local adaptation and low number of natural colonies, efforts for the conservation of M. capixaba should focus on preservation and increasing the number of colonies in the wild, so that M. capixaba can support constant captures and the effects of habitat deforestation in Espírito Santo State.     

Development and parasitization of an aphid’s secondary parasitoid,Dendrocerus laticeps (Hymenoptera: Megaspilidae), on Aphidius colemani (Hymenoptera: Braconidae)

Banker-plant systems using Aphidius species have been employed to control pest aphids in greenhouses growing eggplant and sweet pepper in Japan. However, a strong negative correlation between the occurrence of secondary parasitoids and aphid-control success by this system was reported by Nagasaka et al. (2010). To control secondary parasitoid populations, detailed knowledge of their ecological characteristics is needed. In this paper, the development and parasitization ability of Dendrocerus laticeps (Hedicke) (Hymenoptera: Megaspilidae), a major secondary ectoparasitoid of Aphidius species in Japan, were examined under 25 °C laboratory conditions. The maximum female longevity was about 11 days when honeydew was available. Parasitization occurred only on mummified aphids, and the age of mummified aphids did not influence the ecological value of offspring. The maximum parasitization ability was 18.9 hosts/day estimated by Holling’s disc equation. Possible lifetime fecundity was 100.35. The intrinsic rate of natural increase estimated by the bootstrap method ranged from 0.211 to 0.321, depending on the assumptions made about larval mortality. The countermeasures for avoiding the negative impacts of D. laticeps in a banker-plant system include the development of a refuge for mummified aphids and increasing the temperature around the banker plants.     

Differences in larval emergence chronotypes for sympatric Rhagoletis brncici Frías and Rhagoletis conversa (Bréthes) (Diptera,Tephritidae)

In central Chile, Rhagoletis brncici and R. conversa, can be found in sympatry, associated with the fruit of their native host plants: Solanum tomatillo and S. nigrum (Solanaceae), respectively. Third-stage larvae must emerge from its host in search of pupation sites, and during this period larvae must find an appropriate pupation microhabitat while avoiding predation and adverse abiotic factors. In this study, we explored whether these sympatric species differ in terms of the timing of their larval exit from the host fruit in search of pupation sites. Field-collected fruits from host plants were checked daily for larval emergence, within 24 h, under laboratory conditions, in order to determine the time of the event. We found that these species differed significantly in their diel larval emergence. For R. brncici, most larvae left the host fruit between late evening and past midnight, meanwhile larvae from R. conversa concentrated their peak of emergence near midnight and early morning. We discuss these findings in terms of the ecological and evolutionary implications of the temporal separation of larval emergence regarding the use of pupation sites, abiotic stress and risk of predation for these sympatric species.     

A new genus and species of Eulophidae (Hymenoptera:Chalcidoidea) parasitizing Hyphantria cunea(Drury) (Lepidoptera:Arctiidae) in China

In the spring of 1985, a species of chaicid wasps was reared from the pupae of fall webworm, Hyphantria cunea (Drury) (Lepidoptera:Arctiidae) during myinvestigation on the parasitoids of this introduced harmful insect pest inShaanxi Province, China. With high parasitic ratio (over 80 percent) and a largenumber of individuals (over 200 were usually reared from a single pupa of the