The marine environment contains a large diversity of sulfated polysaccharides and other glycopolymers. Saccharolytic microorganisms degrade these compounds through hydrolysis, which includes the hydrolysis of sulfate groups from sugars by sulfatases. Various marine bacteria of the Planctomycetes-Verrucomicrobia-Chlamydia (PVC) superphylum have exceptionally high numbers of sulfatase genes associated with the degradation of sulfated polysaccharides. However, until this study, no sulfatase-rich marine anaerobes were known. Using fucoidan as substrate, we isolated and characterized two anaerobic bacteria from Kiritimatiellaeota clade R76-B128. Based on phylogenetic and chemotaxonomic analyses, we proposed the taxa Pontiella desulfatans F1T gen. nov., sp. nov. and Pontiella sulfatireligans F21T sp. nov. as representatives of the Pontiellaceae fam. nov. within the class Kiritimatiellae. These bacteria encode unprecendently high numbers of CAZymes and sulfatases in their genomes.