ABSTRACT. Eugl ossine bees (Apidae) frem Atlantic Forest sites: abundance, richness, and bi ological aspects. Co llection data of Euglossinae males from Parque Estadual do Rio Doce (PERD) and Viçosa, both areas w ith remnants of Atlantic Rain Forest (Mata Atlântica) in Minas Gerais state, Brazil are presented. Comparisons made among three fragments with different sizes and states of di sturbance fi'om Viçosa showed difterences in abundance of most common spec ies and apparently, Eu/aema nigrita Lepeletir, 1841 can be an useful indicator of disturbed sites . Some populations of euglossine bees seems to be restrict to a forest fragment, there being few or no tlow of individuais OI' species of one fi'agment to another, even when they are only I km apal1. 15 species of euglossines were sampled in PERD, and the most abundant was Eu/aema cingu/ata (Fabricius, 1804). At Viçosa, 10 species were samp led, E. nigrita was the predominant one. Methyl sali cylate attracted no males at both sites, in spite of large numbers of species and individuais sampled using this bait in other regions. The majority ofspecies and indi viduais were collected in the rainy season. Only 0,58% ofsampled males carried orchid pollinia (Cataselum Richard, Cycnoches Lindley and Coryanthes Hook) on their bodies. Emergence data of [our species 01' Eug/ossa Latreille, 1802 reared from trap nests suggest lhat sex ralio in Euglossini is not a constant w ithin the lribe. A li sl of 57 eugloss ine spec ies now known to occur in Mata Atlântica are oftered. KEY WORDS. Apidae, Euglossini, Atlantic Forest, conservation, bioindicator Há 35 anos machos de Euglossini vêm sendo coletados com auxílio de iscas contendo compostos aromáticos similares aos encontrados em flores de algumas Orchidaceae e de outras plantas e em alguns fungos. Foi LOPES (1963) o primeiro a verificar que machos dessas abelhas podiam ser atraídos e capturados utilizando-se armadi lhas contendo compostos aromáticos como iscas. Isto, associado a sua grande diversificação ecológica e taxonômica, abundância e importância em alguns ecossistemas, faz desses insetos candidatos a indicadores das qualidades ambientais de áreas naturais ou de conservação (BROWN 1991).

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ABSTRACT. Sex allocation and sex-dependent selection for body size in Trypoxylon rogenhoferi Kohl (Hymenoptera, Sphecidae). Two populations of the wasp Trypoxylon rogenhoferi Kohl, 1884 from São Carlos and Luís Antônio, State of São Paulo, Brazil, were observed and sampled from May 1999 to February 2001 using trap-nests. This mass-provisioning wasp was used to test some aspects of optimal sex allocation theory. Both populations fit all the predictions of the models of Green and Brockmann and Grafen. Maternal provisions determined the size of each offspring, and females allocated wellstocked brood cells to daughters, the sex that benefits most being large. This strategy resulted in a difference in size between the sexes. In São Carlos, female weight at emergence was 1.18 times that of males, in Luís Antônio this value was 1.13. The brood cell volume was correlated with both wing length and weight at emergence in both sexes, and the chance that a given brood cell contained a male offspring decreased with increased brood cell volume. In T. rogenhoferi female body size was related to fitness. Larger females were able to collect more mass of spiders per day, the spiders they captured were heavier, and they provisioned more brood cells per day. They also produced larger daughters. For males, no relationship between body size and fitness was found, but the data were scarce. Since the patterns of provisioning were variable among different females in both study sites, it is possible that the females not follow a unique strategy for sex allocation. The sex ratio and/ or investment ratio in the São Carlos population was female-biased and in Luís Antônio, male-biased. In spite of the influence of trap-nests diameters on male production in Luís Antônio, there is some evidence that in São Carlos population the local availability of prey and/or lower rate of parasitism may be major forces in determining the observed sex ratio, but further studies are necessary to verify such hypothesis.

ABSTRACT. ASPECTS DF BIDLOGV DF EUPLUSIA VIOUCEA (BLANCHARO) (HVMENDPTE. RA, klDAÉ, EUGWSSINI). Nests of orchid bee Euplusia violacea (Blanchard, 1840) col\eted''íó trap-nests and in lhe wood of a construction in Viçosa, Minas Gerais (20"45'30"S, 42°52'05"W), Brazil, were studied under laboratory condictions. Some aspects of lhe biology of lhese bees were observed, such as sex-ratio, development time, longevity and olhers. Some aspects of lhe bebavior of E. violacia were also studied. KEY WORDS. Apoidea, Euglossini, Eup/usia vio/acea, euglossine nest, behavior A despeito do grande interesse despertado pelas abelhas da tribo Euglossini, poucos dados a respeito da biologia desses insetos são conhecidos. Uma revisão sobre o assunto é feita por ZUCCHI et aI. (1969).A maioria dos trabalhos realizados limitam-se ao levantamento de espécies com auxílio de iscas odoríficas que permitem coletar machos

The Neotropical stingless bee Melipona quadrifasciata Lepeletier was evaluated for pollinating tomatoes (variety Rodas; long-life hybrid) in greenhouses under plastic and with a hydroponic system and "organic concepts" in Minas Gerais State, Brazil. Flowers not pollinated did not set any fruit. Pollination by bees plus manual pollination did not differ from either bee or manual pollination. Maximum fruit diameter, fruit height, and roundness (quotient between maximum fruit diameter and fruit height) were not significantly different between treatments, but fruit visited by M. quadrifasciata had 10.8% less seeds (dry mass) than manual pollination. This apparently low efficiency of M. quadrifasciata pollination was attributed to the overlap of only 30 min between highest bee foraging activity and highest flower stigma receptivity. Thus, it was concluded that M. quadrifasciata is a feasible pollinator of greenhouse tomatoes because of 1) the observed increase in fruit quality with lower mechanical injury than traditional manual pollination, 2) no significant decrease in fruit size, and 3) high price of such product in the market. Some considerations for sustainable use of M. quadrifasciata as greenhouse pollinator are presented. Although techniques for keeping captive colonies of M. quadrifasciata are currently available, the sole current method for acquiring new colonies is removing them from the forest, and if demand was created for large numbers of colonies for commercial use, techniques for captive rearing must be developed to prevent serious declines in wild populations.

ABSTRACT. Notes on the sociality and nesting biology of Trypoxylon (Trypoxylon) asuncicola Strand, 1910 (Hymenoptera, Sphecidae). Twenty-two nests of Trypoxylon asuncicola were sampled in Viçosa, State of Minas Gerais, Brazil, in January 2000 and the occupants' behavior of three nests was registered in 2h of direct observation. 528 brood cells were excavated (24±13.84 SD cells per nest), 129 were reused cells, some of them for seven times (meconium deposit count). The mean number of total cells, mean number of open and closed cells, parasitism rate and mean number of reused cells per nest were similar between old and new nests. Parasitism rate and cell reuse were associated with the number of building cells in the nest, but nest aggregate in the sampled area may play some role in the parasitism rate. Brachymeria sp. (Chalcididae) was the most important agent of brood mortality (80%). Other parasites were Melittobia sp. (Eulophidae) (17%) and a species of Icheumonidae (3%). The number of closed cells with immature individuals per nest was 4±4.2SD (N=17) and the mean reproductivity per female was 3±2.4SD (N=5). New nests produced more offspring (0 a 35%) than old nests (0 to 11%). Females and males can be found resting in the nest but copula or guarding behavior by the male was not observed. There is some evidence that in the sampled area the switch of nests by females is great and agonistic behavior between a nest owner and a visitor was not evident. Females were larger (3.9±0.4SD mm) than males (3.1±0.3SD mm) (measured as forewing length). The secondary sex ratio was 1.26 (±0.07 SE) in favor of females, which was not different from 1:1 ratio. The majority (97%) of the sampled larvae of T. asuncicola showed diapause. Some (5.1%) 'anomalous cells' were found.

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