Assessment of genetic diversity and population structure of Eulaema nigrita (Hymenoptera: Apidae: Euglossini) as a factor of habitat type in Brazilian Atlantic forest fragments

In many organisms, habitat affects ecological and genetic diversity and, for certain species, it is expected that a large population should have higher genetic diversity than a smaller population. We analysed the genetics of males of the orchid bee, Eulaema nigrita (Hymenoptera: Apidae), and examined the links between local abundance and habitat with genetic diversity. We also investigated the impact of landscape features on genetic population structure, through microsatellite and mitochondrial DNA analysis, among populations found across 700 km of Brazilian Atlantic forest fragments. We found that genetic variation was not a function of local abundance, but it correlated significantly with habitat. There was significant but low genetic differentiation among populations. We found a single mitochondrial DNA haplotype in all sequenced specimens, which may be widespread throughout the Atlantic forest. Our results reinforce the idea that orchid bees can fly long distances. High-dispersal ca...

在诸多生物类群中，生境会对其生态与遗传多样性产生影响；针对特定物种，通常认为种群规模更大的群体，其遗传多样性水平会高于种群规模较小的群体。我们针对兰花蜂（orchid bee）物种黑丽兰蜂（Eulaema nigrita，膜翅目（Hymenoptera）：蜜蜂科（Apidae））的雄性个体开展遗传学分析，探究了当地种群丰度、生境与遗传多样性之间的关联。此外，我们通过微卫星（microsatellite）与线粒体DNA（mitochondrial DNA）分析技术，对分布于巴西大西洋森林700公里范围内的多个种群进行研究，探讨了景观特征对种群遗传结构的影响。研究结果表明，遗传变异与当地种群丰度并无关联，但与生境存在显著相关性。种群间存在显著但程度较低的遗传分化。我们在所有测序样本中仅发现一种线粒体DNA单倍型（haplotype），该单倍型可能广泛分布于大西洋森林区域。本研究结果进一步佐证了兰蜂具备长距离飞行能力的论断，其扩散能力极强（High-dispersal ca...）