Fragmentation of the Atlantic Forest negatively impacts the population dynamics of native pollinators in these environments, especially that of stingless bees. Meanwhile, stingless bees contribute to the self-regeneration of vegetation and the sustainability of agriculture through pollination services. Thus, studies of the floral sources exploited by bees are essential for the development of conservation strategies for the associated flora and fauna. The present study represents the first palynological characterization of the stored pollen of Frieseomelitta meadewaldoi (Cockerell, 1915) in an area of Atlantic Forest, with the objective of determining the important plant species in the composition of trophic resources of the colonies of these bees. A total of 19 monthly samples were collected in three colonies during the period of April 2013 to March 2014. After processing by acetolysis, pollen types were identified and at least 1000 pollen grains were counted. Pollen morphology was described for the most representative pollen types. Microscopic analysis revealed the presence of 39 pollen types, distributed in 20 families, three of which were indeterminate. Pollen types of the families Fabaceae, Gentianaceae, Loranthaceae, Malvaceae, Rutaceae, Sapindaceae, Urticaceae, and Violaceae were prominent. Among the pollen types found, Waltheria, Dioclea, and Schultesia contributed the most to the pollen spectrum of F. meadewaldoi, which reveals it to have a generalist behavior but with concentrated foraging on some particular plant species, which indicates potential key plants for the maintenance of this species in nature.

大西洋森林的破碎化对这些环境中本地传粉媒介的种群动态产生了负面影响，尤其是无刺蜂。与此同时，无刺蜜蜂通过授粉服务促进植被的自我再生和农业的可持续性。因此，对蜜蜂利用的花卉来源的研究对于制定相关动植物群的保护策略至关重要。本研究代表了Frieseomelitta meadewaldoi储存花粉的第一个孢粉学特征（Cockerell，1915）在大西洋森林地区，目的是确定这些蜜蜂群落营养资源组成中的重要植物物种。2013年4月至2014年3月期间，在三个群体中总共采集了19个月度样品。经过丙酮水解处理后，鉴定了花粉类型，并对至少1000个花粉粒进行了计数。描述了最具代表性的花粉类型的花粉形态。显微镜分析显示存在 39 种花粉类型，分布在 20 个科中，其中 3 个是不确定的。豆科、龙胆科、桑寄生科、锦葵科、芸香科、无患子科、荨麻科和堇菜科的花粉类型最为突出。在发现的花粉类型中，Waltheria、Dioclea和Schultesia对F. meadewaldoi的花粉谱贡献最大，这表明它具有通用行为，但集中在某些特定植物物种上觅食，这表明在自然界中维持该物种的潜在关键植物。