The Wyoming Jurassic fossil Dentalium subquadratum Meek, 1860 is not a scaphopod but a serpulid worm tube

Since 1860, the record of Jurassic scaphopod mollusks has included Dentalium subquadratum from Wyoming. Restudy of F. B. Meek's type material indicates that the small, arcuate, tapered tubes lack definitive scaphopod characters. Instead, they resemble shells built by serpulid worms (Polychaeta) of the genus Hamulus , so D. subquadratum Meek, 1860 is here transferred to Hamulus subquadratus (Meek, 1860). Fieldwork indicates that Meek's syntype slab came from the Redwater Shale Member (Oxfordian) of the Sundance Formation, 14 mi (22.5 km) southwest of Casper, Wyoming.