A new species of turritelline gastropod from a turritelline-dominated limestone in the Paleocene of North Carolina

Abstract

Turritelline Gastropods (family Turritellidae, subfamily Turritellinae; sensu Marwick, 1957) are common components of many Cretaceous to Recent benthic marine assemblages worldwide. They are frequently the dominant or even the sole macrofossil in such assemblages (Allmon, 1988), termed “turritelline- dominated assemblages” (TDAs; Allmon and Knight, 1993). They are defined as macrofaunal assemblages in which turritelline gastropods: 1) comprise either at least 20% of the total actual or estimated biomass or at least 20% of the macroscopic individuals in the assemblage, and 2) are at least twice as abundant as any other macroscopic species in the assemblage (Allmon, 2007). TDAs have been widely reported from siliciclastic and carbonate sediments of the U.S. Gulf and Atlantic Coastal Plains, but turritelline-dominated limestones (sometimes referred to as “turritella limestone” or “turritella rock”) appear to be limited to the Cretaceous and Paleogene (Allmon and Knight, 1993; Allmon, 2007; Allmon and Cohen, 2007).