Crustose coralline algae that promote coral larval settlement harbor distinct surface bacterial communities

Crustose coralline algae (CCA) can induce settlement and metamorphosis responses in many invertebrates including corals. We tested the respective coral settlement capacity of multiple CCA species in a choice experiment and investigated the composition of their microbiomes. Our findings revealed that coral larval settlement was drastically influenced by CCA phylogeny, but also indicated the role of distinct bacterial community compositions on CCA surfaces as a driver of coral larval settlement.