RNA sequencing and de novo transcriptome assembly of the bluestreak cleaner wrasse (Labroides dimidiatus) and the powder blue surgeonfish (Acanthurus leucosternon) used to characterize the molecular signatures of their mutualistic behaviour under normal and climate change conditions (ocean warming and acidification). We investigated the patterns of differential gene expression across the three main regions of the brain of each species: Forebrain (FB), Midbrain (MB) and Hindbrain (HB), to understand the underlying molecular processes and neural pathways activated during their social interaction.