Entemnotrochus adansonianus, common name Adanson's slit shell, is a species of sea snail, a marine gastropod mollusk in the family Pleurotomariidae.

This attractive species has a pale yellowish-fleshy color with numerous, irregular, reddish spots, sometimes vivid, sometimes more or less effaced.

The shell has a trochiform shape above, but is plano-convex beneath and concave in the middle.

The species has a (thin yellow in juvenile examples) operculum that completely seals the subquadrate aperture.

[4] A very few of these rare slit shells that reside at depths between 150 and 240 metres have been dredged and (crabbed examples) trapped.