Thermithiobacillus
（重定向自Thermithiobacillaceae）
Thermithiobacillus is a genus of non-sporeforming, rod-shaped, Gram-negative proteobacteria. The name derives from the Latin thermae, for warm baths, and the Greek θείος, theios for sulfur. The members of this genus used to belong to Thiobacillus, before they were reclassified on the basis of 16S rRNA analysis in 2000. A phylogenetic analysis, using 98 protein families confirmed this reassignment. This chemolithoautotrophic genus is obligately aerobic and moderately thermophilic (43-45°C). Only one species of this genus is known (Thermithiobacillus tepidarius).