Fig. 1

Volvocales species/strains used in this study. A Schematic illustration of representative genera in Volvocales. B Phylogenetic relationships among the Volvocalean species examined in this study (Table 1). The cladogram was constructed based on the recent phylotranscriptomics/phylogenomics [8, 9] and the chloroplast multigene phylogeny [10] of homothallic V. africanus and V. zeikusii. Note that Volvox ferrisii includes V. sp. Sagami [11]. C Bright-field images of species/strains in Volvocales used in this study. Note the difference in scale bars. For species other than Volvox, only generic names are shown. For Volvox, abbreviated generic names and specific names are shown. See Table 1 for details