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It is there on the pages 40 and 41 as Crenavolva tigris (Adams & Reeve, 1848), I changed the genus according to WoRMS.
Species of the family Ovulidae Fleming, 1822 are sometimes mistaken for seaslugs, especially when the shell is covered by the large colourful mantle. Let me quote Bill Rudman:
"One easy way to separate snails from slugs is to look for their eyes. If they are raised from the skin like this then they are a snail. If the eyes are embedded in the skin they are an opisthobranch."
How to cite:
Köhler, E. (2017), published 4 August 2017, Cuspivolva tigris (Yamamoto, 1971)
available from https://www.Philippine-Sea-Slugs.com/Look-alike/Ovulidae/Cuspivolva_formosa/Cuspivolva_tigris.htm