the root (no rank)
Bacteria (domain)
Firmicutes (phylum)
Bacilli (class)
Lactobacillales (order)
Streptococcaceae (family)
Streptococcus (genus)
oral streptococci (subgenus)
[hide inferior taxa]
Streptococcus mutans (species)
Streptococcus sobrinus (species)