Correction to: Phylogeny resolved, metabolism revealed: functional radiation within a widespread and divergent clade of sponge symbionts

We have recently become aware that the taxonomic names published in our article Tayler et al. ISME J 2021; 15:503–519 do not comply with standards set out by the International Committee on Systematics of Prokaryotes (ICSP) as we used a “superscript U” instead of the term “Candidatus”. We followed the guidelines by Konstantinidis et al. (Uncultivated microbes in need of their own taxonomy. ISME J. 2017;11:2399–406) which suggested the use of “superscript U”, but I have been informed that the guidelines have not received widespread acceptance. The taxonomic names should be as summarised in the corrected Table S5 below: The original article has been corrected.