The Sinoceratidae is a family of orthoceroids, named for the genus Sinoceras

Sinoceras

Sinoceras is an extinct nautilid genus from China included in the family Orthoceratidae that lived during the period from perhaps the middle Ordovician to as late as perhaps the Devonian....

, both by Shimizu and Obata 1935, and equivalent to the Michelinoceratinae Flower, 1945.

The Sinoceratidae are characterized by relatively long septal necks in the siphuncle, reaching as much as half way between septa in the chambers; sparse cameral deposits and apparently none within the siphuncle.

The inclusion of the Sinoceratidae in some classifications in the Lituitida instead of the Orthocerida is based in part on the idea that the Lituitidae

Lituitidae

The Lituitidae is a family of evolved tarphycerids characterized by a long orthoconic section that follows a coiled juvenile portion at the apex, along with a generally tubular siphuncle, which like that of the barrandeocerids is composed of thin connecting rings.-Taxonomic Position:Flower and...

 are included in the Orthocerida rather than as originally perceived in the Tarphycerida

Tarphycerida

The Tarphycerida were the first of the coiled cephalopods. They are found in marine sediments from the Lower Ordovician to the Middle Devonian. Some like Aphetoceras and Estonioceras are loosely coiled, gyroconic, others like Campbelloceras, Tarphyceras, and Trocholites are tightly coiled, but...

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References

• Rousseau H Flower, 1962. Notes on the Michelinoceratida. Memoir 10, Part II. New Mexico Bureau of Mines and Mineral Resources. Socorro NM.
• Walter C. Sweet, 1964. Nautiloidea-Orthocerida. Treatise on Invertebrate Paleontology, Part K. Geol. Soc. of America and Univ. Kansas Press.