Fig. 3

FISH observations of a Rainbow R. exoculata branchiostegite with epibionts. All cells are labeled with DAPI (blue). Zetaproteobacteria are hybridized with the Zeta123 probe (red) [43]. a Zetaproteobacteria are closely attached to the cuticle. Dominant large filamentous bacteria (Campylobacteria) and thinner Gammaproteobacteria filaments can be seen. b Co-hybridization of filamentous Campylobacteria with the EPSI 549 probe (orange) [44] and small Zetaproteobacteria rods (red), highlighting the co-occurrence of both lineages