Figure 14 in The search finds an end: the morphologically chimeric hysterocinetids belong to the subclass Hymenostomatia (Ciliophora: Oligohymenophorea)

Figure 14. Secondary structure of the C, 3ʹM and 3ʹm domains of the 16S rRNA molecule of Hysterocineta bellerophon. Arrows mark molecular synapomorphies of the 'paravorax' clade. Similarly to the homologous nuclear 18S, molecular synapomorphies are distributed across the whole 16S rRNA molecule: 13 nucleotides in the C domain, seven in the 3'M domain, and two in the 3'm domain. Thus, 'paravorax' cladespecific nucleotide characters are situated in terminal loops of helices (three nucleotide positions), bulges and single-stranded regions (seven positions), as well as in the double-stranded regions (12 positions). As in 18S and 28S, many more mutations are involved in Watson‒Crick and wobble pairings than in non-canonical interactions in the double-stranded regions of the 16S rRNA molecule. The 16S secondary structure map of Escherichia coli (inset) is from hưp://apollo.chemistry.gatech.edu/RibosomeGallery.