Plebeia

Abstract: Information on flower visits by species of stingless bees in natural and modified communities in the Neotropics have mostly indicated generalized use of floral resources (Absy et al. 1984, Engel & Dingemans-Bakels 1980, Iwama & Melhem 1979, Roubik 1979). However, estimates of foraging diversity have also indicated that only a few floral resources were intensively used at any one time, and stingless bee species in a community differed somewhat in their choice of these resources (Imperatriz-Fonseca et al. 1984, Kleinert-Giovannini & ImperatrizFonseca 1987, Ramalho et al. 1985, Roubik et al. 1986, Sommeijer et al. 1983). For these bee species, polylecty is probably an outcome of continuous activity, while floral choice at any one time may be related to behavioural and ecological factors. This preliminary study was performed to evaluate the contribution of pollen analysis in the study of ethoecological features involved in flower choice by eusocial bees. Materials and methods. The study was performed at the gardens of the Biosciences Institute of Sao Paulo University (IBUSP), in the urban region of Sao Paulo city (230 33' S, 460 43' W), which have diverse native and foreign species of plants, including a small semi-deciduous forest of native species, covering approximately 10 hectares. The eusocial bee species studied were: Apis mellifera Linne (referred to as Am), Trigona spinipes Fabricius (Ts), Trigona (Tetragonisca) angustula Latreille (Ta), Paratrigona subnuda Moure (Ps), Plebeia droryana Friese (Pd), Plebeia emerina Friese (Pe), Plebeia remota Holmberg (Pr), Plebeia (Friesella) schrottkyi Friese (Fs), Melipona quadrifasciata quadrifasciata Lepeletier (Mq), Melipona marginata Lepeletier (Mm) and Plebeia saiqui Friese (Pq).

Abstract: The present work attempts to establish probable evolutionary trends and relationships among the various groups of stingless bees, and in doing so to provide a new classification for the subfamily Meliponinae. This study concludes that the stingless bees had their center of origin and dispersion in Africa. This is based on the wide acceptance of continental drift, the primitiveness of several African Meliponinae, and the discovery of a European stingless bee fossil from the late Eocene, which shows that the Meliponinae were not restricted to America at that time.Parallel evolution seems to have taken place between the African genera and several groups of stingless bees from other continents. For instance, resemblances between Cleptotrigona and Lestrimelitta; between Dactylurina and Tetragona; between Meliponula and Melipona; and between Meliplebeia and Plebeia, result from parallelisms or convergences.The new classification here presented demostrates and defends the recognition of certain groups as genera and subgenera, and the relegation of other names to synonymy.

Abstract: Nous avons etudie la teneur en eau (MC) du miel de diverses especes sympatriques d'abeilles sans aiguillon et l'avons compare a celle du miel d'Apis mellifera produit dans le meme environnement tropical a Trinidad et Tobago. Sept cent dix sept echantillons de miel ont ete preleves dans des reserves operculees et non operculees dans des colonies de Melipona favosa, Melipona trinitatis, Plebeia tobagoensis, Trigona nigra et A. mellifera. La valeur moyenne la plus forte de MC dans les pots opercules (42,0 %) a ete trouvee chez P. tobagoensis et la plus faible (20,2 %) chez A. mellifera. Les autres valeurs de la MC etaient de 36,2 % pour T. nigra, de 31,2 % pour M. favosa et de 32,2 % pour M. trinitatis. La variation entre colonies de la meme espece sur le meme site d'echantillonnage a ete faible, mais le miel de M. favosa de Trinidad avait une MC plus forte (35,1 %) que celui de Tobago (30,2 %). Pour les grandes series provenant des colonies de M. favosa en aout 1998, la teneur en eau du miel dans les pots non opercules etait beaucoup plus forte (35,0 %) que dans les pots opercules (28,4 %). Nos resultats confirment que le miel des abeilles sans aiguillon possede une teneur en eau generalement beaucoup plus forte que celui d'A. mellifera. Le phenomene du miel aqueux chez les abeilles sans aiguillon peut etre lie a l'environnement tropical humide, ou il est difficile de produire un miel fortement deshydrate. Le probleme de la deterioration facile du miel aqueux pourrait etre surmonte si les abeilles ajoutaient des enzymes ou d'autres substances ayant une activite antibiotique, ce qui corroborerait les allegations d'activite medicinale de ces miels.