Reassessment of the classification of Bryopsidales (Chlorophyta) based on chloroplast phylogenomic analyses

Abstract

The Bryopsidales is a morphologically diverse group of mainly marine green macroalgae characterized by a siphonous structure. The order is composed of three suborders - Ostreobineae, Bryopsidineae, and Halimedineae. While previous studies improved the higher-level classification of the order, the taxonomic placement of some genera in Bryopsidineae (Pseudobryopsis and Lambia) as well as the relationships between the families of Halimedineae remains uncertain. In this study, we re-assess the phylogeny of the order with datasets derived from chloroplast genomes, drastically increasing the taxon sampling by sequencing 32 new chloroplast genomes. The phylogenies presented here provided good support for the major lineages (suborders and most families) in Bryopsidales. In Bryopsidineae, Pseudobryopsis hainanensis was inferred as a distinct lineage from the three established families allowing us to establish the family Pseudobryopsidaceae. The Antarctic species Lambia antarctica was shown to be an early-branching lineage in the family Bryopsidaceae. In Halimedineae, we revealed several inconsistent phylogenetic positions of macroscopic taxa, and several entirely new lineages of microscopic species. A new classification scheme is proposed, which includes the merger of the families Pseudocodiaceae, Rhipiliaceae and Udoteaceae into a more broadly circumscribed Halimedaceae, and the establishment of tribes for the different lineages found therein. In addition, the deep-water genus Johnson-sea-linkia, currently placed in Rhipiliopsis, was reinstated based on our phylogeny.

A new marine prasinophyte genus alternates between a flagellate and a dominant benthic stage with microrhizoids for adhesion

“…To obtain data for chloroplast genome assembly, paired‐end libraries were constructed and sequenced with Illumina technology following methods described by Cremen et al. (, ). For strain T39, we used the HiSeq 2500 platform (paired‐end, 125 reads, ~3 Gb of data) and for 5FNG, we used the NextSeq 500 platform (paired‐end, 150 bp reads, ~1.5 Gb of data).…”

“…The 18S rRNA gene was amplified and sequenced as described in Wetherbee and Verbruggen (2016) and the sequences submitted to Genbank (MN056945-8). To obtain data for chloroplast genome assembly, paired-end libraries were constructed and sequenced with Illumina technology following methods described by Cremen et al (2018Cremen et al ( , 2019. For strain T39, we used the HiSeq 2500 platform (paired-end, 125 reads,~3 Gb of data) and for 5FNG, we used the NextSeq 500 platform (paired-end, 150 bp reads,~1.5 Gb of data).…”

Comprehensive Analysis of Rhodomyrtus tomentosa Chloroplast Genome

“…In addition, the nucleotide evolution rate of the chloroplast genome is moderate. This has allowed chloroplast genomes to be used for phylogenetic studies at different taxonomic levels [11]. The first chloroplast genome was successfully obtained from Nicotiana tabacum [12].…”

Diversity of Sulfated Polysaccharides From Cell Walls of Coenocytic Green Algae and Their Structural Relationships in View of Green Algal Evolution

“…The Bryopsidales consist of three main clades, corresponding to the suborders Bryopsidineae, Halimedineae, and Ostreobineae ( Figure 3 ), which are characterized based on differences in thallus morphology, reproduction and plastid types ( Hillis-Colinvaux, 1984 ; Cremen et al, 2019 ).…”

“… Phylogenetic relationships of the families and suborders of the Bryopsidales (based on Cremen et al, 2019 ). The genera for which data on sulfated polysaccharides is available, and which are discussed in this review, are underlined.…”