A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins

Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin ~100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants.

Evolutionary trade-offs between male secondary sexual traits revealed by a phylogeny of the hyperdiverse tribe Eumaeini (Lepidoptera: Lycaenidae)

Male butterflies in the hyperdiverse tribe Eumaeini possess an unusually complex and diverse repertoire of secondary sexual characteristics involved in pheromone production and dissemination. Maintaining multiple sexually selected traits is likely to be metabolically costly, potentially resulting in trade-offs in the evolution of male signals. However, a phylogenetic framework to test hypotheses regarding the evolution and maintenance of male sexual traits in Eumaeini has been lacking. Here, we infer a comprehensive, time-calibrated phylogeny from 379 loci for 187 species representing 91% of the 87 described genera. Eumaeini is a monophyletic group that originated in the late Oligocene and underwent rapid radiation in the Neotropics. We examined specimens of 818 of the 1096 described species (75%) and found that secondary sexual traits are present in males of 91% of the surveyed species. Scent pads and scent patches on the wings and brush organs associated with the genitalia were probably present in the common ancestor of Eumaeini and are widespread throughout the tribe. Brush organs and scent pads are negatively correlated across the phylogeny, exhibiting a trade-off in which lineages with brush organs are unlikely to regain scent pads and vice versa. In contrast, scent patches seem to facilitate the evolution of scent pads, although they are readily lost once scent pads have evolved. Our results illustrate the complex interplay between natural and sexual selection in the origin and maintenance of multiple male secondary sexual characteristics and highlight the potential role of sexual selection spurring diversification in this lineage.

Atlantic butterflies: a data set of fruit-feeding butterfly communities from the Atlantic forests

Butterflies are one of the best-known insect groups, and they have been the subject of numerous studies in ecology and evolution, especially in the tropics. Much attention has been given to the fruit-feeding butterfly guild in biodiversity conservation studies, due to the relative ease with which taxa may be identified and specimens sampled using bait traps. However, there remain many uncertainties about the macroecological and biogeographical patterns of butterflies in tropical ecosystems. In the present study, we gathered information about fruit-feeding butterfly species in local communities from the Atlantic Forests of South America. The ATLANTIC BUTTERFLIES data set, which is part of ATLANTIC SERIES data papers, results from a compilation of 145 unpublished inventories and 64 other references, including articles, theses, and book chapters published from 1949 to 2018. In total, the data set contains 7,062 records (presence) of 279 species of fruit-feeding butterflies identified with taxonomic certainty, from 122 study locations. The Satyrini is the tribe with highest number of species (45%) and records (30%), followed by Brassolini, with 13% of species and 12.5% of records. The 10 most common species correspond to 14.2% of all records. This data set represents a major effort to compile inventories of fruit-feeding butterfly communities, filling a knowledge gap about the diversity and distribution of these butterflies in the Atlantic Forest. We hope that the present data set can provide guidelines for future studies and planning of new inventories of fruit-feeding butterflies in this biome. The information presented here also has potential use in studies across a great variety of spatial scales, from local and landscape levels to macroecological research and biogeographical research. We expect that such studies be very important for the better implementation of conservation initiatives, and for understanding the multiple ecological processes that involve fruit-feeding butterflies as biological indicators. No copyright restrictions apply to the use of this data set. Please cite this Data paper when using the current data in publications or teaching events.

Winter is coming: Diapause in the subtropical swallowtail butterfly Euryades corethrus (Lepidoptera, Papilionidae) is triggered by the shortening of day length and reinforced by low temperatures

Diapause is modulated by genetic responses to some environmental cues. The most common stimulus to trigger diapause is photoperiod, but temperature and humidity can also be important. Subtropical grasslands insects are overexposed to seasonality and can use diapause as strategy to overcome harsh conditions, avoiding freezing winter temperatures and drought summer conditions. Here, we investigate if photoperiod, temperature, and humidity can induce and terminate dormancy using the model Euryades corethrus, a butterfly from Pampa that diapause as pupae. We hypothesize that photoperiod, temperature, and humidity can induce dormancy; to test the hypothesis, individuals from a stock population were subjected to experiments controlling these three factors. Photoperiod and temperature interactions were also tested. To evaluate if the removal of the harsh factor that induced diapause trigger diapause termination, 50% of dormant pupae in each experiment were exposed to amenable conditions. The results indicated that diapause is mainly induced by short photophases, while temperature and humidity separately do not increase dormancy frequency. Short photoperiods and low temperatures interact with each other, increasing dormancy in experimental populations. The evidences suggest that diapause is trigger by short-day lengths and boosted by low temperatures as winter approaches. The incidence of obligatory summer diapause was not supported, but the occurrence of dormant pupae in high-temperature treatments suggests that high temperatures produce facultative diapause. Regarding diapause termination, the softening of harsh conditions that induced diapause was not sufficient to reverse the dormancy state, suggesting that diapause termination is more complex than previously thought, probably involving internal clocks.

Monitoring Temporal Variation to Assess Changes in the Structure of Subtropical Atlantic Forest Butterfly Communities

The study of fauna through long-term surveys is important in unveiling how temporal patterns shape the structure of communities in tropical habitats. The butterfly assemblage of the subtropical Atlantic Forest may be considered highly diverse and shows changes in diversity and composition over time, highlighting the importance of long-term inventories. This work assessed temporal diversity patterns in the distribution and composition of butterfly assemblages in an Atlantic Forest site in southern Brazil using combined data from three years of standardized sampling with entomological nets, increasing the knowledge on this group in the Neotropics for monitoring and conservation. The butterfly fauna was analyzed in terms of richness, abundance, and composition. The inventories reached 401 species, with 14,442 butterfly individuals sampled. All the diversity parameters evaluated show significant differences between the first year of sampling compared to the second and third years. The latter had higher values of richness and abundance, followed by the first and second years. Hesperiidae was the richest family, followed by Nymphalidae and Lycaenidae, indicating a good representation of the assemblage as a whole. The results of this work are important for developing conservation programs in the Atlantic Forest and other forested environments in the neotropics, especially concerning reliable diversity assessments for the monitoring and management of protected areas. Decision making and public policy might also benefit from knowledge on temporal patterns of diversity regarding the maintenance of native habitats and integrity of biomes and their associated fauna.

Population Dynamics of the Swallowtail Butterfly Battus polystictus polystictus (Butler) (Lepidoptera: Papilionidae) with Notes on Its Natural History

Battus polystictus (Butler) is a butterfly from the Neotropical region, occurring in the Atlantic Forest and Pampa biomes. It is commonly found in forest fragments surrounded by meadow formations, subjected to marked seasonal changes. Here, we report the population dynamics of B. polystictus at a high latitude environment and provide notes on its natural history. Population parameters were estimated on a 12-month mark-recapture program and the seasonality of resources investigated by exhaustive mapping of host-plants and flowers. The number of butterflies per day was not stable during the year, ranging from zero (winter) to 22 (summer); the sex ratio was always male biased (3M:1F). The age structure was not constant, with an increase of older individuals toward summer. The population density was positively correlated with temperature, relative humidity, and day length. The residence time was lower for males, while the vagility was lower for females; the increment of resources at forest edges seems to increase the likelihood of occurrence of both sexes. The results shown here suggest that South Brazilian populations of B. polystictus have high ecological demands for spring and summer conditions, avoiding winter in diapause.

Butterflies (Lepidoptera: Papilionoidea and Hesperioidea) of the Banhado dos Pachecos Wildlife Refuge, Uruguayan Savanna Ecoregion, Rio Grande do Sul state, Brazil

The Pampa is a biome shared by Argentina, Brazil, and Uruguay. Despite its high biodiversity, little is known about the invertebrate fauna. The few inventories done so far were conducted outside protected areas, which could result in underestimated real biodiversity. Thus, species inventories from protected areas should be done to serve as reference for conservation. Here we survey the butterflies occurring in the Banhado dos Pachecos Wildlife Refuge, Uruguayan Savanna, Brazil. Sampling was performed between April 2012 and March 2013. After 288 hours of sampling, 1,508 individuals from 113 species were sampled; five new species records for Rio Grande do Sul state and 12 for the Uruguayan Savanna were found. Richness among families was compared to other inventories and butterfly conservation discussed concerning the conversion of grasslands into croplands/pastures. The evidence presented supports that the Pampa is a fragile environment under the pressure of habitat conversion. Biodiversity studies in fragmented areas are needed to provide essential information for conservation programs.

Borboletas (Lepidoptera: Papilionoidea e Hesperioidea) de Matas Paludosas e Matas de Restinga da Planície Costeira da região Sul do Brasil

Este trabalho teve como objetivo elaborar uma lista de espécies de borboletas de Matas Paludosas e de Restingas da Planície Costeira do Rio Grande do Sul e de Santa Catarina contribuindo para o conhecimento da fauna de borboletas da Mata Atlântica. Foram compilados dados obtidos com amostragens realizadas através de duas técnicas de coleta (armadilha com isca atrativa e rede entomológica) nos anos de 2005 e 2011. Com um esforço amostral de 10.920 horas com armadilhas e de 360 horas-rede foram encontradas 225 espécies de borboletas nos dois ambientes, distribuídas em seis famílias e 19 subfamílias. Vinte e cinco espécies são registros novos ainda não publicados para o Rio Grande do Sul e 35 espécies são novos registros para a Mata Atlântica do Rio Grande do Sul, sendo seis Nymphalidae, dez Hesperiidae, doze Lycaenidae e sete Riodinidae. Os resultados gerados no presente estudo são fundamentais para o conhecimento e conservação dos táxons estudados bem como dos ambientes aos quais estão associados.

Fruit-feeding butterflies guide of subtropical Atlantic Forest and Araucaria Moist Forest in State of Rio Grande do Sul, Brazil

This study presents a compilation of fruit-feeding butterflies species for Rio Grande do Sul Atlantic Forest aiming to be a tool for identification of these lepidopterans from two phytophysiognomies of this biome. Samples were carried out for more than four years with entomological nets and bait traps techniques in areas of Subtropical Atlantic Forest (SAF) and Araucaria Moist Forest (AMF). Seventy-six butterfly species were recorded in this region of Atlantic Forest, 60 species for SAF and 53 for AMF. Fruit-feeding butterflies represent about 50% of the total species richness of the Nymphalidae recorded for the region, a value of the same order of those found for similar studies in tropical forests regions. Dasyophthalma rusina is a new record for Rio Grande do Sul.

Borboletas frugívoras (Lepidoptera: Nymphalidae) ocorrentes em um fragmento de Floresta Ombrófila Mista no Rio Grande do Sul, Brasil

O presente estudo tem como objetivo contribuir para o conhecimento das borboletas frugívoras em diferentes ambientes de um fragmento de Floresta Ombrófila Mista no município de São Francisco de Paula, região Nordeste do Rio Grande do Sul. As amostragens foram realizadas mensalmente entre março de 2008 e fevereiro de 2009 em duas transecções. Em cada transecção foram colocadas oito armadilhas atrativas fermentadas com banana e caldo de cana ao longo de três dias por ocasião amostral. Após um total de 5760 horas de amostragem foram registradas 30 espécies pertencentes a três subfamílias e seis tribos de borboletas frugívoras. Três espécies são novos registros para a Floresta Ombrófila Mista do Rio Grande do Sul: Prepona pylene pylene, Narope cyllastros e Opoptera sulcius, tendo esta última registro publicado para a região sudeste do estado.

Lepidoptera, Nymphalidae, Heliconiinae, Heliconius sara apseudes (Hübner, 1813): distribution extension

This work presents new records and extends the geographic distribution of Heliconius sara apseudes in the Atlantic Forest of the state of Rio Grande do Sul. Five new records were taken along butterfly inventories carried out between 2005 and 2010 in distinct phytophysiognomies at Rio Grande do Sul northeast region: Swamp Forest, Atlantic Forest stricto sensu and Araucaria Moist Forest. The fact that all registers occurred in well preserved habitats of the Atlantic Forest emphasizes the need of conservation of this biome in Rio Grande do Sul. 

Borboletas (Lepidoptera: Papilionoidea e Hesperioidea) ocorrentes em diferentes ambientes na Floresta Ombrófila Mista e nos Campos de Cima da Serra do Rio Grande do Sul, Brasil

Com o intuito de contribuir para o conhecimento das borboletas da Floresta Ombrófila Mista e Campos de Cima da Serra do Rio Grande do Sul foi elaborada uma listagem de espécies da assembléia de borboletas da Floresta Nacional de São Francisco de Paula e entorno. Foram realizadas saídas bimestrais de março de 2006 a maio de 2008 sendo selecionados seis ambientes: (i) mata nativa de Araucaria angustifolia, (ii) mata nativa mesclada com reflorestamento de Araucaria angustifolia, (iii) reflorestamento de Araucaria angustifolia de mata aberta, (iv) reflorestamento de Araucaria angustifolia de mata fechada, (v) reflorestamento de Pinus e (vi) campo de altitude nativo. Após 674 horas-rede de amostragem foram registradas 277 espécies e subespécies de borboletas, distribuídas em 9661 indivíduos, pertencentes a seis famílias, sendo destas 139 novos registros para esta região dos Campos de Cima da Serra, 13 novas ocorrências para o estado e seis espécies raras ou indicadoras de ambiente preservado.

Nymphalidae, Papilionidae e Pieridae (Lepidoptera: Papilionoidea) da Serra do Sudeste do Rio Grande do Sul, Brasil

Visando contribuir para conhecimento sistematizado da composição e distribuição da fauna de borboletas da região Sudeste do Rio Grande do Sul, entre abril de 2003 e janeiro de 2004, foram realizadas expedições para cinco locais na Serra do Sudeste. A composição de espécies de Nymphalidae, Papilionidae e Pieridae foi comparada aos registros existentes para as áreas adjacentes, na Encosta Sudeste e Litoral Sul, em Pelotas e seus arredores. No total de 289 horas-rede de amostragem, foram registrados 2.326 indivíduos e 81 espécies: 59 Nymphalidae, 12 Papilionidae e 10 Pieridae. Para a região adjacente, os trabalhos anteriores listam 138 espécies. Compilando-se ambas as fontes, obtém-se para a região Sudeste do Estado, 152 espécies: 110 Nymphalidae, 14 Papilionidae e 28 Pieridae. Do total de espécies, 14 (9%) ocorreram apenas na Serra do Sudeste e 71 (47%) em Pelotas e seus arredores. Os resultados apresentam a composição peculiar da lepidopterfauna da Serra Sudeste, e corroboram a importância biológica desta área do Estado.

Species composition and structure of Thysanoptera communities in different microhabitats at the Parque Estadual de Itapuã, Viamão, RS

Although thrips are known as inhabitants of flowers, they are also abundant and diverse in other microhabitats. There is an information gap concerning them, especially related to the native fauna in southern Brazil. The structure and composition of the thysanopteran community in different microhabitats was studied at the "Parque Estadual de Itapuã" (30° 22' S 51° 02' W), RS, southern Brazil. Between June 1999 and May 2001, branches (n = 1,274), flowers (n = 774), grass tussocks (n = 596) and leaf litter (n = 603) were sampled systematically in 20 points of four trails (T1 - Pedreira beach, T2 - Araçá beach, T3 - Lagoinha, and T4 - Grota hill). We found 2,197 adult thrips determined in 73 species in 41 genera, of which 37 could be nominated. Four families are represented, Thripidae, Phlaeothripidae, Heterothripidae and Merothripidae, with the first the most abundant (N = 1,599) and with the highest species richness (S = 32). The highest thrips abundance occurred in flowers N = 1,224 and the highest number of exclusive species occurred in the leaf litter (27). Frankliniella rodeos Moulton, 1933, Frankliniella gemina Bagnall, 1919 and Smicrothrips particula Hood, 1952 comprise 49.4% of the total sampled. Regarding T2, we obtained the highest abundance (N = 935) and highest species richness (S = 43). The composition of the faunas in each kind of environment proved very particular.

Thrips species (Insecta, Thysanoptera) inhabiting plants of the Parque Estadual de Itapuã, Viamão, Rio Grande do Sul state, Brazil

This study is a contribution to the knowledge of the thysanopterofauna of southern Brazil. From June 2003 to April 2004, seasonal field trips were conducted at the Parque Estadual de Itapuã (50º50'-51º05'W and 30º20'-30º27'S), in the county of Viamão, Rio Grande do Sul, to collect shoots with/without flowers of various plant species. The material was brought to the laboratory where the thrips were sorted. A total of 23 thrips species belonging to 15 genera and two families were obtained. Nine of the species resulted as new record for Rio Grande do Sul (*), and other two also for Brazil (**). The species sampled are as follows: Aneristothrips claripennis (Moulton, 1933)*, Aurantothrips orchidearum (Bondar, 1931)*, Ceratothripoides lagoenacollus (Moulton, 1933)*, Chaetanaphothrips orchidii (Moulton, 1907)*, Chaetisothrips striatus (Hood, 1935), Coremothrips pallidus Hood, 1925*, Craniothrips urichi Bagnall, 1915, Frankliniella bertelsi (De Santis, 1967), Frankliniella distinguenda Bagnall*, 1919, Frankliniella gardeniae Moulton, 1948*, Frankliniella gemina Bagnall, 1919, Frankliniella insularis (Franklin, 1908), Frankliniella oxyura Bagnall, 1919*, Frankliniella rodeos Moulton, 1933, Haplothrips fiebrigi Priesner, 1931, Hoodothrips lineatus (Hood, 1928), Microcephalothrips abdominalis (Crawford, 1910), Neohydatothrips denigratus (De Santis, 1966)**, Neohydatothrips fasciatus (Moulton, 1938)*, Neohydatothrips flavens (Moulton, 1941), Paraleucothrips minusculus Johansen, 1983**, Smicrothrips particula Hood, 1952, Thrips australis (Bagnall, 1915).

Reproductive parameters and longevity of Gryon gallardoi (Brethes) (Hymenoptera: Scelionidae) parasitizing Spartocera dentiventris (Berg) (Hemiptera: Coreidae) eggs

The fecundity, daily progeny and longevity of Gryon gallardoi (Brethes) (Hym.; Scelionidae) were determined under laboratory conditions, using Spartocera dentiventris (Berg) (Hem.; Coreidae) eggs as host. Nineteen G. gallardoi females and 34 males were reared at 25 +/- 1 degrees C, with a 12 h photophase, fed on a 10% aqueous honey solution and provided with 25-30 S. dentiventris eggs daily. The average pre-oviposition period was 1.3 +/- 0.35 days, although some females began laying from the day of emergence. On average, oviposition lasted for 10.1 +/- 1.74 days, reaching a peak on the second day, with 67.5 +/- 11.29 eggs laid. The post-oviposition period was short (2.4 +/- 0.48 days). G. gallardoi females lived significantly longer than males: 13.7 +/- 1.94 and 10.6 +/- 1.78 days, respectively. The overall sex ratio was 0.79. The results reported here on the reproductive capability of the species suggest it may have a good potential as an agent for the control of S. dentiventris.

Seasonal abundance and mortality of Oebalus poecilus (Dallas) (Hemiptera: Pentatomidae) in a hibernation refuge

Oebalus poecilus (Dallas) is an important pest affecting irrigated rice in Rio Grande do Sul, Brazil. It hibernates during the coldest months of the year in refuges such as bamboo litter. This study examined O. poecilus hibernation to determine the causes of mortality during this period. The study was conducted in a 140 m² bamboo plantation located in a rice-growing area in Eldorado do Sul County (30° 02’ S and 51° 23’ W), RS. During June 2000 to April 2002, 63 samples of litter were taken in weekly or fortnightly intervals, and the number of bugs recorded in the laboratory. The arrival at the hibernation site (bamboo litter) began in the first fortnight of March, and was completed in the beginning of May. O. poecilus left this refuge from middle October to the end of December. Parasitism by tachinid flies and Beauveria bassiana (Bals.) Vuill. fungus were the most important mortality factors.

Dispersal of the egg parasitoid Gryon gallardoi (Brethes) (Hymenoptera: Scelionidae) in tobacco crops

A mass marking-recapture experiment was carried out to study the dispersal of Gryon gallardoi (Brethes) (Hymenoptera: Scelionidae) in tobacco crops. Parasitoids emerged in the laboratory were marked with dye powder. Six separate field trials were conducted in Jan/Feb 2002 involving the simultaneous release of marked parasitoids. Dispersal was determined by the recapture of individuals in sets of sticky and Moericke traps arranged in three concentric circles arranged at 1.4 m intervals from the central point of release. Traps were checked 4, 8, 24, 28, 32 and 48 h after parasitoid release and weather data were recorded at 2-h intervals from 9 to 17 h at the site. Of the 699 marked parasitoids released, 91 were recaptured (13.02%). Fewer females were recaptured in the late afternoon, suggesting they are less active than males after dusk. G. gallardoi recaptures were not associated with average wind direction in any trials. After eight hours of release, recaptures occurred mostly in the traps farthest from the release point, suggesting that the experimental area was small in relation to the dispersal capacity of the parasitoid. Fitting a 4-h-after-release density-distance curve to a geometric model and considering a daily activity of 12 h, the female dispersal capacity was estimated to be at least 7.6 m/day. The values reported here must be considered as indicative of the potential for active dispersal under the particular experimental conditions of these trials. It is possible that G. gallardoi may disperse downwind much farther than the distance recorded in this study.

Effect of temperature on the development and viability of Gryon gallardoi (Brethes) (Hymenoptera: Scelionidae) parasitizing Spartocera dentiventris (Berg) (Hemiptera: Coreidae) eggs

The development and viability of Gryon gallardoi (Brethes) (Hym.: Scelionidae) in Spartocera dentiventris (Berg) (Hem.: Coreidae) eggs were studied under four temperatures: 15, 20, 25, and 30 +/- 1 degree C, with a 12-h photophase. No parasitoid developed at 15 degrees C. Otherwise, viability reached 98.8% without varying significantly over the temperature range tested. The duration of development for males and females was inversely proportional to the temperature increase, varying respectively from 46.2 +/- 0.13 and 47.1 +/- 0.11 days (20 degrees C) to 13.3 +/- 0.07 and 13.4 +/- 0.06 days (30 degrees C). Males developed faster than females. The values estimated for the lowest thermic thresholds of development and the thermic constants were 15.5 degrees C and 185.19 DD for males and 15.6 degrees C and 192.31 DD for females, respectively. Given the average weather conditions in Porto Alegre, RS (30 degrees 01' S and 51 degrees 13' W), Brazil, G. gallardoi could annually produce 8.54 and 8.07 generations of males and females, respectively. The low rates of parasitism observed in the field during the first generation of its host may be due to the small number of G. gallardoi generations in this period.

Characterization of the imaginal reproductive diapause of Oebalus poecilus (Dallas) (Hemiptera: Pentatomidae)

The state of development of the internal reproductive organs of male and female Oebalus poecilus (Dallas) as well as the body fat amount in the abdominal cavity during hibernation, of individuals sampled in bamboo litter in Eldorado do Sul (30º02'S and 51°23'W), RS, Brazil was investigated. Females and males showed the abdominal cavity filled with body fat in the beginning of the hibernation phase. The decrease in fat reserve level occurred from August on for males and from October on for females. Ovaries and testis doubled in length and tripled in width from immature to the reproductive phase. Male sexual maturation occurred in the hibernation sites while for females it occurred later on outside of the sites. Reproductive organ immaturity and abdominal body fat hypertrophy characterized the diapause of O. poecilus.

Oviposition behaviour of Gryon gallardoi (Hym.; Scelionidae) on eggs of Spartocera dentiventris (Hem.; Coreidae)

The oviposition behaviour of Gryon gallardoi (Hymenoptera; Scelionidae) on Spartocera dentiventris (Hemiptera; Coreidae) host eggs was investigated in the laboratory. Masses of 12 non-parasitized freshly laid (less than 24 h old) eggs were exposed to 2-5 days old mated females with previous oviposition experience (n = 10). Behaviour was observed for 2 h under the stereomicroscope. The eggs were Then kept individually at 25 degrees +/- 1 degree C/12 h photophase till hatching. The mean number of parasitized eggs was 7.8 +/- 0.81 (mean +/- SE). Five distinct kinds of behaviour were observed: drumming with antennae on the eggs, ovipositor insertion, egg marking, walking and resting. On average, ovipositor insertion was not followed by marking 4.3 +/- 0.76 times per female. In nearly all of these events, parasitism was unsuccessful. Walking and resting were observed less frequently than the other behaviours (1.6 +/- 0.56 and 2.1 +/- 0.48 times/female, respectively). Superparasitism occurred on average 3.6 +/- 0.88 times per egg mass, with 2.7 +/- 0.57 eggs being superparasitized. Among these, on average 87.4 +/- 5.37% led to successful development of an adult parasitoid. The average time spent on the each kind of oviposition behaviour was 1.5 +/- 0.57 min for drumming, 3.9 +/- 0.56 min for ovipositor insertion and 0.4 +/- 0.06 min for marking. There was no significant variation on the duration of each behaviour as the parasitoid progressed in parasitizing an egg mass. Ovipositor insertion almost always (87.58%) occurred in the longitudinal extremities of the egg. In average 31.1 +/- 7.21% of the individual emerging per egg mass were males, the larger proportion of males originating from the 2nd oviposition. The results show a range of oviposition behaviours common to the Scelionidae family. Egg marking behaviour was a good indicator of the effective oviposition by females. Superparasitism is only partially avoided, but its occurrence does not imply a failure of parasitoid emergence. The sex ratio is skewed towards females, and most males come from the first ovipositions.

Movement pattern of Spartocera dentiventris (Berg) (Hemiptera: Coreidae) in an experimental crop of Nicotiana tabacum L. (Solanaceae)

In the present work we investigated the movement pattern of Spartocera (= Corecoris) dentiventris (Berg) (Hemiptera: Coreidae) adults through the mark-release-recapture method in an experimental tobacco crop (Nicotiana tabacum L., Solanaceae) in Porto Alegre, RS, Brazil. We marked 217 specimens from August 1999 to April 2000. Females moved 2.94 +/- 0.198 times and males 1.46 +/- 0.171 times among host plants. The number of movements per capture was 0.53 +/- 0.03 for females and 0.54 +/- 0.06 for males. Newly recruited adults took 12.75 +/- 0.919 days to leave their original plant, females moved 9.87 +/- 0.711 m and males 9.16 +/- 1.29 m in this first movement. We estimate that females move an average of 26.22 m and males 13.89 m during their permanence in the area.

Natural enemies of the gall-maker Eugeniamyia dispar (Diptera, Cecidomyiidae): predatory ants and parasitoids

Natural enemies of the gall maker Eugeniamyia dispar (Diptera: Cecidomyiidae) were studied on the urban area of Porto Alegre, RS, Brazil from October 1993 to March 1996. Galls and associated arthropods were followed weekly in the field on individual host plants (Eugenia uniflora, Myrtaceae) and also in the laboratory. Three species of ants attacked the galls, the most common being Pseudomyrmex sp. A proportion of galls was parasitised by Rileya sp. (Eurytomidae). The adults of this solitary ectoparasitoid were also attacked by the ants and fell prey to spider webs.

Life history of the gall-maker Eugeniamyia dispar Maia, Mendonça-Jr. & Romanowski, 1996 (Diptera, Cecidomyiidae)

The development of the galls of the midge Eugeniamyia dispar Maia, Mendonça-Jr. & Romanowski, 1996 (Diptera: Cecidomyiidae) was monitored weekly on its host plant, Eugenia uniflora (Myrtaceae). The work was carried out in the urban area of Porto Alegre, RS, Brazil, from October 1993 to September 1995. Galls were collected from the field and raised in the laboratory to obtain adults. The females oviposit on young leaves of the host plant, with the first instar larvae inducing the gall, which is unilocular. The last instar larvae drop to the soil to pupate and later emerge as adults. The galls occur from late August to early June, when young leaves of the host can be found, with populations peaking during the summer. So far this species is only known from the two southernmost states of Brazil (RS and SC).