Based on comparative analysis of 16S rRNA sequences and the recently established phylogeny of the genus Desulfotomaculum , a set of phylogenetically nested hybridization probes was developed and characterized. A genus‐specific probe targets all known Desulfotomaculum species (with the exception of Desulfotomaculum acetoxidans ), and five specific probes target subclusters within the Desulfotomaculum genus. The dissociation tem...