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n examining Plio-pleistocene turritellids from the Atlantic coastal plain we recently discovered a previously undescribed character state where the inner shell wall appears to have not been formed. This state along with a C1B2A3 apical ontogeny pattern for spiral sculpture appears to characterize a clade of turritellids now extirpated from Florida and the Atlantic coastal plain, but including several common eastern Pacific species. We designate Turritella gonostoma Valenciennes, 1832 as the type species for this genus and refer the eastern Pacific species Turritella banksii Gray in Reeve, 1849, Turritella broderipiana d’Orbigny, 1840, Turritella abrupta† Spieker, 1922 along with several western Atlantic fossil species to this genus. It is likely that numerous additional fossil and extant eastern Pacific turritellids should be referred to this genus. We designate this newly described character state as hollow newel morphology, based on an analogy to spiral staircases where the absence of a central supporting post is termed hollow (or open) newel construction. The hollow newel state also occurs in other gastropod taxa, though it appears to be rare among those with high spires. We also distinguish this state from other axis forms including a columella, an umbilicus, a hollow columella, and a partially resorbed columella.