DOI: 10.13102/sociobiology.v67i4.5841Sociobiology 67(4): 554-565 (December, 2020) Open access journal: http://periodicos.uefs.br/ojs/index.php/sociobiology ISSN: 0361-6525 Introduction Bee populations are at risk in several parts of the world. The removal of native vegetation to expand agricultural areas has been one of the factors with a significant contribution to the fragmentation and reduction of natural and semi-natural habitats. Deforestation reduces the diversity of plants used as food resources, nesting substrates, and sources of materials necessary for bee nesting (Freitas et al., 2009; Kevan, 2018). Knowledge about food plants used by bees is important to support habitat restoration programs and the conservation of bee populations, as well as to subsidize beekeeping (Maia- Silva et al., 2020). In addition, it is necessary to produce a scientific knowledge basis capable of subsidizing friendly agricultural practices to pollinators. Therefore, efforts must be made to identify the resources necessary for the persistence of bee populations in these habitats. Abstract In this study, we investigated the group of floral resources that support bee populations in a savanna area and how bee species use these food resources, with an emphasis on the breadth and overlap of trophic niches. The interactions between 75 bee species and 62 plant species were recorded on a Brazilian savanna area. The bee species explored a diverse set of plant species, but concentrated the collection of resources in a few species. The trophic niche breadth of the eusocial bees ranged from 0.77 to 2.59, while in non-eusocial bees the variation was from 0.35 to 1.99. The distribution of the samples over a long period favored a robust characterization of the food niche of the bee populations. Byrsonima sericea, Serjania faveolata, and Stigmaphyllon paralias were the plant species with the highest number of links with bees. In general, the trophic niche overlap was low, with 75% of pairs of bee species having a niche overlap (NO) less than 0.33. Only four pairs showed high overlap (NO>0.70) and all cases were related to the exploitation of floral resources provided by B. sericea, a key resource for the maintenance of the local bee fauna, an oil and pollen provider. Sociobiology An international journal on social insects CO Santos1, CML Aguiar2, CF Martins3, EB Santana4, F França2, E Melo2, GMM Santos2 Article History Edited by Denise Alves, USP, Brazil Received 09 September 2020 Initial acceptance 10 November 2020 Final acceptance 08 December 2020 Publication date 28 December 2020 Keywords Anthophila, Malpighiaceae, trophic niche, niche breadth, niche overlap, plant- pollinator network. Corresponding author Cândida M. L. Aguiar https://orcid.org/0000-0002-2220-5387 Departamento de Ciências Biológicas Universidade Estadual de Feira de Santana Av. Transnordestina s/nº, Novo Horizonte 44036-900, Feira de Santana-BA, Brasil. E-Mail: candida.aguiar@gmail.com Vizentin-Bugoni et al. (2018) pointed out that there is a notable gap in plant-pollinator network studies in Central Neotropical Savanna and that studies should be conducted in these areas of geographical gaps so that the spatial variation in plant-pollinator networks is better understood. The available database on the food plants exploited by bees is best known in the most southern part of the Brazilian savanna (= Cerrado) (19o to 24o S) (Pedro & Camargo, 1991; Carvalho & Bego, 1997; Andena et al., 2005; 2012; Biesmeijer & Slaa, 2006), however in the northern and middle portions of the Cerrado domain studies are scarce (Martins, 1995; Pacheco-Filho et al., 2015; Souza et al., 2018). In this study, we investigated bee-plant interactions, focusing on which plants are most important for maintaining bee populations in an area in the middle portion of the Brazilian Cerrado domain, which has undergone rapid agricultural expansion in the past two decades. This is an area of high 1 - PPG Ciências Agrárias, Universidade Federal do Recôncavo da Bahia (UFRB), Cruz das Almas, Bahia, Brazil 2 - Universidade Estadual de Feira de Santana (UEFS), Feira de Santana, Bahia, Brazil 3 - Universidade Federal da Paraíba (UFPB), João Pessoa, Paraíba, Brazil 4 - PPG Ecologia & Evolução, Universidade Estadual de Feira de Santana (UEFS), Feira de Santana, Bahia, Brazil RESEARCH ARTICLE - BEES Food Niche of Solitary and Social Bees (Hymenoptera: Apoidea) in a Neotropical Savanna Sociobiology 67(4): 554-565 (December, 2020) 555 interest for biodiversity conservation because it is located in the buffer zone of the Chapada Diamantina National Park (CDNP). The aim of this study was to investigate the resources utilization by bee populations, i.e, measuring their realized niches, which are delimited by interspecific interactions (Chesson, 2000; Biesmeijer & Slaa, 2006). We seek to use niche analysis tools to assess the interactions between bee species and between them and the associated flora. Our hypothesis is that bee species with similar requirements use a similar set of resources. For example, oil-collecting bees depend on a specific floral resource (Neff & Simpson, 2017), which is produced by a small subset of the melitophilous flora. Eusocial bees have similar requirements, as they continually depend on pollen and nectar sources to maintain their perennial colonies (Roubik, 1989). Our prediction is that regardless of the richness of flowering plant species, some plant species will be primarily exploited by bees, determining that bee species with similar requirements have higher rates of overlap with each other, than with species with different requirements. Material and Methods Study area In this region there is a mosaic of phytophysiognomies, such as campo rupestre (rupestrian fields, sandstone outcrop vegetation), cerrado (Brazilian savanna), caatinga (seasonally dry forest), sub-montane to montane semi-deciduous seasonal forests, sub-montane to montane evergreen riparian forests, wetlands and capitinga (Harley, 1995; Funch et al., 2009), sometimes separated by only a few kilometers. The climate is tropical humid, characterized by a marked seasonality. The rainiest period usually occurs from December to April while August to November is the driest period (Jesus et al., 1983). The mean annual rainfall in the area varies from 600 to 1000 mm, with a mean temperature of 22° C (CEI, 1994). Three sites, 900 to 1,500 m apart, located in the buffer zone of the Chapada Diamantina National Park (CDNP; 12° 20’ - 12° 25’ S; 41° 35’ - 41° 15’ W), municipality of Palmeiras, Bahia State, Brazil, were sampled. The local vegetation is a cerrado type with phytophysiognomy of herbaceous−shrubby field, with small, scattered trees. The species Byrsonima sericea DC and Byrsonima cydoniifolia A. Juss. (Malpighiaceae) were very abundant plant species in the three locations (Aguiar et al., 2017a). Sampling We collected bees that visited plants to gather floral resources in 2013 (October, November, and December), 2014 (January, February, March, September, and November) 2015 (February, March, April, August, October) and 2016 (January, March, May and July). In each of the 17 collection expeditions, bee-plant interactions were recorded over two consecutive days, from 8:00 to 16:00, over three transects (1,500 x 6m each). Each bee collected on a flower was considered a sampling unit. The bees were captured with entomological nets, without choice, for 5 to 10 minutes in each flowering plant, according to Sakagami et al. (1967). Fertile material from the plants visited by the bees was collected and herborized. Data analysis To evaluate the trophic niche breadth, we used the Shannon diversity index (H´) (Shannon, 1948). Additionally, we used the Pielou equitability index (J´) as an indicator of how plant diversity was used by each bee species (Ludwig & Reynolds, 1988). The level of niche overlap (NOih) between each pair of bee species was assessed using the Schoener index (1968), NOih = 1 - 1/2 Σk | pik - phk |, where: i and h are the bee species compared, pik and phk are the proportions of individuals, respectively of the bee species i and h collected in the plant species k. The pik value was obtained by dividing the number of individuals of species i collected in plant k by the total number of individuals of species i collected in all plants. The Schoener index is symmetrical and varies from 0 to 1. Only bee species represented by eight or more individuals were included in the analysis. The overlap between each bee species- pair (NOih) was analyzed in 105 possible combinations of pairs formed by 15 bee species. Following Aguiar (2003) and Aguiar et al. (2017b), the overlap of the trophic niche was considered low when the NOih value was less than or equal to 0.30, it was moderate when the value was greater than 0.30 and equal to or less than 0.70, and high if the NOih values were greater than 0.70. The data of the bee species (i) in each plant species (j) were used to build a Pij incidence matrix and calculate the connectance, which is the relationship between the actual number of interactions found and the theoretical number of possible interactions. To draw our network, we order the matrix in decrease frequencies of interactions between plants and bees and then we used the function plotweb from bipartite package (Dormann et al., 2009) in R program (R Core Team, 2020). Results The interactions between 75 bee species of bees and 62 plant species were recorded on this cerrado site (Fig 1, Table 1, Supplementary material 1). Byrsonima sericea, Serjania faveolata Radlk., Stigmaphyllon paralias A. Juss and Pityrocarpa moniliformis (Benth.) Luckow & R.W. Jobson were the plants with greatest number of links with bee species. Additionally, these plants received together almost half of the total visits (Table 1). The guild of oil-collecting bees, here composed of the species included in the Centridini, Tetrapediini and Tapinotaspidini tribes, showed high diversity and many interactions with B. sericea and S. paralias (Malpighiaceae) (Supplementary material 1). The bee-plant network showed connectance = 4.67%, with 242 interactions found out of 4,650 theoretically possible interactions. Considering only the guild of oil-collecting bees (26 species) and oil-plants (8 species), 75 interactions were recorded out of 208 theoretically possible and connectance was 16.8%. CO Santos, CML Aguiar, CF Martins, EB Santana, F França, E Melo, GMM Santos – Food niche of solitary and social bees556 Fig 1 Plant-bee network in a cerrado area. Plant species: P01 - Anemopaegma sp. 1, P02 - Banisteriopsis harleyi, P03 - Borreria verticillata , P04 - Bowdichia virgilioides, P05 - Byrsonima correifolia, P06 - Byrsonima cydoniifolia, P07 - Byrsonima dealbata, P08 - Byrsonima sericea, P09 - Centrosema coriaceum, P10 - Chamaecrista mucronata, P11 - Cordia rufescens, P12 - Croton sp. 1, P13 - Cuphea sessiliflora, P14 - Dalechampia brasiliensis, P15 - Diplopterys pubipetala, P16 - Eremanthus capitatus, P17 - Erythroxylum loefgrenii, P18 - Eugenia cf. punicifolia, P19 - Eugenia excelsa, P20 - Eugenia pistaciifolia, P21 - Evolvulus sp. 1, P22 - Fridericia cinerea, P23 - Gymneia sp.1, P24 - Herissantia crispa, P25 - Ipomoea incarnata, P26 - Ipomoea sp. 1, P27 - Jacquemontia sp. 1, P28 - Lasiolaena lychnophorioides, P29 - Lepidaploa chalybaea, P30 - Lippia sp. 1, P31 - Lippia sp. 2, P32 - Malpighiaceae sp. 1, P33 - Manihot sp. 1, P34 - Microstachys corniculata, P35 - Mikania elliptica, P36 - Mimosa somnians, P37 - Mimosa sp.1, P38 - Moquiniastrum blanchetianum, P39 - Myrtaceae sp. 1, P40 - Myrtaceae sp. 2, P41 - Passiflora edmundoi, P42 - Passiflora edulis, P43 - Periandra mediterranea, P44 - Piriqueta sidifolia, P45 - Pityrocarpa moniliformis, P46 - Rhaphiodon echinus, P47 - Senegalia langsdorffii, P48 - Senna acuruensis, P49 - Senna macranthera, P50 - Senna macranthera, P51 - Serjania faveolata, P52 - Serjania lethalis, P53 - Serjania sp. 1, P54 - Serjania sp. 2, P55 - Serjania sp. 3, P56 - Simarouba amara, P57 - Stachytarpheta crassifolia, P58 - Stigmaphyllon paralias, P59 - Stylosanthes scabra, P60 - Turnera sp. 1, P61 - Urochloa decumbens, P62 - Waltheria cf. indica. Bee species: B01 - Acanthopus excellens, B02 - Apis melífera, B03 - Augochlora (Augochlora) sp. 5, B04 - Augochlora (Oxystoglossella) sp. 2, B05 - Augochlora (Oxystoglossella) sp. 3, B06 - Augochloropsis sp. 3, B07 - Augochloropsis sp. 4, B08 - Augochloropsis sp. 5, B09 - Augochloropsis sp. 6, B10 - Augochloropsis sp. 7, B11 - Augochloropsis sp. 8, B12 - Bombus morio, B13 - Centris varia, B14 - Centris moerens, B15 - Centris tetrazona, B16 - Centris lutea, B17 - Centris aenea, B18 - Centris caxienses, B19 - Centris cf. spilopoda, B20 - Centris decolorata, B21 - Centris nitens, B22 - Centris perforator, B23 - Centris sp. 1, B24 - Centris sp. 3, B25 - Centris sp. 6, B26 - Centris tarsata, B27 - Ceratina (Crewella) sp.1, B28 - Ceratina (Crewella) sp.2, B29 - Ceratina (Crewella) sp.3, B30 - Colletes sp.1, B31 - Diadasia sp.1, B32 - Dialictus opacus, B33 - Dicranthidium sp. 1, B34 - Epicharis analis, B35 - Epicharis bicolor, B36 - Epicharis cockerelli, B37 - Epicharis flava, B38 - Euglossa cordata, B39 - Eulaema nigrita, B40 - Exomalopsis (Exomalopsis) sp. 2, B41 - Exomalopsis (Phanomalopsis) sp. 1, B42 - Florilegus sp. 1, B43 - Frieseomelitta francoi, B44 - Geotrigona mombuca, B45 - Leiopodus abnormis, B46 - Lophopedia nigrispinis, B47 - Megachile (Pseudocentron) sp. 3, B48 - Megachile sp. 8, B49 - Melipona quadrifasciata, B50 - Melitoma sp. 1, B51 - Melitomella grisescens, B52 - Mesoplia friesei, B53 - Mesoplia rufipes, B54 - Monoeca affs. moure, B55 - Nannotrigona testaceicornis, B56 - Oxaea flavescens, B57 - Paratrigona incerta, B58 - Partamona combinata, B59 - Pseudaugochlora pandora, B60 - Pseudaugochlora sp. 1, B61 - Scaptotrigona aff. postica, B62 - Tapinotaspoides sp.1, B63 - Temnosoma cf. metallicum, B64 - Tetragonisca sp. 1, B65 - Tetrapedia amplitarsis, B66 - Tetrapedia diversipes, B67 - Trigona hyalinata, B68 - Trigona spinipes, B69 - Tropidopedia nigrocarinata, B70 - Urbanapsis diamantina, B71 - Xanthopedia sp., B72 - Xylocopa subcyanea, B73 - Xylocopa cearensis, B74 - Xylocopa sp. 2, B75 - Xylocopa frontalis. Sociobiology 67(4): 554-565 (December, 2020) 557 Fifteen bee species were included in the niche analyzes. The eusocial species Trigona spinipes (Fabricius) and Apis mellifera L. exploited the largest plant spectrum (Fig 1; Supplementary material 1) and showed high equitability in the distribution of visits to the plants, with broader trophic niches (H’>2.00) (Table 2). Epicharis bicolor Smith, Centris aenea Lepeletier and Melitoma sp.1 presented the narrowest trophic niches, and the first two showed a foraging concentration in B. sericea, causing low equitability of visits to the spectrum of exploited plants, which decreased the value of the H’ index downwards (Table 2; Supplementary material 1). Family Plant species Code N1 N2 Asteraceae Eremanthus capitatus (Spreng.) MacLeish P16 2 3 Asteraceae Lasiolaena lychnophorioides Roque et al. P28 1 1 Asteraceae Lepidaploa chalybaea (Mart. ex DC.) H.Rob. P29 3 3 Asteraceae Mikania elliptica DC. P35 2 3 Asteraceae Moquiniastrum blanchetianum (DC.) G. Sancho P38 5 11 Bignoniaceae Anemopaegma sp. 1 P01 2 2 Bignoniaceae Fridericia cinerea (Bureau ex K.Schum.) L.G.Lohmann P22 1 2 Boraginaceae Cordia rufescens A.DC. P11 1 1 Convolvulaceae Evolvulus sp. 1 P21 1 1 Convolvulaceae Ipomoea incarnata (Vahl) Choisy P25 2 2 Convolvulaceae Ipomoea sp. 1 P26 2 4 Convolvulaceae Jacquemontia sp1. Choisy P27 3 3 Erythroxylaceae Erythroxylum loefgrenii Diogo P17 2 2 Euphorbiaceae Croton sp. 1 P12 1 1 Euphorbiaceae Dalechampia brasiliensis Lam. P14 1 1 Euphorbiaceae Manihot sp. 1 P33 2 20 Euphorbiaceae Microstachys corniculata (Vahl) Griseb. P34 1 3 Fabaceae Bowdichia virgilioides Kunth P04 4 5 Fabaceae Centrosema coriaceum Benth. P09 5 7 Fabaceae Chamaecrista mucronata (Spreng.) H.S.Irwin & Barneby P10 2 5 Fabaceae Mimosa somnians Humb. & Bonpl. ex Willd. P36 1 2 Fabaceae Mimosa sp.1 P37 1 1 Fabaceae Periandra mediterranea (Vell.) Taub. P43 5 12 Fabaceae Pityrocarpa moniliformis (Benth.) Luckow & R.W.Jobson P45 12 36 Fabaceae Senegalia langsdorffii (Benth.) Seigler & Ebinger P47 6 15 Fabaceae Senna acuruensis (Benth.) H.S.Irwin & Barneby P48 1 1 Fabaceae Senna macranthera (DC. ex Collad.) H.S.Irwin & Barneby P49 2 9 Fabaceae Senna macranthera var. micans (Nees) H.S.Irwin & Barneby P50 2 3 Fabaceae Stylosanthes scabra Vogel P59 3 3 Lamiaceae Gymneia sp. 1 P23 1 1 Lamiaceae Rhaphiodon echinus Schauer P46 1 1 Lythraceae Cuphea sessiliflora A.St.-Hil. P13 1 1 Malpighiaceae Banisteriopsis harleyi B.Gates P02 2 4 Table 1. Plant species exploited by bee species in a cerrado area in the Chapada Diamantina, Bahia, Brazil. N1: Number of bee species visiting each plant species. N2: Number of individual bees collected from each plant species. CO Santos, CML Aguiar, CF Martins, EB Santana, F França, E Melo, GMM Santos – Food niche of solitary and social bees558 Family Plant species Code N1 N2 Malpighiaceae Byrsonima correifolia A.Juss. P05 2 4 Malpighiaceae Byrsonima cydoniifolia A.Juss. P06 6 9 Malpighiaceae Byrsonima dealbata Griseb. P07 4 7 Malpighiaceae Byrsonima sericea DC. P08 20 232 Malpighiaceae Diplopterys pubipetala (A.Juss.) W.R.Anderson & C.C.Davis P15 2 2 Malphigiaceae Malpighiaceae sp. 1 P32 1 1 Malpighiaceae Stigmaphyllon paralias A.Juss. P58 13 58 Malvaceae Herissantia crispa (L.) Brizicky P24 2 21 Malvaceae Waltheria cf. indica L. P62 2 2 Myrtaceae Eugenia cf. punicifolia (Kunth) DC. P18 2 7 Myrtaceae Eugenia excelsa O.Berg P19 1 1 Myrtaceae Eugenia pistaciifolia DC. P20 1 1 Myrtaceae Myrtaceae sp. 1 P39 4 5 Myrtaceae Myrtaceae sp. 2 P40 1 3 Passifloraceae Passiflora edmundoi Sacco P41 1 1 Passifloraceae Passiflora edulis Sims P42 6 7 Poaceae Urochloa decumbens (Stapf) R.D.Webster P61 1 1 Rubiaceae Borreria verticillata (L.) G.Mey P03 1 1 Sapindaceae Serjania faveolata Radlk. P51 18 78 Sapindaceae Serjania lethalis A.St.-Hil. P52 6 39 Sapindaceae Serjania sp. 1 P53 1 3 Sapindaceae Serjania sp. 2 P54 3 14 Sapindaceae Serjania sp. 3 P55 9 41 Simaroubaceae Simarouba amara Aubl. P56 6 14 Turneraceae Piriqueta sidifolia (Cambess.) Urb. P44 5 9 Turneraceae Turnera sp. 1 P60 1 2 Verbenaceae Lippia sp. 1 P30 3 25 Verbenaceae Lippia sp. 2 P31 5 21 Verbenaceae Stachytarpheta crassifolia Schrad. P57 1 1 Table 1. Plant species exploited by bee species in a cerrado area in the Chapada Diamantina, Bahia, Brazil. N1: Number of bee species visiting each plant species. N2: Number of individual bees collected from each plant species. (Continuation) The trophic niche overlap between each bee species pair ranged from 0.01 to 0.87, being higher between E. bicolor and C. aenea, and between Trigona hyalinata (Lepeletier) and E. bicolor (Table 2). The vast majority of species pairs analyzed (~75%) showed low overlap of the trophic niche (NO<0.33), and approximately half of them had a very low level of overlap (NO<0.1). Only four pairs showed high overlap (NO>0.7): E. bicolor/C. aenea; T. hyalinata/E. bicolor; Urbanapsis diamantina Aguiar and Melo/T. hyalinata; T. hyalinata/C. aenea. The high level of overlap found in these pairs was mainly influenced by the exploitation of resources from B. sericea (P08), floral oil and/or pollen (Supplementary material 1). A. mellifera showed a low overlap of the trophic niche with the other bee species (Table 2), due mainly to scattered foraging in 23 plant species. However, this exotic species heavily exploited S. faveolata, a food plant visited by many native bee species (Supplementary material 1). Discussion Bees exploited a diverse flora, however a small set of plant species, either due to their abundance or by providing specific resources, can be considered as key species for the maintenance of bee populations in this community. Sociobiology 67(4): 554-565 (December, 2020) 559 B02 B14 B17 B18 B19 B22 B27 B34 B35 B50 B61 B67 B68 B69 B70 B14 0.11 B17 0.11 0.26 B18 0.14 0.25 0.43 B19 0.05 0.25 0.50 0.39 B22 0.18 0.24 0.28 0.18 0.18 B27 0.02 0.00 0.08 0.06 0.00 0.20 B34 0.06 0.25 0.44 0.37 0.44 0.29 0.10 B35 0.07 0.25 0.87 0.45 0.50 0.21 0.03 0.40 B50 0.01 0.00 0.00 0.11 0.00 0.00 0.00 0.00 0.06 B61 0.14 0.00 0.02 0.10 0.00 0.01 0.03 0.01 0.07 0.10 B67 0.06 0.25 0.72 0.50 0.50 0.18 0.00 0.37 0.78 0.19 0.20 B68 0.21 0.09 0.07 0.21 0.05 0.12 0.01 0.05 0.11 0.28 0.21 0.24 B69 0.30 0.22 0.22 0.33 0.22 0.29 0.00 0.22 0.28 0.11 0.13 0.33 0.32 B70 0.16 0.25 0.56 0.50 0.50 0.29 0.00 0.37 0.61 0.33 0.10 0.74 0.40 0.44 H’ 2.45 1.91 0.69 1.72 0.97 1.99 1.75 0.89 0.35 0.66 1.89 0.77 2.59 1.15 0.94 J’ 0.78 0.98 0.31 0.88 0.89 0.96 0.90 0.81 0.32 0.95 0.79 0.70 0.85 0.83 0.85 Spl 23 7 9 7 3 8 7 3 3 2 11 3 21 4 3 Nab 168 8 121 18 8 17 10 27 34 8 96 32 78 9 9 Table 2. Trophic niche overlap among bee species in a cerrado area in Chapada Diamantina, Bahia, Brazil. H’: Niche breadth. J’: Equitabil- ity index. Spl: Number of plant species visited by each bee species. Nab: number of individuals of each bee species. B02 - Apis mellifera, B14 - Centris moerens, B17 - Centris aenea, B18 - Centris caxiensis, B19 - Centris cf. spilopoda, B22 - Centris perforator, B27 -Ceratina (Crewella) sp.1, B34 - Epicharis analis, B35 - Epicharis bicolor, B50 - Melitoma sp.1, B61 - Scaptotrigona aff. postica, B67 - Trigona hyalinata, B68 - Trigona spinipes, B69 - Tropidopedia nigrocarinata, B70 - Urbanapsis diamantina B. sericea and S. paralias are plants that produce floral oil. In addition, B. sericea pollen is collected by several distinct bee groups (Teixeira & Machado, 2000), which increases its attractiveness for both oil-bees and non-oil-bees. Another aspect that increases the possibilities of B. sericea interactions with bees is the great local abundance of this plant species (Aguiar et al., 2017a). The Serjania genus comprises nectar-producing species (Matos & Santos, 2017), and P. moniliformis is a nectar (Santos et al., 2018) and pollen source for bees (Maia- Silva et al., 2012). The visits of oil-bees to oil-plant flowers are not optional as these bees demand floral oil to complete their reproductive cycle (Alves-dos-Santos et al., 2007; Neff & Simpson, 2017). Oil-bees have, at least in part, the same requirements, all of which demand floral oil, which explains the high overlap of trophic niche. It is expected that species with similar ecological requirements will show some redundancy in the use of resources and high overlap in their niches. In fact, the connectance in the oil-bees guild and oil-plants is approximately four times greater than the connectance found in the entire community. In the small world formed by the oil- bees and oil-plants, species share evolutionary histories and mutually specialized structures (Bezerra et al., 2009), forming modules in which interactions have higher intimacy than in the network as a whole. Hembry et al. (2018) demonstrated that the level of interaction intimacy affects the structure of communities. The most abundant oil-bee species in this assemblage was C. aenea, who exploited floral resources of a diversity of non-phylogenetically related plant species, that is, a tendency to a generalist foraging behavior, previously pointed out in other habitats (Aguiar & Gaglianone, 2003; Mello et al., 2013). However, its niche breadth, measured by the H’ index, showed one of the lowest values among these bee species, because of the high concentration of nesting females on the oil-plant B. sericea. The strong mutualistic interaction between C. aenea and B. sericea has been reported in many habitats (Mello et al., 2013), as well as the behavior of this oil-bee to nest in aggregations near this food plant (Aguiar & Gaglianone, 2003). B. sericea played a central role in the trophic niche of C. aenea and other oil-bees, since the exploitation of the floral resources of this plant explains all the cases in which there was a high overlap of trophic niche (NO>0.70), even when one of the species involved was not an oil-bee, such as T. hyalinata (Meliponini), whose visits to B. sericea were probably for pollen foraging. Among the eusocial species, T. spinipes showed the broader trophic niche, as expected based on its supergeneralist foraging behavior (Biesmeijer & Slaa, 2006; Giannini et al., 2015; Pacheco-Filho et al., 2015). Its trophic niche breadth in this habitat was influenced both by the richness of plant species visited and by the distribution of the foragers in many floral resources. This scattered foraging in several plant CO Santos, CML Aguiar, CF Martins, EB Santana, F França, E Melo, GMM Santos – Food niche of solitary and social bees560 species contributed to the low level of niche overlap of this species with the other bee species, including A. mellifera and the congeneric species T. hyalinata. Biesmeijer and Slaa (2006) highlighted that these two congeneric species, despite having aggressive group forager behavior (Nieh et al., 2003, 2005; Slaa et al., 2003), in general present different diets and probably do not interact regularly during foraging. Surprisingly, T. spinipes and A. mellifera, species that have a strong association with each other in the use of floral resources (e.g. Biesmeijer & Slaa, 2006) and are supergeneralists species in bee-plant networks (Giannini et al., 2015), also showed low overlap level in our study, which was influenced by the allocation of many honeybee foragers in three plant species that received few visits of T. spinipes. These two supergeneralist species have been considered fundamental to the maintenance of the bee-plant networks, although they have different effects on network structure, with A. mellifera having a strong effect on nestedness, whereas T. spinipes has a main effect on the niche overlap of the bees (Giannini et al., 2015). The low overlap of the trophic niche of A. mellifera with the other bee species was also caused by scattering of foragers in many plant species. However, some of these plant species, such as S. faveolata, were important in the diet of other bees. The distribution of the samples over a long period (almost 4 years), as well as the large sampling effort, favored a more robust characterization of the food niche of the bee populations, as it allows recording of bee-plant interactions in different periods of flowering of the melitophilous plants, as well as the registration of different generations of bee species. On the other hand, it probably contributed to the very low values of niche overlap found, which may be related to the differences between flowering periods of the melitophilous plants and between periods of nesting activity of different species of solitary bees. Additionally, the low levels of niche overlap found may be, at least in part, influenced by the sampling method, collection of bees during foraging, as previously discussed by Ranta and Lundberg (1981). These authors compared the overlapping levels of the food niche between Bombus species using three sampling methods, and found that the mean niche overlap values were significantly lower when calculated using direct observations of flower visits data than when using analyses of pollen contents in pollen loads and in nectar loads. According to the authors, these differences in overlapping levels would be largely explained by differences in the contribution of different food plants in number of pollen grains for the pollen loads, since only a few plant species were dominant, as they are represented by many pollen grains in the pollen loads, resulting in an increase in the niche overlap values. Finally, we emphasize that the method of collecting bees on flowers is more viable for the analysis of the food niche in tropical bee assemblages, even although only a few species can be evaluated according to their abundance. Acknowledgments We are grateful to the bee specialists who identified some bee species collected in this research (Felipe Vivallo, Antonio Aguiar, Fernando Zanella, Cristina Gaglianone and Willian Aguiar), and to Emanuelle Brito for assistance with the figures. We also thank the National Council for Scientific and Technological Development, Brazil (CNPq, no. 558228/2009-7, PELD; 403774/2012-8, PELD; 474065/2013-8) for financial support for this project. CNPq granted research fellowship to C.F. Martins and G.M.M. Santos. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior - Brasil (CAPES) - Finance Code 001. CAPES granted CO Santos and EB Santana. References Aguiar, C.M.L. (2003). Utilização de recursos florais por abelhas (Hymenoptera: Apoidea) em uma área de Caatinga (Itatim, Bahia, Brasil). Revista Brasileira de Zoologia, 20: 457-467. doi: 10.1590/S0101-81752003000300015 Aguiar, C.M.L. & Gaglianone, M.C. (2003). Nesting biology of Centris (Centris) aenea Lepeletier (Hymenoptera, Apidae, Centridini). Revista Brasileira de Zoologia, 20: 601-606. Aguiar, C.M.L., Lua, S., Silva, M., Peixoto, P.E.C., Alvarez, H.M. & Santos, G.M.M. (2017a). The similar usage of a common key resource does not determine similar responses by species in a community of oil-collecting bees. Sociobiology, 64: 69-77. doi: 10.13102/sociobiology.v64i1.1210 Aguiar, C.M.L., Caramés, J., França, F. & Melo, E. (2017b). Exploitation of floral resources and niche overlap within an oil-collecting bee guild (Hymenoptera, Apidae) in a neotropical savannah. Sociobiology, 64: 78-84. doi: 10.13102/ sociobiology.v64i1.1250 Alves-dos-Santos, I., Machado, I.C. & Gaglianone, M.C. (2007). História natural das abelhas coletoras de óleo. Oecologia Brasiliensis, 11: 544-557 Andena, S.R., Bego, L.R. & Mechi, M.R. (2005). A comunidade de abelhas (Hymenoptera, Apoidea) de uma área de Cerrado (Corumbataí, SP) e suas visitas às flores. Revista Brasileira de Zoociências, 7: 55-91 Andena, S.R., Santos, E.F. & Noll, F.B. (2012). Taxonomic diversity, niche width and similarity in the use of plant resources by bees (Hymenoptera: Anthophila) in a cerrado area. Journal of Natural History, 46: 27-28. doi: 10.1080/00222933.2012.681317 Bezerra, E.L.S., Machado, I.C. & Mello, M.A.R. (2009). Pollination networks of oil-flowers: a tiny world within the smallest of all worlds. Journal of Animal Ecology, 78: 1096- 1101. doi: 10.1111/j.1365-2656.2009.01567.x Sociobiology 67(4): 554-565 (December, 2020) 561 Biesmeijer, J.C. & Slaa, J. (2006). The structure of eusocial bee assemblages in Brazil. Apidologie, 37: 240-258. doi: 10.1051/apido:2006014 Carvalho, A.M.C. & Bego, L.R. (1997). Explotation of available resources by bee fauna (Apoidea- Hymenoptera) in the Reserva Ecológica do Panga, Uberlândia, State of Minas Gerais, Brazil. Revista Brasileira de Entomologia, 41: 101-107. Centro de Estatística e Informações [CEI]. (1994). Informações básicas dos municípios baianos: Região Chapada Diamantina. Salvador: Secretaria de Planejamento. Chesson, P. (2000). Mecanisms of maintenance of species diversity. Annual Review of Ecology and Sistematics, 31: 343-366. doi:10.1146/annurev.ecolsys.31.1.343 Dormann, C.F., Fruend, J., Bluethgen, N. & Gruber B. (2009). Indices, graphs and null models: analyzing bipartite ecological networks. The Open Ecology Journal, 2: 7-24.doi: 10.2174/18 74213000902010007 Freitas, B.M., Imperatriz-Fonseca, V.L., Medina, L.M., Kleinert, A.M.P., Galetto, L., Nates-Parra, G. & Quezada-Euán, J.J.G. (2009). Diversity, threats and conservation of native bees in the Neotropics. Apidologie, 40: 332-346.doi: 10.1051/apido/2009012 Funch, R., Harley, R. & Funch, L. (2009). Mapping and evaluation of the state of conservation of the vegetation in and surrounding the Chapada Diamantina National Park, NE, Brazil. Biota Neotropica, 9: 21-30. doi: 10.1590/S1676- 06032009000200001 Giannini, T.C., Garibaldi, L.A., Costa, A.L.A, Silva, J.S., Maia, K.P., Saraiva, A.M., Guimarães Jr., P.R., Kleinert, A.M.P. (2015). Native and non-native supergeneralist bee species have different effects on plant-bee networks. PLoS ONE, 10: e0137198. doi: 10.1371/journal.pone.0137198 Harley, R.M. (1995). Introduction. In B.L. Stannard (Ed.). Flora of the Pico das Almas, Chapada Diamantina, Brazil (pp.1-42) Kew: Royal Botanic Gardens. Hembry, D.H., Raimundo, R.L.G., Newman, E.A., Atkinson, L., Guo, C., Guimarães Jr., P.R. & Gillespie, R.G. (2018). Does biological intimacy shape ecological network structure? A test using a brood pollination mutualism on continental and oceanic islands. Journal of Animal Ecology, 87: 1160-1171. doi: 10.1111/1365-2656.12841 Jesus, E.F., Falk, F.H. & Marques, T.M. (1983). Caracterização geográfica e aspectos geológicos da Chapada Diamantina, Bahia. Centro editorial e didático da Universidade Federal da Bahia, Salvador, p. 50. Kevan P.K. (2018). Conserving pollinators for agriculture, forestry and nature. In, D.W. Roubik (Ed), The Pollination of Cultivated Plants, (pp. 29-33). Rome: FAO Ludwig, J.A. & Reynolds, J.F. (1988). Statistical ecology: A primer on methods and computing. New York: John Wiley & Sons, 339 p. Maia-Silva, C., Silva, C.I., Hrncir, M., Queiroz, R.T. & Imperatriz-Fonseca, V.L. (2012). Guia de Plantas visitadas por abelhas na Caatinga. 1a ed. Fortaleza: Editora Fundação Brasil Cidadão. 191p. Maia-Silva, C., Limão, A.A.C., Silva, C.I., Imperatriz-Fonseca, V.L. & M. Hrncir (2020). Stingless bees (Melipona subnitida) overcome severe drought events in the Brazilian tropical dry forest by opting for high-profit food sources. Neotropical Entomology, 49: 595-603. doi:10.1007/s13744-019-00756-8 Martins, C.F. (1995). Flora apícola e nichos tróficos de abelhas (Hym, Apoidea) na Chapada Diamantina (Lençóis-BA, Brasil). Revista Nordestina de Biologia, 10: 119-140 Matos, V.R., Santos, F.A.R. (2017). Identificação botânica da própolis - análise palinológica. In, J.M.C. Nunes, M.R.B. Matos (Orgs), Litoral Norte da Bahia: caracterização ambiental, biodiversidade e conservação (pp. 181-194). Salvador: EDUFBA. Mello, M.A.R., Bezerra, E.L.S. & Machado, I.C. (2013). Functional roles of Centridini oil bees and Malpighiaceae oil flowers in biome-wide pollination networks. Biotropica, 45: 45-53. doi: 10.2307/23360240 Neff, J.L. & Simpson, B.B. (2017). Vogel’s great legacy: The oil flower and oil-collecting bee syndrome. Flora, 232: 104- 116. doi:10.1016/j.flora.2017.01.003 Nieh, J.C., Contrera F.A.L. & Nogueira-Neto P. (2003). Pulsed mass recruitment by a stingless bee, Trigona hyalinata. Proceedings of the Royal Society B, 270: 2191-2196. doi doi:10.1098/rspb.2003.2486 Nieh, J.C, Kruizinga, K., Barreto, L.S., Contrera, F.A.L. & Imperatriz-Fonseca, V.L. (2005). Effect of group size on the aggression strategy of an extirpating stingless bee, Trigona spinipes. Insectes Sociaux, 52: 147-154 Pacheco-Filho, A., Verola, C.F., Lima-Verde, L.W. & Freitas, B.M. (2015). Bee-flower association in the Neotropics: implications to bee conservation and plant pollination. Apidologie, 46: 530-541. doi: 10.1007/s13592-014-0344-8 Pedro, S.R.M. & Camargo, J.M.F. (1991). Interactions on floral resource between the Africanized honey bee (Apis mellifera L.) and native bee community (Hymenoptera: Apoidea) in a natural “cerrado” ecosystem in southeast Brazil. Apidologie, 22: 397-415. R Core Team (2020). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL: https://www.R-project.org/ Ranta, E. & Lundberg, H. (1981). Food niche of bumblebees: a comparison of three data collecting methods. Oikos, 36: 12-16 Roubik, D.W. (1989). Ecology and Natural History of Tropical Bees. Cambridge: Cambridge University Press, 514p. Sakagami, S.F., Laroca, S. & Moure, J.S. (1967). Wild bees biocenotics in São José dos Pinhais (PR), South Brazil CO Santos, CML Aguiar, CF Martins, EB Santana, F França, E Melo, GMM Santos – Food niche of solitary and social bees562 preliminary report. Journal of the Faculty of Science Hokkaido University, 16: 253-291 Santos, F.A.R., Kiill, L.H.P., Carneiro-Torres, D.S., Lima e Lima, L.C., Silva, T,M.S., Novais, J.S., Dórea, M.C., Carneiro, C.E. & Correia, M.C.N. (2018). Espécies melíferas. In, L. Coradin, J. Camillo & F.G.C. Pareyn (Eds.), Espécies nativas da flora brasileira de valor econômico atual ou potencial: plantas para o futuro: região Nordeste, (pp. 971- 1010). Brasília: MMA. (Série Biodiversidade; 51) , Accessed date 08/ 06/ 2020 Schoener, T.W. (1968). The Anolis lizard of Bimini: Resource partitioning in a complex fauna. Ecology, 49: 704-726. doi: 10.2307/1935534 Shannon, C.E. (1948). The mathematical theory of communication. In, C.E. Shannon & W. Weaver (Eds), The mathematical theory of communication, (pp. 3-91), Urbana: University of Illinois Press. Slaa, E.J., Wassenberg, J. & Biesmeijer, J.C. (2003). The use of field-based social information in eusocial foragers: local enhancement among nestmates and heterospecifics in stingless bees. Ecological Entomology, 28: 369-379 Souza, C.S., Maruyama, P.K., Aoki, C., Sigrist, M.R., Raizer, J., Gross, C.L., Araujo, A.C. (2018). Temporal variation in plant-pollinator networks from seasonal tropical environments: higher specialization when resources are scarce. Journal of Ecology, 106: 2409-2420. doi: 10.1111/1365-2745.12978 Teixeira, L.A.G. & Machado, I.C. (2000). Sistemas de polinização e reprodução de Byrsonima sericea DC (Malpighiaceae). Acta Botanica Brasilica, 14: 347-357. doi: 10.1590/S0102- 33062000000300011 Vizentin-Bugoni, J., Maruyama, P. K., Souza, C. S., Ollerton, J., Rech, A. R. & Sazima, M. (2018). Plant-pollinator networks in the tropics: A review. In, W. Dáttilo & V. Rico-Gray (Eds.), Ecological networks in the tropics, (pp. 73-91). Dordrecht, the Netherlands: Springer. doi:10.1007/978-3-319-68228-0_6 Sociobiology 67(4): 554-565 (December, 2020) 563 Bee species Bee Code Nab Plant species ANDRENIDAE Oxaeini Oxaea flavescens Klug, 1807 B56 2 P1(1), P49(1) APIDAE Apini Apis mellifera Linnaeus, 1758 B02 168 P6(1), P8(8), P17(1), P18(6), P24(20), P28(1), P30(23), P31(11), P32(1), P35(2), P36(2), P39(2), P45(2), P47(10), P51(42), P52(1), P53(3), P54(10), P55(18), P56(1), P58(1), P59(1), P62(1) Bombini Bombus morio (Swederus, 1787) B12 4 P9(1), P10(1), P22(2) Centridini Centris aenea Lepeletier, 1841 B17 121 P4(1), P6(1), P8(102), P15(1), P18(1), P31(4), P42(1), P45(9), P56(1) Centris caxienses Ducke, 1907 B18 18 P5(3), P6(2), P8(7), P20(1), P31(2), P39(1), P58(2) Centris decolorata Lepeletier, 1841 B20 2 P8(1), P42(1) Centris nitens Lepeletier, 1841 B21 1 P8(1) Centris varia (Erichson, 1849) B13 1 P8(1) Centris tarsata Smith, 1874 B26 3 P8(1), P13(1), P31(1) Centris moerens (Perty, 1833) B14 8 P1(1), P8(2), P42(1), P47(1), P48(1), P50(1), P57(1) Centris lutea Friese, 1899 B16 1 P2(1) Centris perforator (Smith, 1874) B22 17 P4(2), P8(3), P9(2), P10(4), P15(1), P42(1), P45(2), P51(2) Centris cf. spilopoda Moure, 1969 B19 8 P7(3), P8(4), P19(1) Centris tetrazona Moure & Seabra, 1962 B15 5 P8(1), P42(2), P45(1), P56(1) Centris sp. 1 B23 4 P6(1), P8(3) Centris sp. 3 B24 1 P8(1) Centris sp. 6 B25 1 P45(1) Epicharis analis Lepeletier, 1841 B34 27 P7(2), P8(10), P45(15) Epicharis bicolor Smith, 1854 B35 34 P8(31), P45(1), P58(2) Epicharis cockerelli Friese, 1900 B36 4 P8(4) Epicharis flava Friese, 1900 B37 1 P8(1) Emphorini Diadasia sp. 1 B31 1 P23(1) Melitoma sp. 1 B50 8 P26(3), P58(5) Melitomella grisescens (Ducke, 1907) B51 2 P16(2) Ericrocidini Acanthopus excellens Schrottky, 1902 B01 1 P55 (1) Mesoplia friesei (Ducke, 1902) B52 2 P14(1), P46(1) Mesoplia rufipes (Perty, 1833) B53 4 P4(1), P31(3) Eucerini Florilegus sp. 1 B42 1 P29(1) Euglossini Euglossa cordata (Linnaeus, 1758) B38 2 P8(1), P35(1) Eulaema nigrita Lepeletier, 1841 B39 5 P9(1), P30(1), P42(1), P51(2) Exomalopsini Exomalopsis (Phanomalopsis) sp. 1 B41 1 P55(1) Exomalopsis (Exomalopsis) sp. 2 B40 1 P55(1) Supplementary Material 1. Species of bees and plants visited in a cerrado area in the Chapada Diamantina, Bahia, Brazil. Nab: number of individuals of each bee species. Within the brackets the number of individuals of each bee species collected in each plant species is presented. The plant species codes according to Table 1. CO Santos, CML Aguiar, CF Martins, EB Santana, F França, E Melo, GMM Santos – Food niche of solitary and social bees564 Bee species Bee Code Nab Plant species Meliponini Frieseomelitta francoi (Moure, 1946) B43 1 P44(1) Geotrigona mombuca (Smith, 1863) B44 2 P45(1), P55(1) Melipona quadrifasciata Lepeletier, 1836 B49 2 P45(1), P47(1) Nannotrigona testaceicornis (Lepeletier, 1836) B55 4 P38(1), P44(1), P52(1), P55(1) Paratrigona incerta Camargo & Moure, 1994 B57 7 P7(1), P8(4), P38(1), P55(1) Partamona combinata Pedro & Camargo, 2003 B58 2 P47(1), P55(1) Scaptotrigona aff. postica (Latreille, 1807) B61 96 P16(1), P17(1), P33(17), P38(7), P43(2), P44(2), P45(1), P52(32), P55(16), P56(7), P58(10) Tetragonisca sp. 1 B64 1 P43(1) Trigona hyalinata (Lepeletier, 1836) B67 32 P8(23), P52(3), P58(6) Trigona spinipes (Fabricius, 1793) B68 78 P2(3), P6(3), P8(4), P25(1), P27(1), P30(1), P33(3), P34(3), P38(1), P39(1), P40(3), P41(1), P43(7), P47(1), P49(8), P50(2), P51(5), P54(3), P56(3), P58(22), P60(2) Protepeolini Leiopodus abnormis (Jörgensen, 1912) B45 1 P27(1) Tapinotaspidini Lophopedia nigrispinis (Vachal, 1909) B46 2 P45(1), P51(1) Monoeca affs.moure Aguiar, 2012 B54 1 P58(1) Tapinotaspoides sp. 1 B62 1 P5(1) Tropidopedia nigrocarinata Aguiar & Melo, 2007 B69 9 P8(2), P43(1), P51(5), P58(1) Urbanapsis diamantina Aguiar & Melo, 2007 B70 9 P8(5), P51(1), P58(3) Xanthopedia sp. B71 5 P8(4), P51(1) Tetrapediini Tetrapedia amplitarsis Friese, 1899 B65 3 P8(3) Tetrapedia diversipes Klug, 1810 B66 4 P43(1), P51(2), P61(1) Xylocopini Ceratina (Crewella) sp.1 B27 10 P4(1), P11(1), P12(1), P37(1), P39(1), P44(4), P45(1) Ceratina (Crewella) sp.2 B28 1 P29(1) Ceratina (Crewella) sp.3 B29 1 P26(1) Xylocopa cearensis Ducke, 1910 B73 4 P9(2), P51(2) Xylocopa frontalis (Olivier, 1789) B75 1 P54(1) Xylocopa subcyanea Pérez, 1901 B72 1 P51(1) Xylocopa sp. 2 B74 1 P9(1) COLLETIDAE Colletes sp.1 B30 5 P51(5) HALICTIDAE Augochlorini Augochlora (Oxystoglossella) sp. 2 B04 1 P56(1) Augochlora (Oxystoglossella) sp. 3 B05 5 P25(1), P51(2), P58(1), P59(1) Augochlora (Augochlora) sp. 5 B03 1 P52(1) Augochloropsis sp. 3 B06 1 P47(1) Augochloropsis sp. 4 B07 1 P38(1) Augochloropsis sp. 5 B08 7 P8(3), P21(1), P24(1), P27(1), P59(1) Augochloropsis sp. 6 B09 1 P7(1) Augochloropsis sp. 7 B10 6 P6(1), P8(1), P51(3), P58(1) Augochloropsis sp. 8 B11 2 P51(1), P52(1) Pseudaugochlora pandora (Smith, 1853) B59 1 P51(1) Pseudaugochlora sp. 1 B60 1 P44(1) Sociobiology 67(4): 554-565 (December, 2020) 565 Plant Species Code Anemopaegma sp. 1 Mart. ex Meisn. P01 Banisteriopsis harleyi B. Gates P02 Borreria verticillata (L.) G. Mey P03 Bowdichia virgilioides Kunth P04 Byrsonima correifolia A.Juss. P05 Byrsonima cydoniifolia A.Juss. P06 Byrsonima dealbata Griseb. P07 Byrsonima sericea DC. P08 Centrosema coriaceum Benth. P09 Chamaecrista mucronata (Spreng.) H.S.Irwin & Barneby P10 Cordia rufescens A.DC. P11 Croton sp.1 P12 Cuphea sessiliflora A.St.-Hil. P13 Dalechampia brasiliensis Lam. P14 Diplopterys pubipetala (A.Juss.) W.R.Anderson & C.C.Davis P15 Eremanthus capitatus (Spreng.) MacLeish P16 Erythroxylum loefgrenii Diogo P17 Eugenia cf. punicifolia (Kunth) DC. P18 Eugenia excelsa O.Berg P19 Eugenia pistaciifolia DC. P20 Evolvulus sp.1 P21 Fridericia cinerea (Bureau ex K.Schum.) L.G.Lohmann P22 Gymneia sp. 1 (Benth.) Harley & J.F.B.Pastore P23 Herissantia crispa (L.) Brizicky P24 Ipomoea incarnata (Vahl) Choisy P25 Ipomoea sp.1 P26 Jacquemontia sp1. Choisy P27 Lasiolaena lychnophorioides Roque et al. P28 Lepidaploa chalybaea (Mart. ex DC.) H.Rob. P29 Lippia sp.1 P30 Lippia sp.2 P31 Plant Species Code Malpighiaceae sp.1 P32 Manihot sp.1 P33 Microstachys corniculata (Vahl) Griseb. P34 Mikania elliptica DC. P35 Mimosa somnians Humb. & Bonpl. ex Willd. P36 Mimosa sp.1 P37 Moquiniastrum blanchetianum (DC.) G. Sancho P38 Myrtaceae sp.1 P39 Myrtaceae sp.2 P40 Passiflora edmundoi Sacco P41 Passiflora edulis Sims P42 Periandra mediterranea (Vell.) Taub. P43 Piriqueta sidifolia (Cambess.) Urb. P44 Pityrocarpa moniliformis (Benth.) Luckow & R.W.Jobson P45 Rhaphiodon echinus Schauer P46 Senegalia langsdorffii (Benth.) Seigler & Ebinger P47 Senna acuruensis (Benth.) H.S.Irwin & Barneby P48 Senna macranthera (DC. ex Collad.) H.S.Irwin & Barneby P49 Senna macranthera var. micans (Nees) H.S.Irwin & Barneby P50 Serjania faveolata Radlk. P51 Serjania lethalis A.St.-Hil. P52 Serjania sp. 1 P53 Serjania sp. 2 P54 Serjania sp. 3 P55 Simarouba amara Aubl. P56 Stachytarpheta crassifolia Schrad. P57 Stigmaphyllon paralias A.Juss. P58 Stylosanthes scabra Vogel P59 Turnera sp. 1 P60 Urochloa decumbens (Stapf) R.D.Webster P61 Waltheria cf. indica L. P62 Bee species Bee Code Nab Plant species Temnosoma cf. metallicum Smith, 1853 B63 1 P62(1) Halictini Dialictus opacus (Moure, 1940) B32 5 P8(1), P51(1), P58(3) MEGACHILIDAE Anthidiini Dicranthidium sp. 1 B33 1 P3(1) Megachilini Megachile (Pseudocentron) sp. 3 B47 1 P29(1) Megachile sp. 8 B48 1 P51(1)