Aerial green algae of Trentepohliaceae can form conspicuous free-living colonies, be parasites of plants or photobionts of lichen-forming ascomycetes. So far, their diversity in temperate regions is still poorly known as it has been mostly studied by phenotypic approaches only. We present new insights in the phylogenetic relationships of lichenized representatives from temperate and Mediterranean parts of Europe by analysis of 18S rRNA and rbcL gene fragments, and nuclear ITS sequence data. For this purpose we isolated the trentepohlialean photobionts from lichens representing different genera. Algal cultures from lichenized and free-living Trentepohliaceae were used to design new primers for amplification of the marker loci. We constructed a phylogenetic hypothesis to reveal the phylogenetic placements of lichenized lineages with 18S rRNA and rbcL sequences. ITS variation among the clades was substantial and did not allow including them in the general phylogenetic assessment, yet ITS appears to be a promising marker for DNA-barcoding approaches. Specific algae were found in particular lichen but the overall diversity of photobionts was limited. The multilocus tree does not support the current morphological classification of genera in Trentepohliaceae, suggesting that morphology is more variable than previously thought in this group of algae.

中文翻译：

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对温带地衣光生物多样性和选择性的新见解。


空中的特伦特波利亚科绿藻可以形成明显的自由生活菌落，是植物的寄生虫或形成地衣的子囊菌的光合生物。到目前为止，人们对它们在温带地区的多样性仍然知之甚少，因为大多数情况下仅通过表型方法进行研究。通过分析 18S rRNA 和rbc L 基因片段以及核 ITS 序列数据，我们对欧洲温带和地中海地区地衣化代表的系统发育关系提出了新的见解。为此，我们从代表不同属的地衣中分离出了特伦特波利亚光生物素。来自地衣和自由生活的特伦特波利亚科的藻类培养物被用来设计用于扩增标记基因座的新引物。我们构建了一个系统发育假说，以揭示具有 18S rRNA 和rbc L 序列的地衣化谱系的系统发育位置。进化枝之间的 ITS 变异很大，不允许将它们纳入一般系统发育评估中，但 ITS 似乎是 DNA 条形码方法的一个有前途的标记。在特定的地衣中发现了特定的藻类，但光生物素的总体多样性有限。多位点树不支持当前 Trentepohliaceae 属的形态分类，这表明该藻类的形态比以前认为的更加多变。