@article {kawachi_rappemonads_2021,
	title = {Rappemonads are haptophyte phytoplankton},
	journal = {Current Biology},
	year = {2021},
	month = {mar},
	abstract = {Rapidly accumulating genetic data from environmental sequencing approaches have revealed an extraordinary level of unsuspected diversity within marine phytoplankton,1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 which is responsible for around 50\% of global net primary production.12,13 However, the phenotypic identity of many of the organisms distinguished by environmental DNA sequences remains unclear. The rappemonads represent a plastid-bearing protistan lineage that to date has only been identified by environmental plastid 16S rRNA sequences.14, 15, 16, 17 The phenotypic identity of this group, which does not confidently cluster in any known algal clades in 16S rRNA phylogenetic reconstructions,15 has remained unknown since the first report of environmental sequences over two decades ago. We show that rappemonads are closely related to a haptophyte microalga, Pavlomulina ranunculiformis gen. nov. et sp. nov., and belong to a new haptophyte class, the Rappephyceae. Organellar phylogenomic analyses provide strong evidence for the inclusion of this lineage within the Haptophyta as a sister group to the Prymnesiophyceae. Members of this new class have a cosmopolitan distribution in coastal and oceanic regions. The relative read abundance of Rappephyceae in a large environmental barcoding dataset was comparable to, or greater than, those of major haptophyte species, such as the bloom-forming Gephyrocapsa huxleyi and Prymnesium parvum, and this result indicates that they likely have a significant impact as primary producers. Detailed characterization of Pavlomulina allowed for reconstruction of the ancient evolutionary history of the Haptophyta, a group that is one of the most important components of extant marine phytoplankton communities.},
	keywords = {environmental DNA sequences, morphological evolution, organellar phylogenomics, phytoplankton diversity, RCC3430, transmission electron microscopy},
	issn = {0960-9822},
	doi = {10.1016/j.cub.2021.03.012},
	url = {https://www.sciencedirect.com/science/article/pii/S0960982221003511},
	author = {Kawachi, Masanobu and Nakayama, Takuro and Kayama, Motoki and Nomura, Mami and Miyashita, Hideaki and Bojo, Othman and Rhodes, Lesley and Sym, Stuart and Pienaar, Richard N. and Probert, Ian and Inouye, Isao and Kamikawa, Ryoma}
}
@article {Kamikawa2015,
	title = {Multiple losses of photosynthesis in Nitzschia (Bacillariophyceae)},
	journal = {Phycological Research},
	volume = {63},
	year = {2015},
	note = {tex.mendeley-tags: rcc},
	pages = {19{\textendash}28},
	abstract = {In order to obtain insights into the evolution of colorless (apochlorotic) diatoms, we investigated newly established apochlorotic strains of Nitzschia spp. using light and electron microscopy and molecular phylogenetic analyses. Fluores- cence microscopic observations demonstrated that the apochlorotic diatoms lack chlorophylls. Transmission electron microscopy of two apochlorotic strains also demonstrated that their plastids lacked thylakoids; instead, having four- membrane-bound organelles without thylakoids, similar to nonphotosynthetic plastid remnants. From the apochlorotic strains, we also found plastid small subunit rRNA genes that were unusually long branched in phylogenetic analyses, as observed in other nonphotosynthetic plastids. Molecular phylogenetic analysis of the nucleus-encoded large subunit rRNA genes showed eight distinct lineages for apochlo- rotic diatoms. The eight apochlorotic lineages were not monophyletic, suggesting that the loss of photosynthesis took place multiple times independently within Nitzschia. Several diatoms, including Nitzschia spp., are mixotrophic, which is an expected mode of nutrition that would help explain the evolutionary switch from a photosynthetic lifestyle to a heterotrophic lifestyle. Key},
	keywords = {apochlorotic diatoms, genetic diversity, large subunit rrna, molecular phylogenetic analysis, nonphotosynthetic plastids, plastid 16s rrna, rcc},
	issn = {13220829},
	doi = {10.1111/pre.12072},
	url = {http://doi.wiley.com/10.1111/pre.12072},
	author = {Kamikawa, Ryoma and Yubuki, Naoji and Yoshida, Masaki and Taira, Misaka and Nakamura, Noriaki and Ishida, Ken-ichiro and Leander, Brian S. and Miyashita, Hideaki and Hashimoto, Tetsuo and Mayama, Shigeki and Inagaki, Yuji}
}
