We performed a comparison of molecular and morphological diversity in a freshwater colonial genus Synura (Chrysophyceae, Stramenopiles), using the island of Newfoundland (Canada) as a case study. We examined the morphological species diversity in collections from 79 localities, and compared these findings to diversity based on molecular characters for 150 strains isolated from the same sites. Of 27 species or species‐level lineages identified, only one third was recorded by both molecular and morphological techniques, showing both approaches are complementary in estimating species diversity within this genus. Eight taxa, each representing young evolutionary lineages, were recovered only by sequencing of isolated colonies, whereas ten species were recovered only microscopically. Our complex investigation, involving both morphological and molecular examinations, indicates that our knowledge of Synura diversity is still poor, limited only to a few well‐studied areas. We revealed considerable cryptic diversity within the core S. petersenii and S. leptorrhabda lineages. We further resolved the phylogenetic position of two previously described taxa, S. kristiansenii and S. petersenii f. praefracta, propose species‐level status for S. petersenii f. praefracta, and describe three new species, S. vinlandica, S. fluviatilis, and S. cornuta. Our findings add to the growing body of literature detailing distribution patterns observed in the genus, ranging from cosmopolitan species, to highly restricted taxa, to species such as S. hibernica found along coastal regions on multiple continents. Finally, our study illustrates the usefulness of combining detailed morphological information with gene sequence data to examine species diversity within chrysophyte algae.

中文翻译：

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比较淡水Synura（Stramenopiles）物种多样性的形态学和分子估计：理解真核微生物多样性的模型。

我们进行了淡水殖民地Synura属的分子和形态多样性的比较（金藻科，Stramenopiles），以纽芬兰岛（加拿大）为例。我们检查了来自79个地点的集合中的形态物种多样性，并将这些发现与基于分子特征从同一地点分离的150个菌株的多样性进行了比较。在鉴定出的27个物种或物种水平谱系中，只有三分之一的分子和形态学技术被记录下来，表明这两种方法在估计该属的物种多样性方面是互补的。仅通过对分离的菌落进行测序，即可回收到八个分类单元，每个分类单元都代表年轻的进化谱系，而仅在显微镜下可以回收十个物种。我们的复杂调查涉及形态学和分子检查，这表明我们对Synura的了解多样性仍然很差，仅限于几个经过充分研究的领域。我们发现核心S. petersenii和S. leptorrhabdada谱系中存在大量隐秘的多样性。我们进一步解决了两个先前描述的类群，S。kristiansenii和S. petersenii f的系统发生位置。praefracta，提出S. petersenii f。的物种水平状态。praefracta，并描述新种，S. vinlandica，S. fluviatilis，和S.枸骨。我们的发现增加了越来越多的文献，详细介绍了该属中观察到的分布模式，从世界性物种到高度受限制的分类单元，再到在多大洲沿海地区发现的S. hibernica等物种。最后，我们的研究说明了将详细的形态学信息与基因序列数据相结合来检查金藻藻类内物种多样性的有用性。