They use unique appendages of the propodium (front part of the foot) to deploy mucus nets which capture suspended particles from the backwash on sandy beaches of the tropical eastern Pacific.

[1] Olivella semistriata is a swash-surfer; the snails use their expanded foot as an underwater sail to follow the tidal movement of the backwash zone in which they feed.

The shell is smooth and shiny except for the upper (= posterior) half of the body whorl which carries dense longitudinal grooves, or striae (hence the name semistriata).

The fasciolar band (= a distinctly structured portion of the shell around the siphonal notch) is brownish gray to white, and so is the apex in most individuals.

Some Olivella semistriata populations at sheltered locations with low wave energy consist entirely of dwarfish animals that hardly reach 10 mm shell length.

[1] This explains why small shells were described originally as a separate species, Oliva attenuata, by Reeve (1851),[8] an author who evidently was familiar with the typical, larger O. semistriata.