<i>Candidatus</i> Renichlamydia lutjani, a Gram-negative bacterium in internal organs of blue-striped snapper <i>Lutjanus kasmira</i> from Hawaii

The blue-striped snapper <i>Lutjanus kasmira</i> (Perciformes, Lutjanidae) are cosmopolitan in the Indo-Pacific but were introduced into Oahu, Hawaii, USA, in the 1950s and have since colonized most of the archipelago. Studies of microparasites in blue-striped snappers from Hawaii revealed chlamydia-like organisms (CLO) infecting the spleen and kidney, characterized by intracellular basophilic granular inclusions containing Gram-negative and Gimenez-positive bacteria similar in appearance to epitheliocysts when seen under light microscopy. We provide molecular evidence that CLO are a new member of <i>Chlamydiae</i>, i.e. <i>Candidatus</i> Renichlamydia lutjani, that represents the first reported case of chlamydial infection in organs other than the gill in fishes.