[2][3][4][5] One extant species Kelletia lischkei occurs in the Sea of Japan off the coasts of Japan and South Korea, and another K. kelletii is found of along the coasts of California, United States and in the Baja California, Mexico.
[15] A molecular phylogeny of Buccinidae based on the mitochondrial 16S rRNA gene suggested that Kelletia is a closely related to Penion, a whelk genus with extant species distributed in waters off of New Zealand and Australia.
[6] Results of a further molecular phylogenetic studies using mitochondrial genomic and nuclear ribosomal DNA sequence data re-affirmed this relationship, and also demonstrated that Kelletia and Antarctoneptunea found in the southern Pacific and Southern oceans are closely related.
[2][4][5] The common ancestor of the three genera most likely evolved in the southern Pacific Ocean, and a lineage leading to Kelletia dispersed over millions of years up the western coast of the Americas into the northern Pacific Ocean.
[16] Antarctoneptunea Kelletia Penion Serratifusus Aeneator Buccinulum Euthria Tasmeuthria