Table_1_Characterization and Comparison of Convergence Among Cephalotus follicularis Pitcher Plant-Associated Communities With Those of Nepenthes and Sarracenia Found Worldwide.xlsx

The Albany pitcher plant, Cephalotus follicularis, has evolved cup-shaped leaves and a carnivorous habit completely independently from other lineages of pitcher plants. It is the only species in the family Cephalotaceae and is restricted to a small region of Western Australia. Here, we used metabarcoding to characterize the bacterial and eukaryotic communities living in C. follicularis pitchers at two different sites. Bacterial and eukaryotic communities were correlated in both richness and composition; however, the factors associated with richness were not the same across bacteria and eukaryotes, with bacterial richness differing with fluid color, and eukaryotic richness differing with the concentration of DNA extracted from the fluid, a measure roughly related to biomass. For turnover in composition, the variation in both bacterial and eukaryotic communities primarily differed with fluid acidity, fluid color, and sampling site. We compared C. follicularis-associated community diversity with that of Australian Nepenthes mirabilis, as well as a global comparison of Southeast Asian Nepenthes and North American Sarracenia. Our results showed similarity in richness with communities from other pitcher plants, and specific bacterial taxa shared among all three independent lineages of pitcher plants. Overall, we saw convergence in richness and particular clades colonizing pitcher plants around the world, suggesting that these highly specialized habitats select for certain numbers and types of inhabitants.

阿尔巴尼捕蝇草，学名 Cephalotus follicularis，系独立于其他捕蝇草类群进化而来，拥有杯状叶片和捕食习性。该物种为 Cephalotaceae 科唯一成员，其分布局限于澳大利亚西部一小区域。本研究采用元条形码技术，对生活在 C. follicularis 捕蝇草两个不同地点的细菌和真核生物群落进行了表征。细菌和真核生物群落不仅在丰富度上，而且在组成上亦呈相关性；然而，与细菌和真核生物丰富度相关的因素并非一致，细菌丰富度与流体颜色相关，而真核生物丰富度则与从流体中提取的 DNA 浓度相关，该浓度可近似反映生物量。在组成动态变化方面，细菌和真核生物群落的变化主要与流体酸度、流体颜色以及采样地点相关。我们将 C. follicularis 相关群落多样性与其他捕蝇草物种，如澳大利亚 Nepenthes mirabilis，以及东南亚 Nepenthes 与北美 Sarracenia 的全球对比进行了研究。结果显示，与其他捕蝇草群落具有相似丰富度，且三个独立捕蝇草类群中存在共享的特定细菌分类单元。总体而言，我们在丰富度和全球捕蝇草周围特定群落侵入的特定分支上观察到趋同现象，这表明这些高度专业化的生境倾向于选择特定的居民数量和类型。