Trachyceratidae


The Trachyceratidae is an extinct family of ceratitid ammonoid cephalopods.
The Trachyceratidae makes up part of the superfamily Clydonitaceae along with such families as the Clydonitidae and Arpaditidae. The Clydonitaceae is also known by the junior synonym Trachycerataceae.

Description

Trachyceratid shells are more or less involute and highly ornamented. They have their whorl sides covered with flexious ribs that are usually tuberculate. The venters generally have a median furrow bordered by rows of tubercles or continuous keels.

Selected genera

Fossils of Trachyceratidae are found in marine strata from the Devonianto the Triassic . Fossils are known from many localities in Afghanistan, Canada, China, Europe, India, Japan, the Russian Federation, Slovenia, Spain, Switzerland, Thailand, Ikraine and United States.