negativicoccus negativicoccus negativicoccus is a gram-negative and anaerobic genus of bacteria from the family of veillonellaceae. negativicoccus scientific classification domain: bacteria phylum: bacillota class: negativicutes order: veillonellales family: veillonellaceae genus: negativicoccusmarchandin et al. 2010 type species negativicoccus succinicivorans species n. succinicivorans n. massiliensis