 While toxic species of "Dinophysis" such as "D. acuminata" have a single gene for LSU rRNA, non-toxic species seem to have two distinct classes of LSU rRNA.The difference between these two classes was a 70 bp deletion, indicating the shorter product might be a pseudogene.The pseudogene can be used as a marker of "D. acuminata" and might conveniently serve as a marker of toxic and non-toxic strains and bring more insight to the genetics of toxicity of "Dinophysis".