Roseaplagis caelatus is a species of small sea snail in the family Trochidae, the top shells.

[1] It is smaller than Cantharidus sanguineus (height: 5.5 mm, diameter 4.5 mm) but it is more deeply ribbed and its grooves are wider.

Sometimes they are obsoletely granose through being crossed by growth lines.

The columella shows a slight swelling in the middle.

[3] This marine species is endemic to New Zealand and occurs off the Foveaux Straits; Port Pegasus, Stewart Island; Snares and Bounty Islands The former subspecies have been named: