The Strigoceratidae is a family in the ammonitid

Ammonitida

The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....

 superfamily Haplocerataceae

Haplocerataceae

Haplocerataceae is a superfamily of ammonoid cephalopods belonging to the Ammonitida that unites three families, the Strigoceratidae, Oppeliidae, and Haploceratidae, listed below....

, restricted to the lower Middle Jurassic

Middle Jurassic

The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....

, Bajocian stage, possibly derived from the Hammitoceratidae. The family was established and named by Buckman in 1924.

Description

The shells of the Strigoceratidae are compressed to oxyconic, with a narrow or minute umbilicus and simple or irregularly branched ribbing almost confined to the outer (ventral) half of the whorl sides. The sutures are moderately simple to complex, with a long umbilical lobe bearing a graded series of Auxiliaries.