Gall inducing arthropods from a seasonally dry tropical forest in Serra do Cipó, Brazil

Highly diverse forms of galling arthropods can be identified in much of southeastern Brazil's vegetation. Three fragments of a Seasonally Dry Tropical Forest (SDTF) located in the southern range of the Espinhaço Mountains were selected for study in the first survey of galling organisms in such tropical vegetation. Investigators found 92 distinct gall morphotypes on several organs of 51 host plant species of 19 families. Cecidomyiidae (Diptera) was the most prolific gall-inducing species, responsible for the largest proportion of galls (77%) observed. Leaves were the most frequently galled plant organ (63%), while the most common gall morphotype was of a spherical shape (30%). The two plant species, Baccharis dracunculifolia (Asteraceae) and Celtis brasiliensis (Cannabaceae), presented the highest number of gall morphtypes, displaying an average of 5 gall morphotypes each. This is the first study of gall-inducing arthropods and their host plant species ever undertaken in a Brazilian SDTF ecosystem. Given the intense human pressure on SDTFs, the high richness of galling arthropods, and implied floral host diversity found in this study indicates the need for an increased effort to catalogue the corresponding flora and fauna, observe their intricate associations and further understand the implications of such rich diversity in these stressed and vulnerable ecosystems.

Within tree distribution of a gall-inducing Eurytoma (Hymenoptera, Eurytomidae) on Caryocar brasiliense (Caryocaraceae)

For the first time, we identified the insect herbivore that induces one of the most conspicuous galls on the leaves of Caryocar brasiliense Camb. (Caryocaraceae), a widespread, typical cerrado woody plant of large economic importance. The gall inducing organism is a new and undescribed species of Eurytoma sp. (Hymenoptera, Eurytomidae). Furthermore, we recorded its spatial distribution within C. brasiliense trees. More Eurytoma galls were found on the eastern tree slope, followed the southern and northern slopes. More galls were found in the interior of the tree crown, i.e., on the proximal portion of the stems compared to the terminal portion. At the leaf level, more galls were found on the median region compared to the distal or proximal, perhaps due to the lower trichome density found in there. Leaf colonization by Eurytoma sp. may initiate at the leaf margin but after colonization reaches 50% the central portion starts to be colonized.

A new genus and species of gall midge (Diptera, Cecidomyiidae) associated with Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) from Brazil

A new genus and species of gall midge (Diptera, Cecidomyiidae) associated with Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) from Brazil. A new gall midge genus Primadiplosis Maia, gen. nov. and a new species, P. microgrammae Maia,sp. nov., that induces galls on stems of the fern Microgramma vacciniifolia (Langsd. & Fisch.) Copel. are described from Brazil (larva, pupa, male, female, and gall).

Richness of gall-inducing insects in the tropical dry forest (caatinga) of Pernambuco

Diversity of gall-inducing insects in the tropical dry forest (caatinga) of Pernambuco. We report on the richness of galling insects in the vegetation of caatinga of Pernambuco state, Brazil. We recorded 64 different types of galls collected primarily from leaves and stems of 48 species of host plants belonging to 17 families and 31 genera. The most common gall morphological types were spheroid and discoid, glabrous, predominantly green and with one chamber. The main gall inducing taxon was the Cecidomyiidae (Diptera). The results of this study contribute to existing knowledge of galling insect and host-plant diversity in caatinga.

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae)

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae). Studies on Ceratitis capitata, a world fruit pest, can aid the implementation of control programs by determining the plants with higher vulnerability to attacks and plants able to sustain their population in areas of fly distribution. The objective of the present study was to evaluate the influence of eight tropical fruits on the following biological and behavioral parameters of C. capitata: emergence percentage, life cycle duration, adult size, egg production, longevity, fecundity, egg viability, and oviposition acceptance. The fruits tested were: acerola (Malpighia glabra L.), cashew (Anacardium occidentale L.), star fruit (Averrhoa carambola L.), guava (Psidium guajava L.), soursop (Annona muricata L.), yellow mombin (Spondias mombin L.), Malay apple (Syzygium malaccense L.), and umbu (Spondias tuberosa L.). The biological parameters were obtained by rearing the recently hatched larvae on each of the fruit kinds. Acceptance of fruits for oviposition experiment was assessed using no-choice tests, as couples were exposed to two pieces of the same fruit. The best performances were obtained with guava, soursop, and star fruit. Larvae reared on cashew and acerola fruits had regular performances. No adults emerged from yellow mombin, Malay apple, or umbu. Fruit species did not affect adult longevity, female fecundity, or egg viability. Guava, soursop, and acerola were preferred for oviposition, followed by star fruit, Malay apple, cashew, and yellow mombin. Oviposition did not occur on umbu. In general, fruits with better larval development were also more accepted for oviposition.

Spatial distribution of a spherical gall (Hymenoptera, Eulophidae) on Caryocar brasiliense (Caryocaraceae)

We obtained the first data on spatial distribution of a spherical galling insect (Hymenoptera, Eulophidae) at the Caryocar brasiliense Camb. (Caryocaraceae) tree level. This work was developed in two pastures in Montes Claros, Minas Gerais State, Brazil. The areas studied were: pasture 1 (in activity) and pasture 2 (abandoned pasture = savanna in recovery). We evaluated the distribution of spherical galls in: foliage orientation (slope), among leaves (border and interior of the tree crown), among leaflets (right, central, left), distal, median, and proximal as well as border, central area, and adjacent to the mid leaf vein of the leaflet, and difference between areas in 10 infested trees per area. The smaller number of spherical gall/leaflet was observed in pasture 1 than in pasture 2. More spherical galls were found on the northern in pasture 1, but in the pasture 2, the lower spherical galls were observed on the northeast than other slopes. The average number of spherical galls did not differ statistically among the three leaflets of C. brasiliense in pasture 2. However, in pasture 1, we observed highest number of spherical galls in the central leaflet. More spherical galls were found in the border than interior of the tree crown. The average number of spherical galls did not differ statistically among the longitudinal region on leaflet of C. brasiliense. The spherical gall insect preferred to colonize the leaf margin than the central portion or near mid vein on transversal regions on a leaflet.

The effect of environment on development and survival of pupae of the necrophagous fly Ophyra albuquerquei Lopes (Diptera, Muscidae)

The effect of environment on development and survival of pupae of the necrophagous fly Ophyra albuquerquei Lopes (Diptera, Muscidae). Species of Ophyra Robineau-Desvoidy, 1830 are found in decomposing bodies, usually in fresh, bloated and decay stages. Ophyra albuquerquei Lopes, for example, can be found in animal carcasses. The influence of environmental factors has not been evaluated in puparia of O. albuquerquei. Thus, the focus of this work was motivated by the need for models to predict the development of a necrophagous insect as a function of abiotic factors. Colonies of O. albuquerquei were maintained in the laboratory to obtain pupae. On the tenth day of each month 200 pupae, divided equally into 10 glass jars, were exposed to the environment and checked daily for adult emergence of each sample. We concluded that the high survival rate observed suggested that the diets used for rearing the larvae and maintaining the adults were appropriate. Also, the data adjusted to robust generalized linear models and there were no interruptions of O. albuquerquei pupae development within the limits of temperatures studied in southern Rio Grande do Sul, given the high survival presented.

On the first tachinid fly (Diptera, Tachinidae) carrying Asclepiadoideae pollinaria in the Neotropical Region

On the first tachinid fly (Diptera, Tachinidae) carrying Asclepiadoideae pollinaria in the Neotropical Region. This paper reports the first Neotropical Tachinidae species possibly associated to pollination of Asclepiadoideae: a female of Euacaulona sumichrasti Townsend, 1908 (Diptera, Tachinidae, Phasiinae, Trichopodini) carrying pollinaria of Gonolobus parviflorus Decne., 1844 (Apocynaceae, Asclepiadoideae, Asclepiadeae: Gonolobinae) attached to its proboscis. The fly specimen was collected in Paraguay, Departamento Canindeyú. The pollinarium is illustrated and described herein. This represents the first anthophilous record to G. parviflorus and to the genus.

Do fly parasites of bats and their hosts coevolve?speciation in Trichobius phyllostomae group (Diptera, Streblidae) and their hosts (Chiroptera, Phyllostomidae) suggests that they do not

We examined whether, like many parasite-host systems of coevolution, a group of obligate parasitic bat flies (Trichobius phyllostomae Kessel and related species) cospeciate with their hosts. We first did a cladistic analysis of the T. phyllostomae group and combined that analysis with a phylogenetic hypothesis from the literature for the Stenodermatinae bats. The cladistic analysis included, as outgroups, one species from each morphological group and complex of Trichobius Gervais, and one species from the following genera: Paratrichobius Miranda-Ribeiro, Megistopoda Macquart, Megistapophysys Dick & Wenzel, Neotrichobius Wenzel & Aitken, Speiseria Kessel and Strebla Wiedemann. The cladogram was rooted with a species of Strebla in the subfamily Streblinae. One cladogram was obtained and which found Trichobius to be polyphyletic. The phylogenetic hypothesis as follows: (Paratrichobius, (Neotrichobius, (Megistopoda, Megistapophysis)))) is the sister-group of the phyllostomae group and the following relationships within the ingroup, (((T. vampyropis Wenzel, Trichobius sp. 2) ((T. hispidus Wenzel, T. petersoni Wenzel) ((Trichobius sp. 1 (T. phyllostomae, T. brennani Wenzel))))). When we compared phylogenies through historical association analyses, cospeciation was uncommon, while host-switching was more common and better explained the association between the phyllostomae group and their bat hosts.

Gall-inducing insects of an Araucaria Forest in southern Brazil

Gall-inducing insects of an Araucaria Forest in southern Brazil. Diversity of galling insects is reported for the first time in an Araucaria Forest site. We address gall characteristics, host plant identification and the inducer identification and provide additional information about sites of gall occurrence in a mosaic of continuous forest and natural forest patches. After 40h of sampling we found 57 species of five insect orders, the majority of them Diptera (Cecidomyiidae), galling 43 host plant species, which in turn belonged to 18 host plant families. Stem and buds together, compared to leaves, harbored more galls, which were mostly glabrous, isolated, fusiform and green. Myrtaceae, Asteraceae and Melastomataceae were the most representative host families. Similarities in gall characteristics to what has been reported in the literature probably result from spatial correlation in a larger scale driven by ecological and evolutionary processes.

Description of the immature stages of the weevil Anthonomus vis Clark (Coleoptera, Curculionidae), inquiline into the gall of Leandra aurea (Melastomataceae)

Description of the immature stages of the weevil Anthonomus vis Clark (Coleoptera, Curculionidae), inquiline into the gall of Leandra aurea (Melastomataceae). The third instar larva and the pupa of Anthonomus vis Clark, 1992 are described and illustrated, based upon specimens collected in the Serra de São José, Tiradentes, in Minas Gerais, southeastern Brazil. The species was previously known from the type series collected in the states of Amapá and Pará. Comparisons with the larva and pupa of A. grandis Boheman, 1843 and A. monostigma Champion, 1903 are included. The larvae of A. vis live as inquilines in the galls induced by a species of momphid moths (Lepidoptera, Momphidae) in the stems of Leandra aurea (Cham.) Cogn. (Melastomataceae).

Morphology, distribution and abundance of antennal sensilla of the oyster mushroom fly, Coboldia fuscipes (Meigen) (Diptera: Scatopsidae)

ABSTRACT We investigated the distribution, morphology and abundance of antennae sensilla of Coboldia fuscipes (Meigen) using scanning electron microscopy. Antennae of C. fuscipes consisted of scape, pedicel, and flagellum with eight flagellomeres. Antennal scape and pedicel had only one type of sensillum, i.e., sensilla chaetica. Significant differences were found between the number and distribution of these sensilla. Four types of morphologically distinct sensilla on the flagellum were identified, including sensilla chaetica, sensilla trichoidea, sensilla coeloconica, and sensilla basiconica (three subtypes). Significant differences were found in the abundance and distribution of sensilla among the antennal flagella and diverse flagellomeres in both sexes. Sensilla trichoidea is the most abundant of sensilla discovered on the antennal flagellum. Sensilla chaetica is the largest and longest sensilla among all the types of sensilla found on the antennal surface of C. fuscipes. Sensilla coeloconica is widely distributed all over the flagellum surface except for the first of female. Some significant differences in the abundance and distribution were also observed among sensilla basiconica of flagellum. The probable biological function of each sensillum type was deduced based on the basis of their structure. These results serve as important basis for further studies on the host location mechanism and mating behavior of C. fuscipes.

Determination of the critical period of weed control in corn using a thermal basis

Field studies were conducted over 3 years in southeast Buenos Aires, Argentina, to determine the critical period of weed control in maize (Zea mays L.). The treatments consisted of two different periods of weed interference, a critical weed-free period, and a critical time of weed removal. The Gompertz and logistic equations were fitted to relative yields representing the critical weed-free and the critical time of weed removal, respectively. Accumulated thermal units were used to describe each period of weed-free or weed removal. The critical weed-free period and the critical time of weed removal ranged from 222 to 416 and 128 to 261 accumulated thermal units respectively, to prevent yield losses of 2.5%. Weed biomass proved to be inverse to the crop yield for all the years studied. When weeds competed with the crop from emergence, a large increase in weed biomass was achieved 10 days after crop emergence. However, few weed seedlings emerged and prospered after the 5-6 leaf maize stage (10-20 days after emergence).

Soil solarization for weed control in carrot

Soil solarization is a technique used for weed and plant disease control in regions with high levels of solar radiation. The effect of solarization (0, 3, 6, and 9 weeks) upon weed populations, carrot (Daucus carota L. cv. Brasília) yield and nematode infestation in carrot roots was studied in São Luís (2º35' S; 44º10' W), MA, Brazil, using transparent polyethylene films (100 and 150 mm of thickness). The maximum temperature at 5 cm of depth was about 10ºC warmer in solarized soil than in control plots. In the study 20 weed types were recorded. Solarization reduced weed biomass and density in about 50% of weed species, including Cyperus spp., Chamaecrista nictans var. paraguariensis (Chod & Hassl.) Irwin & Barneby, Marsypianthes chamaedrys (Vahl) O. Kuntze, Mitracarpus sp., Mollugo verticillata L., Sebastiania corniculata M. Arg., and Spigelia anthelmia L. Approximately 40% of species in the weed flora were not affected by soil mulching. Furthermore, seed germination of Commelina benghalensis L. was increased by soil solarization. Marketable yield of carrots was greater in solarized soil than in the unsolarized one. It was concluded that solarization for nine weeks increases carrot yield and is effective for controlling more than half of the weed species recorded. Mulching was not effective for controlling root-knot nematodes in carrot.

Use of solaria to predict weed density and floristic composition in no-till cropping systems

The objective of this work was to evaluate the efficiency of a new method, developed for predicting density and floristic composition of weed communities in field crops. Based on the use of solaria (100 mm transparent plastic tarps lying on the soil) to stimulate weed seedlings emergence, the method was tested in Tandil, Argentina, from 1998 to 2001. The system involved corn and sunflower in commercial no-till system. Major weeds in the experiments included Digitaria sanguinalis, Setaria verticillata and S. viridis, which accounted for 98% of the weed community in the three years of experiments since 1998. Large numbers of Tagetes minuta, Chenopodium album and Ammi majus were present in 2001. Comparison of weed communities under solaria with communities in field crops indicated that the method is useful for predicting the presence and density of some major weed species, at both high and low densities, of individuals in areas of 10 ha using only five solaria. Low density of weed species makes the method particularly useful to help deciding the time for herbicide applications to avoid soil contamination.