Pantocsekiella comensis is ubiquitous in the Laurentian Great Lakes and is an important indicator of climate change and low nutrients. Pantocsekiella comensis forms a diverse complex with high morphological diversity. We distinguished three species within the complex: P. comensis, Pantocsekiella delicatula, and Pantocsekiella laurentiana sp. nov. by examining specimens from the Great Lakes using light and scanning electron microscopy. All species have radial, uniform, and alveolate striae, a central fultoportula, a rimoportula opposite the central fultoportula, and marginal fultoportulae. However, P. laurentiana has a smaller diameter than P. comensis (4–8 µm vs. 4–12 µm) and orbiculi depressi on half its tangentially undulated centre. Pantocsekiella delicatula has a distinct central fultoportula and colliculate centre, and lacks the orbiculi depressi and tangential undulation of P. comensis and P. laurentiana. Its diameter (4–14 µm) is generally larger than that of P. comensis. A multiple factor analysis based on morphological features, in addition to environmental characteristics, confirmed the separation of these species. The presence of transitional specimens with features of two or more of these species complicated classification; however, these occurrences were rare, and differentiation was usually possible.

中文翻译：

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劳伦斯大湖 Pantocsekiella comensis 复合体周围的形态变异

Pantocsekiella comensis 在劳伦斯五大湖中无处不在，是气候变化和低营养的重要指标。Pantocsekiella comensis 形成具有高度形态多样性的多样化复合体。我们在复合物中区分了三个物种：P. comensis、Pantocsekiella delicatula 和 Pantocsekiella laurentian sp。十一月 通过使用光学和扫描电子显微镜检查来自五大湖的标本。所有物种都有放射状的、均匀的和蜂窝状的条纹、中央的 fultoportula、与中央 fultoportula 相对的 rimoportula 和边缘的 fultoportulae。然而，P. laurentiana 的直径比 P. comensis 小（4-8 µm 与 4-12 µm），并且在其切线起伏中心的一半处有凹陷的轮匝菌。Pantocsekiella delicatula 具有明显的中央 fultoportula 和丘状中心，并且缺乏P. comensis 和P. laurentiana 的凹陷和切线起伏。它的直径 (4–14 µm) 通常大于 P. comensis 的直径。除了环境特征外，基于形态特征的多因素分析证实了这些物种的分离。具有两个或多个这些物种复杂分类特征的过渡标本的存在；然而，这些情况很少见，通常可以区分。具有两个或多个这些物种复杂分类特征的过渡标本的存在；然而，这些情况很少见，通常可以区分。具有两个或多个这些物种复杂分类特征的过渡标本的存在；然而，这些情况很少见，通常可以区分。