Microbiology Bacteria bf59bc69 Gravis, Intermedius and Mitis are biotypes of: A Clostridium perfringens B Corynebacterium diphtheria C Capnocytophaga D Klebsiella High-Yield Explanation Ans. B. Corynebacterium diphtheriaGravis, Intermedius, Mitis and Belfanti are biotypes of Corynebacterium diphtheria. Gravis causes most severe disease.