Wikipedia
Caldithrix
Caldithrix is a genus of thermophilic and anaerobic bacterium that are difficult to assign to any particular Eubacterial phyla. According to 'The All-Species Living Tree' Project Caldithrix is a member of Sphingobacteria, whereas the LPSN assigns it as an unclassified Deferribacterales and the NCBI considers it an unclassified Bacteria.