The Valcouroceratidae is an oncocerid

Oncocerida

The Oncocerida comprise a diverse group of generally small nautiloid cephalopods known from the Middle Ordovician to the Mississippian ,in which the connecting rings are thin and siphuncle segments are variably expanded...

 family from the middle and upper Ordovician

Ordovician

The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...

, mainly of North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, consisting of genera characterized by exogastricly curved cyrtoconic and breviconic shells that change ontogeneticially from compressed to depressed or subtriangular and in which the siphuncle in ventral and actinosiphonate.

Generic Composition

The Valcouroceratidae comprizes 8 genera, three of which, Valcouroceras, Augustoceras, and Actinomorpha were named by Flower in 1943 and 1946 and five of which,Fayettoceras, Kindleoceras, Manitoulinoceras, Minganoceras, and Staufferoceras were named previously by Foeste between 1924 and 1938. Flower established the Family Valcouroceratidae in 1945, based on Valcouroceras which he named in 1943. All 8 genera were included as late as 1950 where they rest today.

References

• Flower, R. H. and Kummel B, 1950; A Classification of the Nautiloidea; Journal of Paleontology V24 n.5 Sept 1950
• Sweet, W. C. 1964; Nautiloidea-Oncocerida, in the Treatise on Invertebrate Paleontology; Geological Society of America and University of Kansas Press.
• Valcouroceratidae -Paleobio db