Rahnella
aquatilis

Ralstonia
insidiosa - mannitolilytica - pickettii - solanacearum - sp. - syzygii

Ramlibacter
henchirensis - tataouinensis

Raoultella
planticola - terrigena

Rathayibacter
iranicus - rathayi - sp. - tritici

Renibacterium
salmoninarum

Rheinheimera
baltica

Rhizobacter
dauci

Rhizobium
etli - galegae - huautlense - larrymoorei - leguminosarum - mongolense - radiobacter - rhizogenes - rubi - sp. - tropici - undicola - vitis - yanglingense

Rhizomonas
sp.

Rhodobacter
blasticus - capsulatus - sphaeroides

Rhodoblastus
acidophilus

Rhodococcus
coprophilus - equi - erythropolis - fascians - rhodnii - rhodochrous - ruber - sp. - wratislaviensis

Rhodocyclus
purpureus - tenuis

Rhodomicrobium
vannielii

Rhodopila
globiformis

Rhodopseudomonas
palustris

Rhodospirillum
photometricum - rubrum

Rhodovulum
sulfidophilum

Riemerella
anatipestifer - columbina

Roseivirga
ehrenbergii

Roseobacter
litoralis

Rubrivivax
gelatinosus

Ruegeria
algicola

Runella
slithyformis - zeae