What is "lawrenceoceras"

Lawrenceoceras is a moderately curved, gently expanding bassleroceratid (Nautiloidia, Ellesmerocerida) from the Lower Ordovician of eastern North America. Septa dividing the chambers are close spaced; sutures straight, transverse; the siphuncle narrow, submarginal.

Lawrenceoceras is closely related to nautiloids such as Bassleroceras that gave rise to the Tarphycerida although it specifically may not be ancestral.