Photobacterium histaminum Okuzumi et al. 1994 is a later subjective synonym of Photobacterium damselae subsp. damselae (Love et al. 1981) Smith et al. 1991

The type strain of Photobacterium histaminum, JCM 8968(T) (=ATCC 51805(T)), and that of Photobacterium damselae subsp. damselae, ATCC 33539(T), exhibit 100% identity in their 16S rRNA sequence, more than 80% DNA--DNA homology and only one phenotypic difference. Also, like P. histaminum, P. damselae subsp. damselae was shown to excrete a large amount of histamine when cells were grown on medium containing excessive histidine under acidic conditions. Therefore, the name P. histaminum should be considered to be a later subjective synonym of P. damselae subsp. damselae.