ABSTRACT
The bacteria that cause necrotizing hepatopancreatitis in
Penaeus vannamei
adversely affect penaeid shrimp cultured in the western hemisphere. 16S rRNA and gyrase B gene analyses determined the taxonomic position of these bacteria. The name “
Candidatus
Hepatobacter penaei” is proposed for these pathogenic bacteria, which are members of the
Rickettsiales
order.