Floral resources collected by four native bees species in southern Mexico

Abstract

Melissopalynological analysis of 14 honey samples of Tetragonisca angustula (two), Scaptotrigona mexicana (six), Melipona beecheii (three) and Melipona solani (three) from Soconusco region in Chiapas, Mexico was performed. A total of 79 taxa were identified, being Asteraceae, Euphorbiaceae, Fabaceae, Melostomataceae and Rubiaceae the predominant pollen types. Melissopalynological analysis reported a monofloral composition for Melipona beecheii honeys, where the most predominant pollen type was Fabaceae (54.2%). T. angustula, Scaptotrigona mexicana and Melipona solani honey samples were multifloral and predominant pollen types were Asteraceae, Euphorbiaceae, Fabaceae, Melastomataceae and Solanaceae. The most frequent polliniferous pollen type were Asteraceae, Bernardia interrupta, Euphorbia heterophyla and Miconia. Shannon–Wiener diversity index (H′) for Melipona beecheii 2016 (2.21) and Melipona solani 2017 (1.64) were lower meanwhile honeys of Melipona beecheii 2017, S. mexicana 2017, Melipona solani 2016 and T. angustula 2017 were considered as fairly diverse, because they visited a wider range of plant species, by preferring shrub and wild strata such as: Asteraceae, Euphorbia, Euphorbiaceae, Miconia and Mimosa. Our results showed that the foraging behaviour of these bee species is polylectic, as no taxa was found to be more than 70% of the counted grains. Since the study of the collection of meliponine flower resources in the southern region of Mexico have not been studied yet, it is not possible to analyse the foraging behaviour, the use of resources and the management of these species in this region.     

Partitioning of pollen resources by two stingless bee species in the north Bahia,Brazil

Analysing the pollen stored by stingless bees allows identification of the diversity of flowering plants visited by these bees while collecting resources during a given period. However, few studies have focused on investigating the sharing of resources between species of native bees that coexist in transitional plant formations, which support conservation efforts and increase colony productivity. This study aims to describe the partitioning of pollen resources among colonies of two species of stingless bees in the state of the Bahia (Brazil) through the analysis of stored pollen. The study was conducted in neighbouring vegetation zones of the relevant species Melipona quadrifasciata anthidioides and Melipona scutellaris by collecting monthly pollen samples stored by three colonies of each species over one year. The collected samples were treated using the acetolysis technique, and the partitioning of pollen resources between the two species was investigated through quali-quantitative analysis of the treated pollen. The results show that among the 16 pollen types belonging to a particular species or group identified in the Melipona quadrifasciata anthidioides samples and the 18 identified in the Melipona scutellaris samples, 13 were shared by both species. The two most common pollen types stored by both species were from Mimosa arenosa (Fabaceae, Mimosoidae) and Eucalyptus sp. (Myrtaceae). These results demonstrate the niche similarity of pollen pasture between these two species and suggest that conservation efforts for these bee species should focus on the plant families most visited by bees.     

Floral resources and risk of exposure to pesticides for Melipona quadrifasciata anthidioides Lepeletier 1836 in a Cerrado of São Paulo (Brazil)

Honey and bee bread samples from storage pots of Melipona quadrifasciata anthidioides were collected monthly from April 2015 to May 2016 in the Mogi Guaçu Biological Reserve (22º 10? S, 47º 11? W). The flora in the site is characteristic of the Atlantic Forest with preserved areas of savanna-like vegetation surrounded by commercial forests, orchards and various crops of exotic and native plants. Samples were analysed with the use of melissopalynological methodology and 46 pollen types from 38 genera and 30 families were identified in 25 honey samples. Fabaceae, Asteraceae, Myrtaceae, Sapindaceae showed the greatest pollen richness in honey. Predominant nectariferous pollen types were Anadenanthera, Cordia, Eucalyptus, Mimosa scabrella, Schefflera, Sida, Serjania and Vernonia. Twenty-eight types of pollen from 21 genera and 19 families were identified in 22 bee bread samples. Fabaceae, Asteraceae and Myrtaceae showed the highest pollen richness. Anadenanthera, Cecropia, Eucalyptus, Melastomataceae, Mimosa scabrella, Mimosa verrucosa and Myrcia were the most frequent polliniferous pollen types. Principal component analysis (PCA) demonstrated that honey and pollen samples formed two main groups of similarity, mainly due to Eucalyptus’ nectar and pollen of Melastomataceae, respectively. Melipona quadrifasciata anthidioides collected nectar and pollen from the preserved areas as well as in the secondary and ‘ruderal’ vegetation and in cultivated forests/fields, suggesting their importance as pollinators both of native flora and exotic species. The use of trophic resources of plants grown with pesticides is a concern for the conservation of these species of bee and should be better studied.     

Comparative floral preferences in nectar and pollen foraging by Scaptotrigona postica (Latreille 1807) in two different biomes in São Paulo (Brazil)

To describe the trophic resources used by Scaptotrigona postica, honey and bee bread samples were taken monthly from May 2015 to December 2016 at two different localities. Fontes do Ipiranga State Park (PEFI), an urban remnant of the Atlantic Forest, and the Mogi Guaçu Biological Reserve (RBMG), in the Cerrado. Two colonies were kept in each site. Samples were analysed with the melissopalynological method in order to calculate the relative frequencies. Principal component analysis was used to compare the similarity between the samples and to examine the influence of quantitative and qualitative data on the ordination of the pollen types. Similarity tests were performed to compare the pollen spectra of the bee bread and honey samples between the study sites and seasons. Hence, 69 and 61 pollen types were identified in 33 honey and 29 bee bread samples. The main families in honey were Asteraceae, Euphorbiaceae and Fabaceae; in bee bread Fabaceae, Myrtaceae and Sapindaceae were the main families for both localities, followed by Asteraceae, Euphorbiaceae and Solanaceae at the RBMG. The results showed that the species maintains its floral preferences regardless of the biome in which it occurs. Also, demonstrates that the bees make use of nectariferous and polliniferous sources available in the preserved areas as well as in its surroundings. There is a risk of pesticides exposure caused by the use of trophic resources of cultivated plants by this bee. This points to the need for further studies.     

Pollen types from colonies of Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) established in a coffee plantation

Melipona scutellaris is a eusocial bee with potential to be used as a crop pollinator. This study aimed to identify pollen types used by Melipona scutellaris through the analysis of pollen loads and honey samples in colonies established in a coffee plantation. We analysed 117 pollen loads and pollen content of 15 honey samples. In the pollen loads, we identified 40 pollen types. Poincianella pyramidalis, Coffea arabica, Commelina villosa, Mimosa tenuiflora, Myrcia, Senna macranthera, Solanum and Syagrus coronata stood out as predominant pollen. We found a negative correlation between the abundances of the pollen types Coffea arabica and Mimosa tenuiflora during coffee flowering. In the honey samples, we recorded 33 pollen types. Eucalyptus and Machaerium occurred in frequencies of between 16 and 45%. Although Melipona scutellaris gathers resources from several plant species, its diet is based on a relatively narrow subset of plants.     

Pollen analysis of honeys of Melipona (Michmelia) seminigra merrillae and Melipona (Melikerria) interrupta (Hymenoptera: Apidae) bred in Central Amazon,Brazil

The pollen present in honey in colonies of Melipona seminigra merrillae and Melipona interrupta bred in Manaus was analysed. Between August and October 2012, honey samples were collected from the Sucupira meliponary, located in Manaus, Amazonas, Brazil. We identified a total of 70 pollen types belonging to 35 botanical families. In the samples from Melipona seminigra merrillae, the most represented pollen types were: Miconia-type (Melastomataceae) was the dominant pollen (DP) in August (51.19%), September (76.83%) and October (58.33%); Triplaris-type (Polygonaceae) was an accessory pollen (AP) in August (20.5%); and the remaining pollen types were classified as isolated pollen (IP), with Talisia macrophylla (Sapindaceae) exhibiting the highest percentage in August (12.92%). For Melipona interrupta, the most frequent pollen types were as follows: Miconia-type was the DP in August (59.33%) and October (61.33%) and an AP in September (37.5%); and Triplaris-type was an AP in August (35.83%), September (34.16%) and October (23.33%). The diversity of pollen types was not significantly different between the bees in the months evaluated. However, there was a large significant niche overlap in the months studied, August (O_ik = 0.95), October (O_ik = 0.89) and September (O_ik = 0.69), revealing that of the 70 pollen types found in the samples, 22 were shared by the two bee species in large proportions, 28 were exploited exclusively by Melipona seminigra merrillae and 20 were collected only by Melipona interrupta.     

Major plants foraged by bees for honey production in Ghana: mapping of bee floral sources for the development of the apicultural industry

Abstract

Honey is increasingly being used as a food supplement and to treat various diseases and disorders in Ghana. Information on floral nectar preferences of foraging honeybees is, therefore, imperative to increase production to keep pace with demand. However, in Ghana, these floral nectar preferences are yet to be investigated and identified. This study was conducted to determine bee forage sources in the three main agro-ecological honey-producing zones of Ghana. Forty-eight unblended honey samples sourced from beekeepers were analysed. Pollen spectra of the honey samples revealed 27 different pollen types of which eight were identified to family level, while 15 and four were at the level of genus and species, respectively. The results also showed that, in general, 48% of the analysed samples were unifloral honeys with the most important pollen types coming from Sapotaceae/Meliaceae, Anacardiaceae and Burkea africana. Combretaceae, Sapotaceae/Meliaceae and Anacardiaceae, as well as Lannea-type and Burkea africana were found to be the most frequent (with occurrence greater than 50%) sources of nectar utilised by bees to produce honey. The predominant pollen sources of the honeys in the three main apicultural zones of the country were Sapotaceae/Meliaceae and Anacardiaceae (Forest zone), Sapotaceae/Meliaceae and Lannea-type (Savannah–Forest transition zone) and Sapotaceae/Meliaceae, Anacardiaceae and Gynandropsis gynandra (Savannah zones). Identification of the major bee floral sources can be used as a guide by beekeepers in the location of their apiaries as well as reforesting disturbed sites with these plants to act as sources of bee forage.     

Apicultural pollen from the Andean region of Chubut (Argentinean Patagonia)

An analysis of pollen loads of Apis mellifera was performed in order to identify the pollen sources that support the hives in the Andean region of Chubut. During the apicultural period (from 9 September 2010 to 12 March 2011), pollen loads were collected every fortnight in a selected apiary located in a transition area between the sub-Antarctic forests and the Patagonian steppe. Forty-six pollen types belonging to 26 plant families were found in the pollen spectrum of pollen loads, of which the most diverse were Asteraceae (11 types) and Fabaceae (six types). Families with major biomass contribution were Asteraceae (49%), Fabaceae (10%), Salicaceae (10%), Rhamnaceae (7%), Rosaceae (7%) and Brassicaceae (4%). Thirty-one per cent of the identified pollen belonged to the native flora. The major contribution of indigenous species occurred in late spring. Mutisia spp., Discaria type, Senecio spp., Adesmia spp. and Maytenus spp. were the most collected native taxa. Most plants providing pollen to the beehive are also nectariferous resources in the Andean region of Chubut. The protein content of the collected pollen ranged from 7.78% to 32.48%. The most collected types had protein content between 13.09% and 30.93%.     

Pollen analysis of honeys from Caatinga vegetation of the state of Bahia,Brazil

Based on pollen analysis, 17 honey samples collected in the Caatinga area from Nova Soure city were classified by botanical origin to identify the most important floral sources. Most of the honey samples were obtained in August and September. A total of 73 pollen types were identified belonging to 30 families, 64 genera and 30 species. The families best represented by their number of pollen types were Mimosaceae (11), Caesalpiniaceae (9), Rubiaceae and Fabaceae (5 each). Predominant pollen types were: Mimosa arenosa in four samples, M. sensitiva and M. tenuiflora in one sample. Pollen from Mimosa ursina was registered for the first time in the pollen spectrum of the Caatinga vegetation. The correspondence analysis showed a similarity among the honey samples based on pollen composition. The high representation of pollen from native species such as Chamaecrista nictitans, C. ramosa, C. swainsonii and Copaifera martii (Caesalpiniaceae); Aeschynomene martii and Zornia sericea (Fabaceae); Herissantia tiubae (Malvaceae); Mimosa arenosa, M. quadrivalvis, M. sensitiva, M. tenuiflora, M. ursina, Piptadenia moniliformis and Plathymenia reticulata (Mimosaceae), and Ziziphus joazeiro (Rhamnaceae) supports the origin of these honeys from Caatinga vegetation.     

Floral sources used by the orchid bee Euglossa cordata (Linnaeus, 1758) (Apidae: Euglossini) in an urban area of south-eastern Brazil

Although orchid bees (Apidae: Euglossini) are known as key pollinators in tropical ecosystems, knowledge of their floral sources is still scarce, especially for those species commonly found in urban environments. We aimed to identify the pollen, nectar and resin sources used by the widespread species Euglossa cordata in an urban area in south-eastern Brazil. The residual pollen from 81 brood cells of nine nests reactivated between October 2013 and December 2014 was acetolysed and analysed. A total of 50 pollen types belonging to 20 botanical families were identified in the samples. Pollen sources included species from seven families; five of them were plants with poricidal anthers (Bixaceae, Commelinaceae, Fabaceae, Melastomataceae and Solanaceae). The mass-flowering trees Handroanthus chrysotrichus and H. heptaphyllus (Bignoniaceae) are firstly reported as important pollen sources to an orchid bee species. Nectar was collected primarily from plants with long, tubular corolla as Acanthaceae, Apocynaceae, Bignoniaceae and Convolvulaceae. The vine species Dalechampia stipulacea (Euphorbiaceae) acted as a floral resin source. All pollen sources consisted of native plants whereas some exotic plant species were visited for nectar collection. Although nesting in an area encompassed by a high proportion of invasive plant species, Euglossa cordata females preferred to visit native plants to gather floral resources.     

Pollen analysis of Apis dorsata Fabricius honeys in Bankura and Paschim Medinipur districts,West Bengal

One-hundred-and-five species corresponding to 38 families were identified through pollen analyses of 53 Apis dorsata honeys collected from Bankura and Paschim Medinipur districts, West Bengal. The families most frequently encountered were Fabaceae, Arecaceae, Asteraceae and Myrtaceae. Fabaceae had the greatest representation in number of pollen types (18 types), followed by Asteraceae (nine types), Cucurbitaceae (seven types), Lamiaceae and Myrtaceae (each with six types) and Malvaceae and Rutaceae (each with five types). Most of the honey samples correspond to class I. The presence of dominant pollen was detected in 18 samples. The predominant pollen types were Borassus flabellifer, Sesamum indicum (during summer), Eucalyptus globulus (during late autumn), Brassica nigra, Eucalyptus globulus (during winter) and Borassus flabellifer and Lannea coromandelica (during spring). The unifloral honeys obtained mostly during late autumn and winter were dominated by Eucalyptus globulus type. In monsoon and autumn unifloral honeys containing predominant pollen types (> 45%) were not found. However, according to frequency distribution the pollen types represented as very frequent were Peltophorum pterocarpum, Tridax procumbens (in monsoon) and Acacia auriculiformis, Cocos nucifera, Eucalyptus globulus, Tridax procumbens and Ziziphus mauritiana (in autumn). The seasonal diversity of pollen types obtained was at a maximum during spring (36 types) and minimum during late autumn (14 types). Seasonal variation in the number of pollen types per sample range from 5.86 ± 1.87 (during late autumn) to 6.86 ± 1.95 (during autumn) and exhibit low correlation (r = 0.31) with floral diversity. The diversity of pollen types per unifloral honey sample remains lower than multifloral honeys.     

Arecaceae potential for production of monofloral bee pollen

Bees often collect pollen from plants that are near their colonies or apiaries. Arecaceae are characterised by having species that flower throughout the year and produce large quantities of pollen. Pollen grains of Arecaceae have two main forms, namely monosulcate and trichotomosulcate. The study area is located in the coastal region of the state of Sergipe, Brazil, where large amounts of bee pollen are produced by Apis mellifera. This study aims to evaluate how Arecaceae contribute to the production of monofloral bee pollen. Samples of bee pollen loads were collected each month for two years (totalling 24 samples), acetolysed, and mounted on permanent slides. At least 500 grains of pollen were counted for each sample, the data was analysed, and figures were made using the Tilia software. The pollen grains of Cocos nucifera were present in 23 samples (96%), and concentrations of this pollen type varied between 1.1 and 46.8% (but were commonly above 20%). The concentration of Arecaceae pollen grains is the result of the large-scale production of coconuts along the coastline. However, the presence of other pollen types, such as Mimosa arenosa, Mimosa pudica, Mikania and Myrcia, compliments the diets of bees in the region. The results show that even when in low frequency, Cocos nucifera pollen grains represent a large proportion of pollen content compared with other pollen types, because of the large size of Arecaceae pollen grains.     

Floral Preference of Melipona eburnea Friese (Hymenoptera: Apidae) in a Colombian Andean Region

Melipona eburnea Friese is a stingless bee kept in some regions of Colombia, where it is reported to be vulnerable to extinction due to habitat disturbance. To contribute to raising conservation strategies, the aim of this study was to identify the floral preferences of this species using melissopalynological analysis. A total of 31 pollen pot samples and 37 honey samples were taken from March 2009 through March 2010 from four colonies in Fusagasuga, Colombia. We found 92 pollen types: 17 from pollen pot samples, 39 from honey samples (indicating the sources of nectar), and 36 in both types of samples. The most frequent pollen types in the pollen pot samples were Myrcia type (100%), Eucalyptus globulus (96.9%), and Fraxinus uhdei (96.9%). The most frequent pollen types in honey samples were E. globulus (97.4%) and Myrcia type (94.9%). The pollen types corresponded mainly to native plants (68%), trees (44.5%), plants whose sexual system is hermaphroditic (56.5%), and plants with inflorescences (76.2%). The most frequent shapes of the flowers were brush-like (type Myrtaceae) and dish-like (type Asteraceae), and the preferred flower colors were white or cream (52.2%). In general, we found that M. eburnea showed a strong preference for trees of the family Myrtaceae to obtain nectar and pollen, including native and introduced species. Some other families are contributing significantly, such as Melastomataceae for pollen collection and Asteraceae for nectar. These results highlight the key plant species for the diet of M. eburnea.     

Seasonal variation of collected pollen loads of honeybees (Apis mellifera L. anatoliaca)

Pollen collected by honeybees foraging in the region of Bursa, Turkey was analysed for a whole year. Pollen loads were collected from the hives of Apis mellifera anatoliaca once a week and were classified by colour. Forty‐one taxa were identified from the pollen analyses of the loads and 14 of these had percentages higher than 1%. Only 2.05% of the total pollen could not have been identified. Dominant taxa include; Brassicaceae (11.19%), Helianthus annuus L. (10.84%), Cichorioideae (8.93%) Salix spp. (7.99%), Rosaceae (7.37%), Centaurea spp. (7.56%), Papaver spp. (7.41%), Knautia spp. (6.99%), Fabaceae (6.01%), Asteraceae (5.73%), Xanthium spp. (2.65%), Chrozophora spp. (2.45%), Plantago spp. (1.56%) and Acer spp. (1.54%) representing 88.23% of the total. Distinct variations in plant usage are seen through the year with initial use of Rosaceae, Salix, and to a lesser extent Brassicaeae. As these groups finish flowering the bees move onto Helianthus annuus, Centaurea through the summer followed by Asteraceae in the late summer and Fabaceae in the autumn. There is a strong reliance on crop species for pollen forage but a number of indigenous species are also seen within the samples. The most productive period for collecting various pollen types, and the ideal period to determine pollen preferences of honey bees was June‐August.     

First pollen record for Ancyloscelis apiformes (Apidae: Emphorini) in Central Amazon

Abstract

The first pollen study for the solitary bee Ancyloscelis apiformes (Emphorini) in a nest aggregation in the Central Amazon was made in October 2012 at the Sucupira apiary in east Manaus, Amazonas, at 03° 00? 05″ S, 59° 51? 05″ W. A total of 15 samples/nests (N1–N15) were analysed, including intact pollen loads (stored inside the nest) and post-emergence residues, which were acetolysed and mounted in glycerine gelatin. From each sample, 500 pollen grains were counted to determine the pollen frequencies and diversity (H′) and evenness (J′) indices. The most representative pollen types were Bonamia ferruginea (N1 = 95.6% and N2 = 96.00%) and the Ipomoea (N3 = 96.40%), both of which belong to the Convolvulaceae. In addition, Byrsonima crispa (N10 = 93.40%) and Malpighia glabra (N7 = 90.20% and N9 = 97.60%), representatives of the Malpighiaceae, were classified as temporary specialisation events with frequencies above 90%. In this study, A. apiformes, which is considered an oligolectic bee species, presented a polylectic tendency since it collected large percentages of pollen types from plants in distinct families that were not phylogenetically related.     

Spatial predictability and resource specialization of bees (Hymenoptera: Apoidea) at a superabundant, widespread resource

For reciprocal specialization (coevolution) to occur among floral visitors and their host plants the interactions must be temporally and spatially persistent. However, studies repeatedly have shown that species composition and relative abundance of floral visitors vary dramatically at all spatial and temporal scales. We test the hypothesis that, on average, pollen specialist bee species occur more predictably at their floral hosts than pollen generalist bee species. Taxonomic floral specialization reaches its extreme among species of solitary, pollen-collecting bees, yet few studies have considered how pollen specialization by floral visitors influences their spatial constancy. We test this hypothesis using an unusually diverse bee guild that visits creosote bush (Larrea tridentatd), the most widespread, dominant plant of the warm deserts of North America. Twenty-two strict pollen specialist and 80 + generalist bee species visit Larrea for its floral resources. The sites we sampled were separated by 0.5 to > 1450 km, and spanned three distinct deserts and four vegetation zones. We found that species of Larrea pollen specialist bees occurred at more sites and tended to be more abundant than generalists. Surprisingly, spatial turnover was high for both pollen specialist and generalist bee species at all distances, and species composition of samples from sites 1–5 km apart varied as much as repeat samples made at single sites. Nevertheless, the pattern of bee species turnover was not haphazard. As distance among sites increased faunal similarity of sites decreased. Faunal similarities among sites within 250 km of each other were generally greater than if randomly distributed over all sites (the null model). No single ecological category of species (widespread, localized, Larrea pollen specialist, floral generalist) accounted for this spatial predictability. Evidently, concordant local distribution patterns of many ecologically diverse species contribute to the non-random spatial pattern. The ecological dominance of creosote bush does not confer obvious ecological advantages to its specialist floral visitors. Spatial turnover is comparable to that found for bee guilds from other biogeographic regions of the world and is not therefore limited to those bee species that inhabit highly seasonal climates, such as deserts. Philopatry and differences in bloom predictability among sites are probably more important causes for spatial turnover of bee species than are interspecific competition for nest sites or floral resources.     

Botanical affinity of pollen harvested by Apis mellifera L. in a semi-arid area from Bahia,Brazil

We analysed the botanical composition of pollen harvested by Apis mellifera L. in the Canudos Biological Station, Bahia, Brazil, and the influence of climatic factors on pollen sample composition was assessed. Forty-six pollen types were identified belonging to species occurring in the study area. The family Leguminosae was of significant importance amongst the samples, represented by ten pollen types. Diodia radula, Rhaphiodon echinus, and Mimosa misera pollen types occurred most constantly among the samples. We observed that isolated pollen class characterises samples analysed. It was also observed that pollen type richness is directly linked to rainfall, reflecting the strong influence of this climatic parameter on flowering intensity, and thus on the ability of the bees to obtain food resources.     

Palynological characterisation of sedra honeys (Ziziphus lotus) produced in Algeria

Abstract

A melissopalynological study was carried out on 46 samples of Ziziphus lotus honey from Laghouat and Djelfa region (central Algeria). The number of pollen types identified per honey sample ranges between nine and 39 with a mean of 24. These correspond to 52 botanical families with 79 different pollen types in the whole samples. Asteraceae and Fabaceae families were present in all the samples where as Apiaceae, Brassicaceae and Nitrariaceae (Peganum harmala) were identified in more than 90%. Other plant families as Boraginaceae, Cistaceae, Myrtaceae, Oleaceae, Salicaceae or Urticaceae were identified in more than 50% of the samples but frequently as minor pollen. Ziziphus lotus pollen had a mean content of 68.9% (with a range of 45.3% to 93.4%). The secondary pollen types were Ononis natrix, Peganum harmala, Brassica napus, Echium and Olea europaea. Regarding the important pollen it is highlighted the presence Lotus t., Eucalyptus, Pimpinella anisum t., Trifolium t., Eryngium campestre t., Centaurea t., Galega officinalis t., Citrus or Scrophularia t. The sedra honeys of the studied region are characterised by their high content in pollen grains with a mean content of 188 403 grains/10 g. The presence of some pollen types in the pollen spectra of honeys such as Peganum harmala, Thapsia garganica, Launaea, Muscari comosum, Carthamus or Limonium bonduellei together several Asteraceae as Centaurea, Taraxacum, Carduus, Artemisia and Matricaria was proposed as geographical markers of this honey type.     

Melissopalynology in an area of Atlantic Forest (northeast region,Brazil)

Apis mellifera is a bee that was introduced to Brazil and has adapted very well to the climate conditions and vast diversity of plants that exist in the country. In the northeast region of Brazil, beekeepers make use of the association between bees and plants by selling various bee products, notably honey. One way to identify species visited by bees in an area is by the pollen in its products. Based on this, 16 samples of honey were analysed, which were collected over a period of two years and obtained from an apiary in the Atlantic Forest biome in the municipality of Entre Rios (Bahia). In addition, climatic data (precipitation and temperature) of the region were obtained for the months sampled. The average temperature of the region during the collection months varied from 22 to 28 °C. The highest precipitation recorded in the region was 133.7 mm³ and the lowest was 0.3 mm³. Seventy pollen types were found. The family Fabaceae was notable, with ten pollen types, of which Mimosa pudica was the most important with a high frequency of occurrence and distribution. The Eucalyptus (Myrtaceae) pollen type also had a high frequency of occurrence and distribution. In addition, pollen types corresponding to species that supply nectar to bees were identified, which contributes to the large diversity of bee plants for Apis mellifera in the study area.     

Niche differentiation in nectar-collecting stingless bees: the influence of morphology, floral choice and interference competition

1. Dozens of social bee species, most of them stingless bees, occur sympatrically in the tropics. The proximate mechanisms through which they partition their resources are, apart from aggressive interactions between Trigona species, not well studied. In the work reported here, niche differentiation at patch level was studied, using two species of Melipona that occur sympatrically in the Central Pacific part of Costa Rica. Foragers of Melipona beecheii are known to collect more concentrated nectar than do Melipona fasciata foragers, even from the same plant species. This observation raises the question of what mechanism leads to such partitioning of nectar resources? To address this question, the roles of bee morphology, floral preferences, and interference competition in partitioning of nectar sources were studied. 2. It was shown experimentally that the feeding rate of both species was highest at 60% nectar concentration. Melipona fasciata preferred 60–70% concentrations to less concentrated solutions, whereas M. beecheii ignored 20% solutions and visited the other solutions equally often. Both species preferred sucrose to glucose and fructose. Melipona beecheii, with a yellowish coloured body, preferred sunny patches, whereas M. fasciata, with a dark brown body, preferred shady patches. Interference competition between the species occurred when they visited the same sugar-water feeder: M. fasciata was dominant over M. beecheii. 3. The nectar foraging strategies of the two species can be summarised as follows: M. beecheii is able to visit sunlit patches, due to its lighter body colour, and is thus able to collect nectar of optimal or near optimal sugar concentration (40–65%). Individuals do not actively choose nectar with a high concentration of sugar, but the average sugar concentration in bee-collected nectar will typically be high in sunlit patches. Melipona fasciata, on the other hand, avoids sunlit patches, but actively chooses the richest nectar in shady patches and tries to dominate such patches. Thus, niche differentiation occurs according to the radiation regime at flower patches, and interference competition will occur rarely under natural conditions. The role of similar mechanisms in other closely related stingless bees is discussed.