Rotularia

Rotularia is an extinct genus of planispirally coiled fossil polychaete worms in the family Serpulidae. Owing to the gastropod-like shape of Rotularia, many authors in the past interpreted this genus as being sea snails in the family Vermetidae.^[1] Like many other members from Vermetidae the Rotularia is approximately 5 inches in length. This is an estimate from the 151 confirmed fossil discoveries.

Rotularia Temporal range: Kimmeridgian–Eocene PreꞒ Ꞓ O S D C P T J K Pg N (Jäger, 2004)
Rotularia concava fossil
Scientific classification
Kingdom:	Animalia
Phylum:	Annelida
Clade:	Pleistoannelida
Clade:	Sedentaria
Order:	Sabellida
Family:	Serpulidae
Genus:	†Rotularia Defrance, 1827

Description

All Rotularia species were cemented to the substrate during their earliest growth stage, but they became detached shortly after the formation of the first whorls (Savazzi, 1995).^[2] Rotularia originates in shallow marine environments.^[3] Their tubes have two layers with different microstructure (Vinn, 2008). This genus is known from the early Kimmeridgian to Late Eocene (Jäger, 2004).