Figure 1.

The enormous diversity of algae contrasts with their poorly characterized viromes. (A) Representation of algae supergroups among the diversity of eukaryotes (latest eukaryotic classification retrieved from [29]). The phylogenetic tree was adapted from [56]. Pictures illustrate some of the samples used in this study and corresponding clades are marked with “*”. (B) Pictures of algae cultures used in this study. (C) The current extent of the microalgae virosphere. The viral sequence counts for each virus class (DNA or RNA, single-stranded or double-stranded) were retrieved from VirusHostdb [16] according to 11 major eukaryotic algae lineages. Microalgal lineages investigated in this study are highlighted in bold.