Bee pollen gathering from a few related plant species is a specialisation known as oligolecty. Although it is an extended phenomenon, it has been scarcely explored in oil-collecting bees. At the geographic level, there is little information about oligolecty persistence and also about phenotypic variation of bees related with abiotic factors. We studied the pollen collection specialisation of the oil-collecting bee Chalepogenus cocuccii, its pollination interactions and phenotypic variation across its distribution range, by analyses of pollen loads, field observations and morphometric measurements. Observations and pollen analyses showed that across its distribution range, C. cocuccii preferred Nierembergia flowers not only for oil but also for pollen. We found two bee-morphotypes, though phenotypic variation was not related to abiotic variables. We postulate that C. cocuccii is a narrowly oligolectic species, phenotypically and ecologically specialised in Nierembergia.

中文翻译：

---

专精于采油蜂 Chalepogenus cocuccii 的花粉采集、授粉相互作用和表型变异

从一些相关的植物物种中收集蜂花粉是一种称为寡聚的专业。虽然它是一种扩展现象，但在采油蜜蜂中却鲜有探索。在地理层面上，关于寡聚持续性以及与非生物因素相关的蜜蜂表型变异的信息很少。我们通过花粉负荷分析、实地观察和形态测量研究了采油蜜蜂 Chalepogenus cocuccii 的花粉收集专业化、授粉相互作用和分布范围内的表型变化。观察和花粉分析表明，在其分布范围内，C. cocuccii 更喜欢 Nierembergia 花，不仅用于油，而且还用于花粉。我们发现了两种蜜蜂形态型，尽管表型变异与非生物变量无关。