Most likely evolved from Clitendoceras, a narrow, slightly endogastric genus intermediate in form between straight shelled Proendoceras and the bulkier Piloceratidae.

Found in shallow carbonate marine sediments of Demingian through the Cassinian age, (essentially Arenigian, = early Middle -Upper Canadian) .

With the exception of Humeoceras, found in the middle Silurian, pilocerid genera are limited to the Lower Ordovician (Canadian in North America).

The general shape of the pilocerid shell precludes an ambush predator lying in wait on the sea floor, or a stealthful hunter drifting through the water.

Pilocerid genera include the strongly curved Piloceras, Bisonoceras with its hooked bison horn shape, nearly straight Allopiloceras, Dartonoceras, and internally complex Cassinoceras.