Fig. 4: Distribution of Candidatus Tectiglobus diatomicola and other N₂ fixers in the world’s oceans.

a, Distribution of Ca. T. diatomicola (pink circles) and Ca. T. profundi (black circles) based on read detection in metagenome datasets from Tara Oceans and our own samples (see Methods and Supplementary Table 4). Black-and-pink circles are metagenomes in which both Ca. Tectiglobus species were detected. The abundance of Ca. T. diatomicola on the basis of gamma-A-specific nifH qPCR data is shown (circles in blue-to-yellow gradient; data from a previous study⁸). Sample locations in which gamma-A nifH qPCR counts were zero are shown in Extended Data Fig. 5b. b, Proportion of heterotrophic (orange) versus cyanobacterial (cyan) N₂ fixers identified in a previous study⁵ (0.8–2,000 µm size fraction) in metagenome datasets from Tara Oceans.