Sinotitinae is one of three

subfamilies In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

of the

Dimeroceratidae Dimeroceratidae is one of three families in the Dimeroceratoidea, a goniatid superfamily included in the Ammonoidea; extinct shelled cephalopods with adorally convex septa and usually narrow ventro-marginal siphuncles. The family Dimeroceratidae ...

, a member of the

Goniatitida Goniatids, informally goniatites, are Ammonoidea, ammonoid cephalopods that form the order Goniatitida, derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago (around Eifelian stage). Goniatites (goniat ...

, an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

order of

ammonoid Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

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.

References

Sinotitinae entry on the Paleobiology Database
5/26/12 Dimeroceratidae Late Devonian first appearances Late Devonian animals Late Devonian extinctions {{Goniatitida-stub