Revision of the phycoerythrin 545-containing cryptophytes

隐藻科主要由光合鞭毛虫组成，它们成功地征服了海洋和淡水栖息地。它们在生态学上是重要的，是一些浮游捕食者（如螯合动物、桡足动物或鞭毛动物）的猎物。虽然由于其独特的性状组合可以很容易地识别，但二态性和缺乏种特有的形态特征在较低的分类水平上造成了识别问题。这导致了系统的不一致，严重损害了隐生植物分类群的生物多样性调查。本项目旨在建立一个以海洋植红蛋白545为主的隐生植物属的完整系统。所有检查均以克隆株为基础。为了研究隐种谱系之间的关系，系统发育树是从两个基因组，核和核形态的核糖体DNA序列的组合数据集推断出来的。通过将形态特征映射到系统发育树上，可以识别属或种特有的特征。由于在隐植体培养中不能诱导有性生殖，因此核糖体操纵子内部转录间隔2的补偿碱基对变化将被用作预测假定生物物种的间接标记。分类学修订包括分子特征作为诊断特征，以允许鉴定遗传上不同，但形态上模糊的分类群。

The Cryptophyceae consist predominantly of photosynthetic flagellates that successfully conquered marine as well as freshwater habitats. They are ecologically important as prey for several planktic predators (e.g. clliate, copepod or dinoflagellate species). Although cryptophytes as such can be easily identified due to a unique combination of characters, dimorphisms and a lack of species-specific morphological characters cause problems in identification at lower classification levels. This resulted in an inconsistent systematic seriously compromising biodiversity surveys of cryptophyte taxa. This project aims at establishing a sound systematics of the predominantly marine phycoerythrin 545-containing cryptophyte genera. All examinations are based on clonal strains. To examine relationships among the cryptophyte lineages, phylogenetic trees are inferred from combined data sets of ribosomal DNA sequences of two genomes, nucleus and nucleomorph. By mapping morphological characters onto phylogenetic trees, genus- or species-specific characters can be identified. Since sexual reproduction cannot be induced in cryptophyte cultures, compensating base pair changes in the internal transcribed spacer 2 of the nuclear ribosomal operon will be used as indirect markers to predict putative biological species. The taxonomic revisions include molecular signatures as diagnostic characters to allow for an identification of genetically distinct but morphologically ambiguous taxa.