What is "sinotitinae"

Sinotitinae is one of three subfamilies of the Dimeroceratidae, a member of the Goniatitida, an extinctorder of ammonoid cephalopods from the Paleozoic.

The two comprised genera, Sinutites and Sunites have broad, crescent shaped whorl sections, but one, Sinutites has a dorsal siphuncle while in the other, Sunites the siphuncle is ventral.