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Melipona bicolor schencki occurs in southern Brazil and at high elevations in southeastern Brazil. It has potential for use in meliponiculture but this stingless bee species is vulnerable to extinction and we have little knowledge about its ecology. In order to gather essential information for species conservation and management, we made a study of seasonal flight activities in its natural environment. We sampled bees entering the nests with pollen, nectar/water and resin/mud, in five colonies during each season. In parallel, we analyzed the influence of hour of the day and meteorological factors on flight activity. Flights were most intense during spring and summer, with daily mean estimates of 2,100 and 2,333 flights respectively, while in fall and winter the daily flight estimate was reduced to 612 and 1,104 flights, respectively. Nectar and water were the most frequently-collected resources, followed by pollen and building materials. This preference occurred in all seasons, but with variations in intensity. During spring, daily flight activity lasted over 14 hours; this period was reduced in the other seasons, reaching eight hours in winter. Meteorological factors were associated with 40.2% of the variation in flight and resource collection activity. Apparently, other factors that we did not measure, such as colony needs and availability of floral resources, also strongly influence the intensity of resource collection. Melipona bicolor schencki ocorre no Sul e em regiões de altitude elevada no Sudeste do Brasil. Encontra-se vulnerável a extinção no Rio Grande do Sul e possui potencial para meliponicultura, entretanto o conhecimento de sua ecologia é escasso. Desenvolveu-se o estudo sazonal das atividades de vôo de colônias em ambiente natural, com vistas a subsidiar ações conservacionistas e manejo. Amostrou-se o ingresso de pólen, néctar/água e resina/barro em cinco colônias, durante o período de atividades externas, em cada estação do ano. Analisou-se também a influência do horário e de fatores meteorológicos sobre o vôo. Os vôos foram similarmente mais intensos durante a primavera e verão, com estimativa diária de 2100 e 2333, enquanto no outono e inverno reduziram-se respectivamente para 612 e 1104. O transporte de néctar/água foi maior, seguido de cargas de pólen e de materiais de construção. Esta situação ocorreu similarmente nas quatro estações, porém com variações de intensidade. A amplitude diária de vôo foi de 14 horas na primavera, reduzindo-se nas demais estações e atingindo 8 horas no inverno. Os fatores meteorológicos exerceram influência de 40,2% no vôo das abelhas. Este resultado indica que outros fatores, não mensurados neste estudo, como as necessidades das colônias determinadas por fatores fisiológicos e a disponibilidade de recursos florais, exercem forte influência sobre a intensidade de coleta de recursos.

It is unclear whether stingless bees in the genus Melipona (Hymenoptera, Apidae, Meliponini) can reli- ably encode the distance to a food source through recruitment sounds produced inside the nest, in part because the sound features correlated with distance also vary with food quality. We therefore trained marked foragers of two species, Melipona mandacaia and M. bicolor, to feeders at different distances and to different sucrose concentrations at the same distance. In both species, foragers successfully recruited to a rich 2.5-m food source and produced pulsed recruitment sounds in which pulse duration was significantly and positively correlated with distance to the rich food source. When returning from poorer food sources (0.6-1.5 m), foragers of both species decreased sound production, producing shorter sound pulses and longer sound interpulses than they did for 2.5 m food located at the same distance. Thus the temporal structure of M. mandacaia and M. bicolor recruitment sounds varies with distance and food quality. However, nestmates were not recruited by performances for poorer food sources (0.6-1.5 m), whose sucrose concentration was sufficiently low to affect recruitment sounds. Surprisingly, the interphase (the time between behavioral phases that communicate location) also in- creases with decreasing food quality in the closely related honeybees (Apis), suggesting a potential homology in the effect of food quality on the recruitment systems of Apis and Melipona. We explore the evolutionary implications of these similarities.

Young virgin queens of the stingless bee Melipona bicolor have been shown to produce wax like workers. The small, white to transparent flakes of wax of the queens protrude from the intersegmental space and cover the anterior part of the tergite cuticle, in a way similar to that in workers. This points to the presence of wax glands in the queens. However, workers produce wax from glands located at the fourth to seventh tergites whereas queens secrete wax from the epidermal gland at the third tergite only. Analysis of the queen-produced wax showed that it contains the same substances as the worker-produced wax with minor differences in composition. The wax consists chiefly of the long-chain esters triacontanyl acetate and octacosanyl acetate, smaller amounts of linear C21 to C31 alkanes and alkenes, and still smaller quantities of linear aldehydes and isobutyrate esters. Analysis of wax from wax deposits and wax constructs showed the same composition. Wax from M. bicolor is similar to that of other stingless bees in containing the range of linear long-chain alkenes and alkanes and different from that of Apis bees which contains a more complex mixture, less hydrocarbons and more long chain esters.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:20:23Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:44:49Z : No. of bitstreams: 1 2-s2.0-0036337154.pdf: 2204295 bytes, checksum: 169ece704d6f06a797f183123aef89bd (MD5) Made available in DSpace on 2014-05-27T11:20:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-01-01 The present paper reports morphological features of the testes reabsorption in adult male of Melipona bicolor bicolor. The ultrastructural features of the degenerating sperm cells and cyst cells are described. It is suggested that the material of the reabsorbed testes may serve as nutritional source for the adult male. Departamento de Biologia Inst. de Biociencias de Rio Claro UNESP, Av. 24 A, no 1515, CEP 13506-900, Rio Claro-SP Departamento de Biologia Inst. de Biociencias de Rio Claro UNESP, Av. 24 A, no 1515, CEP 13506-900, Rio Claro-SP

As in many other stingless bees, Melipona bicolor bicolor Lepeletier (Apidae: Meliponinae) workers lay two morphologically distinct types of eggs: slender ones that have a typical patterned chorion, and larger ones that lack this pattern. In this paper we report on the relation between egg morphology and the behaviour of the workers that lay such eggs. In most cases, the laying of each of these egg types is accompanied by a unique sequence of behaviours. After a worker has laid the unpatterned type of egg, she generally leaves the cell, giving the queen the possibility of eating this egg. In the case of the patterned egg type, the worker usually closes the cell immediately after her egg laying. When worker egg laying occurs right after a series of regurgitations, it stops the queen from ovipositing. When, instead, a worker lays an egg after queen oviposition, the cell contains two eggs. This study also revealed cases in which workers laid slender, patterned eggs without closing the cell, and other cases where workers laid large, spherical, unpatterned eggs and instantly closed the cell. Experiments in which worker eggs, destined to be eaten by the queen, were protected by covering the cell artificially with a piece of wax showed that some of these eggs developed into larvae, although they were occasionally relatively small. The occurrence of a range of combinations of egg-laying behaviours and egg morphologies in M. b. bicolor workers is discussed from the perspective of worker egg laying in other stingless bees.

Flight activity of Melipona bicolor bicolor, coming from Cunha (23º05'S, 44º55'W), Atlantic Forest, was studied in ten colonies, and in two periods: from July to September 1993 and from August to September 1995. The colonies were grouped in weak, medium and strong, according to the diameter of the combs, which can provide a good idea of the number of cells built. 855 observations were accomplished for 5 minutes, every half-hour, from 8 to 18 hours. The total number of bees that entered and left the hive and the number of bees that arrived with mud, pollen and resin, besides the number that went out with debris in that period were counted. It was also registered the temperature and the relative humidity of the air. The total external activity, as well as pollen collection, was maximum in the first hours of the morning, mainly in strong colonies. Weak colonies moved their maximum activity approximately to 12 hours. Pollen collection declined gradually, while mud and resin collection rose; removal of debris was greater in the beginning of the morning and in the end of the afternoon. Flight activity increased as relative humidity of the air rose, being optimum for strong colonies in the range between 80%-89%, and for the weakest colonies between 70%-79%. The minimum temperature observed for exit of the bees was 11ºC, with optimum temperatures ranging between 17ºC and 22ºC. The results showed that the general state of the colony influences the different strategies of food collection and that these bees should be adapted to environments of high relative humidity as the Atlantic forest.

Dans une zone protegee de la foret ombrophile cotiere pres de Sao Paulo, on a preleve sur une annee des echantillons de pollen et de miel dans deux colonies de Melipona bicolor et deux de M quadrifasciata (abeilles sans aiguillon) et dans deux colonies d'abeilles africanisees, Apis mellifera, et on a fait des analyses polliniques de ces echantillons. Des pelotes de pollen ont ete recoltees au moins deux fois par mois i) sur des ouvrieres capturees devant le trou de vol (Melipona), ii) dans des trappes a pollen (Apis). En outre des echantillons de pollen et de miel ont ete preleves chaque mois dans les pots de reserve nouvellement remplis des colonies de Melipona et dans les nouveaux rayons des colonies d'Apis (dans deux cadrons suspendus le mois precedent). Les echantillons ont ete traites et les preparations polliniques realisees selon Vorwohl (1977) et Louveaux et al (1970). Pour les echantillons de pollen, on a estime les pourcentages relatifs en poids et en volume des types polliniques (Vorwohl, 1977; Biesmeijer et al, 1992). Le recouvrement des niches alimentaires (NO) a ete calcule d'apres Colwell et Futuyama (1971). Pour mesurer l'impact potentiel de l'abeille africanisee on a defini un indice de competition (PC Am ), qui est le produit du recouvrement des niches et de la recolte globale des abeilles africanisees. Dans la foret ombrophile de Boraceia les colonies de melipones ont recolte du pollen et du nectar tout au long de l'annee. La recolte de pollen (nombre de pots a pollen nouvellement remplis) a ete maximale en novembre (figs 1 et 2), tandis que la recolte de miel (nouveaux pots a miel) a presente deux maximums, l'un en juillet et l'autre en decembre (fig 3). Aout et decembre ont ete les mois ou les colonies d'abeilles africanisees ont engrange le plus de pollen et de miel, respectivement (fig 4). Dans les echantillons de pollen et de miel des colonies de Melipona, les Myrtacees et les Melastomatacees ont domine presque toute l'annee (tableau II et III; fig 5) ; cela confirme les etudes d'autres auteurs realisees dans des habitats principalement influences par l'homme. L'abeille africanisee a utilise un large spectre de plantes nourricieres (tableau I), caracterise par un renouvellement presque mensuel des principales ressources (tableaux II et III). Les differences entre les echantillons provenant des ouvrieres et ceux issus des pots a pollen s'expliquent par les faits suivants : i) par butinage intense, toutes les ouvrieres rentrant a la colonie avec des pelotes ne peuvent pas etre capturees devant le trou de vol, c'est pourquoi, dans ces echantillons, les plantes qui fleurissent en masse et peu longtemps sont sous-representees ; ii) selon Sommeijer et De Bruijn (1994), les abeilles Melipona ont une forte tendance a fermer les pots a pollen; apres une forte rentree de pollen il est possible que le pollen rapporte soit traite sans passer par les pots a pollen, si bien que les pollens qui ne sont disponibles que peu de temps et en petites quantites sont a peine presents dans les pots a pollen. La quantite absolue du pollen preleve sur les butineuses ne depend pas seulement de l'offre pollinique mais aussi des conditions meteorologiques les jours ou les prelevements sont faits. Le nombre de pots a pollen nouvellement remplis nous semble plus approprie pour evaluer la quantite de pollen rapporte a la colonie. Le recouvrement des niches est plus important pour les deux especes de melipones entre elles (moyenne annuelle 0,66 et 0,82 pour les echantillons de pollen provenant respectivement des butineuses et des pots a pollen et 0,68 pour les echantillons de miel) qu'entre les melipones et l'abeille mellifere (0,27 et 0,44 pour M bicolor, 0,23 et 0,5 pour M quadrifasciata

International audience; Melipona bicolor schencki is currently considered a threatened stingless bee in southern Brazil, and studies about its ecology may provide new insights to enable its conservation. This study evaluated the seasonal variability in the sex/caste proportion, numbers of combs and brood cells, and spatial distribution of the individuals present in emerging combs in five polygynous colonies of M. bicolor schencki for 1 year. Throughout the year, the colonies showed similar variations. Individual combs exhibited a higher number of brood cells in spring and summer, although there was no variation in the number of combs over the four seasons. Workers (79.7 %), queens (15.6 %), and drones (4.7 %) were produced in all months sampled. Analysis of spatial distribution indicated no clear predominance of a specific sex or caste in a specific comb area, contrary to other species of Melipona.

Stingless bee colonies typically consist of one single-mated mother queen and her worker offspring. The stinglessbee Melipona bicolor(Hymenoptera: Apidae) shows facultative polygyny, which makes this species particularly suit-ablefortestingtheoreticalexpectationsconcerningsocialbehavior.Inthisstudy,weinvestigatedthesocialstructureandgeneticrelatednessamongworkersfromeightnaturalandsixmanipulatedcoloniesofM.bicoloroveraperiodofone year. The populations of M. bicolorcontained monogynous and polygynous colonies. The estimated genetic re-latedness among workers from monogynous and polygynous colonies was 0.75 0.12 and 0.53 0.16 (mean SEM), respectively. Although the parental genotypes had significant effects on genetic relatedness in monogynousandpolygynouscolonies,polygynymarkedlydecreasedtherelatednessamongnestmateworkers.Ourfindingsalsodemonstrate that polygyny in M. bicolormay arise from the adoption of related or unrelated queens. Key words: Melipona , microsatellites, polygyny, queen number, social structure.Received: August 6, 2010; Accepted: December 21, 2010.

At present a complete mtDNA sequence has been reported for only two hymenopterans, the Old World honey bee, Apis mellifera and the sawfly Perga condei. Among the bee group, the tribe Meliponini (stingless bees) has some distinction due to its Pantropical distribution, great number of species and large importance as main pollinators in several ecosystems, including the Brazilian rain forest. However few molecular studies have been conducted on this group of bees and few sequence data from mitochondrial genomes have been described. In this project, we PCR amplified and sequenced 78% of the mitochondrial genome of the stingless bee Melipona bicolor (Apidae, Meliponini). The sequenced region contains all of the 13 mitochondrial protein-coding genes, 18 of 22 tRNA genes, and both rRNA genes (one of them was partially sequenced). We also report the genome organization (gene content and order), gene translation, genetic code, and other molecular features, such as base frequencies, codon usage, gene initiation and termination. We compare these characteristics of M. bicolor to those of the mitochondrial genome of A. mellifera and other insects. A highly biased A+T content is a typical characteristic of the A. mellifera mitochondrial genome and it was even more extreme in that of M. bicolor. Length and compositional differences between M. bicolor and A. mellifera genes were detected and the gene order was compared. Eleven tRNA gene translocations were observed between these two species. This latter finding was surprising, considering the taxonomic proximity of these two bee tribes. The tRNA Lys gene translocation was investigated within Meliponini and showed high conservation across the Pantropical range of the tribe.

In the present study we compare genetic characteristics (allele diversity and observed heterozygosity) of microsatellite loci, from three stingless bee species (Plebeia remota Holmberg, Partamona mulata Moure In Camargo and Partamona helleri Friese), amplified by using heterospecific primers originally designed for Melipona bicolor Lepeletier and Scaptotrigona postica Latreille. We analyzed 360 individuals of P. remota from 72 nests, 58 individuals of P. mulata from 58 nests, and 47 individuals of P. helleri from 47 nests. The three species studied showed low level of polymorphism for the loci amplified with primers derived from M. bicolor. However, for the loci amplified with primers derived from S. postica, only P. remota presented low level of polymorphism.

The focus of this paper is the process for brood production known as the Provisioning and Oviposition Process (POP), and particularly the individual behavior observed in the facultatively polygy- nous stingless bee Melipona bicolor. Following individually marked bees revealed that ovarian development is correlated with individual behavior differences. While most of the eggs laid by workers are consumed by the queen (trophic eggs), workers contribute significantly in male production with reproductive eggs, illustrating the reproductive conflict at the individual level. From an evolutionary outlook, "benefactor" behaviors may evolve if workers conserve the "hope" of reproduction. This indicates that an important function of trophic eggs is to keep the ovaries active. It is also possible that ovary development represents an internal factor promoting division of labor: reproductive workers are specialized or elite bees with low response thresholds and high activity levels that restrain the participation of other workers. stingless bees / division of labor / POP / Melipona bicolor / reproductive competition / Apidae

Mitochondrial gene rearrangement events, especially involving tRNA genes, have been described more frequently as more complete mitochondrial genome sequences are becoming available. In the present work, we analyzed mitochondrial tRNA gene rearrangements between two bee species belonging to the tribes Apini and Meliponini within the "corbiculate Apidae". Eleven tRNA genes are in different genome positions or strands. The molecular events responsible for each translocation are explained. Considering the high number of rearrangements observed, the data presented here contradict the general rule of high gene order conservation among closely related organisms, and also represent a powerful molecular tool to help solve questions about phylogeny and evolution in bees.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:08Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:29:04Z : No. of bitstreams: 1 2-s2.0-1542655544.pdf: 110911 bytes, checksum: b9896dadc3a674cf57d6b1867bf7ab0e (MD5) Made available in DSpace on 2014-05-27T11:21:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-09-01 The mandibular gland secretions of newly emerged, nurse and forager workers, virgin and physogastric queens and males of Melipona bicolor were analyzed by gas chromatography-mass spectrometry. The secretion is composed of a blend of hydrocarbons, alcohols, esters, and acids. The secretion is caste-sex specific and also differs with the tasks performed by the workers and the physiological reproductive condition of the queens. Departamento de Biologia Instituto de Biociências Universidade Estadual Paulista, Av. 24A, 1515, 13506-900 Rio Claro - SP School of Chemistry and Physics Lennard-Jones Laboratories Keele University, Staffordshire, ST5 5BG Departamento de Biologia Instituto de Biociências Universidade Estadual Paulista, Av. 24A, 1515, 13506-900 Rio Claro - SP

The mandibular gland in Melipona bicolor workers and queens was studied by scanning and transmission electron microscopy. There is no difference in the gland anatomy between the castes, but the transmission electron microscopy showed variation of the cellular ultrastructure according to the secretory phase of the gland in both castes. Smooth endoplasmic reticulum was abundant in the secretory cells of physogastric queens, indicating that these cells produce lipid secretion that is stored in granules with multi-lamellar bodies. Mitochondrial variations during the cell secretory cycle indicates their participation in the lipid synthesis. After secretion, release in the reservoir lumen through the collecting canals, the secretory cells contain many myelinic bodies, indicative of cellular regression.

The presence of spermatozoa in vesicles in the cytoplasm of the epithelial cells that constitute the spermathecal wall of Melipona bicolor queen (Meliponini) is discussed in relation to the organ structure. The epithelial wall is lined by an apparently continuous cuticle in the luminal surface that should be a non-transposable barrier to the luminal spermatozoa. However, some spermatozoa were seen crossing the cuticle through interruptions that was first interpreted as sectioning defects. Nevertheless, the sperm cells in well-structured cytoplasmic vesicles, bound by membranes and sometimes associated to multivesicular bodies, as well as cytoplasmic structures representative of intracellular digestion and the occurrence of the phenomenon in two of the three spermathecae studied, suggest a real spermiophagic hole in the spermathecal epithelial cells.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:43:52Z No. of bitstreams: 1 S0073-47212001000200025.pdf: 408215 bytes, checksum: 653ef987ea24b6ba95a65beca64ec0fc (MD5) Made available in DSpace on 2013-08-22T18:43:52Z (GMT). No. of bitstreams: 1 S0073-47212001000200025.pdf: 408215 bytes, checksum: 653ef987ea24b6ba95a65beca64ec0fc (MD5) Previous issue date: 2001-11-27 Made available in DSpace on 2013-09-30T19:31:49Z (GMT). No. of bitstreams: 2 S0073-47212001000200025.pdf: 408215 bytes, checksum: 653ef987ea24b6ba95a65beca64ec0fc (MD5) S0073-47212001000200025.pdf.txt: 15928 bytes, checksum: 742c7050ebb5b738c9fd79a97fc441bc (MD5) Previous issue date: 2001-11-27 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:41Z No. of bitstreams: 2 S0073-47212001000200025.pdf: 408215 bytes, checksum: 653ef987ea24b6ba95a65beca64ec0fc (MD5) S0073-47212001000200025.pdf.txt: 15928 bytes, checksum: 742c7050ebb5b738c9fd79a97fc441bc (MD5) Made available in DSpace on 2014-05-20T15:08:41Z (GMT). No. of bitstreams: 2 S0073-47212001000200025.pdf: 408215 bytes, checksum: 653ef987ea24b6ba95a65beca64ec0fc (MD5) S0073-47212001000200025.pdf.txt: 15928 bytes, checksum: 742c7050ebb5b738c9fd79a97fc441bc (MD5) Previous issue date: 2001-11-27 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The morphology of the cyst cells in Apis mellifera Linné, 1758, Scaptotrigona postica Latreille, 1804, and Melipona bicolor bicolor Lepeletier, 1836 testis, as well as the average number of spermatic cells are reported. The data indicates a supporting and nourrishing role of the cyst cells to the developing cystocytes. The counts of immature spermatozoa in the cysts show an average of 202.8 ± 21.2 spermatozoa for A. mellifera, 117.4 ± 8.68 for S. postica and 88.8 ± 15.57 for M. bicolor, which predict the occurrence of 8 mitotic cycles in the cystocytes of A. mellifera and 7 in the meliponines, considering that only one spermatozoom originates of each final spermatogonium. Universidade Estadual Paulista Instituto de Biociências Departamento de Biologia Universidade Estadual Paulista Instituto de Biociências Departamento de Biologia

La theorie de la selection de la parentele predit qu'un individu peut parvenir a l'adequation adaptative (fitness) au moyen de la reproduction indirecte en aidant l'elevage des descendants d'un parent et l'on s'attend a ce que cette aide soit dirigee de preference vers les individus qui partagent un fort degre de parente avec l'acteur. M. bicolor est la seule espece fortement eusociale connue qui presente une polygynie facultative de longue duree. Nous avons teste la tendance eventuelle des ouvrieres a faire la distinction entre des reines physogastriques qui leur sont plus ou moins apparentees. Une colonie possedant deux reines physogastriques, qui s'etaient accouplees quatre mois plus tot et etaient probablement sœurs, a ete suivie pendant cinq jours et cinq nuits de suite du point de vue des processus d'approvisionnement et de ponte (POPs). Nous avons enregistre les types de comportement suivants d'ouvrieres marquees individuellement: aprovisionnement de la cellule avant la ponte, ponte avant et apres la ponte de la reine, obturation de la cellule apres la ponte de la reine. Afin d'evaluer l'eventuelle preference de ces ouvrieres marquees pour l'une ou l'autre reine, nous avons enregistre le nombre total de comportement effectues par chaque ouvriere vis-a-vis de chaque reine. La note 1 a ete attribuee a la reine lorsque le comportement n'etait effectue que vis-a-vis d'une reine, et la note un demi a chaque reine, lorsque les deux reines etaient presentes au cours du POP. Seules les ouvrieres que nous avons vu participer a quatre POPs au moins ont ete retenues pour l'analyse (figure 1). La possibilite que les ouvrieres aient pu etre stimulees par la presence d'une reine et n'aient pas ete inhibees par la presence de l'autre a ete prise en consideration. Aussi dans une autre analyse, seuls les POPs au cours desquels une seule reine etait presente, ont ete retenus et nous avons a nouveau teste l'eventuelle preference des ouvrieres (figure 2). Dans les deux cas, les ouvrieres ayant reparti leurs activites au hasard sur les cellules frequentees par les reines, nous en concluons qu'elles n'ont pas de preference pour l'une ou l'autre des reines. Par ailleurs, nous avons retire de la colonie utilisee pour l'experience 1 l'une des reines et l'avons remplace par deux reines physogastriques non apparentees, prelevees dans d'autres colonies. Nous avons repete le suivi des comportements et refait la meme analyse de donnees; la encore nous n'avons trouve aucune preference des ouvrieres, que la reine leur soit apparentee ou non (figures 3 et 4). Dans une troisieme experience nous avons recherche si les gardiennes a l'entree de la colonie rejetaient les reines physogastriques etrangeres. Pour cela huit reines physogastriques ont ete retirees de leur colonie et immediatement placees a l'entree d'une colonie choisie au hasard et possedant une reine. L'introduction a ete consideree comme reussie lorsqu'au moins trois heures plus tard la reine pouvait etre observee sur le rayon apparemment en bonne sante. Toutes les reines introduites ont ete acceptees. Implications sur le plan de l'evolution: si la possibilite existe de discriminer les reines d'apres des informations genetiques, elle n'est pas utilisee par les ouvrieres presentes dans la colonie.