Hi John,
Genetic analysis has indeed been done on the tigris complex by Dr. 
Christopher Meyer. As discussed in the last edition of the Cowries Guide 
by F. Lorenz, three of the four subspecies recognized in that work show 
significant genetic differences while the fourth is recognized by 
conchological features and geographic isolation (see the excerpt below 
from the book.) The four subspecies are:
Cypraea tigris tigris (Linnaeus 1758),
C. tigris pardalis Shaw 1795,
C. tigris schilderiana Cate 1961,
C. tigris lorenzi Meyer & Tweedt 2017.
 From the Guide:
"This variable and widespread species is split into three subspecies 
which are well supported genetically, but difficult to distinguish 
conchologically. The Indian Ocean is inhabited by the nominate tigris, 
while along the border between the Eastern Indian Ocean and the Pacific, 
interbreeding with the Pacific pardalis takes place. There is no way to 
safely distinguish shells from the Indian Ocean and the western Pacific. 
The Hawaiian schilderiana is here considered a subspecies because of 
subtle but relatively constant shell differences. A third, genetically 
and conchologically distinct population is found in the Marquesas 
(lorenzi)."

For those of us that study the cowries, most of the additional tigris 
taxa named in the last couple of years are considered variations with no 
taxonomic value.
I hope this helps,
Randy Bridges

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