Common name : sundial shellor staircase shells

Aspect : flattened, low-spired, planispiral (coiled in a single plane); discoidal or conical in shape, with a deep umbilicus narrowing inward, often with a thick lateral bead; sculpted with strong ribs, prominent spiral ridges creating a "staircase" or stepped profile often highly geometric; large and rounded aperture with a thickened outer lip; coloration usually white, cream, or pale with darker spiral bands or patterns; horny operculum; their unique architectural appearance gives them the name architectonicid (“builder-like”)

Feeding : predators (sea anemones, sessile cnidarians, zoanthids, corals)

Environment : worldwide in tropical and subtropical regions (especially the Indo-Pacific) on sandy or muddy sediments often found on coral reefs, seagrass beds, or near anemone colonies; in intertidal to shallow subtidal zones (typically 0–30 m depth) down to several hundred meters