Tritia nitida ground open to reveal interior of spire.

The siphonal canal remains as a deep groove (1) on the spiral columella for its entire length to the apex of the shell.

Rolan and Luque (1994) state that the exterior and interior of T. nitida shells in Ria de Vigo are violet, and Jeffreys (1867) states that its shell is purplish, with brighter purple lines (see fig. 57) than on T. reticulata. But, the presence and intensity of purple varies greatly from intense (see fig. 59) to absent or, as in the aperture of the beachworn shell above, faded. Purplish-brown has survived within the spire which was unexposed to light until opened.

Blackwater, Essex, England, September 2019, leg. S.Taylor.