Threehorn

From Land Before Time Wiki

This is the type of Dinosaur that Cera's Dad Topsy is as well as Cera, Tria and Tricia. They are so named due to their having 3 horns, a small one just behind their nose and two on their heads that point forward and slightly to one side.

This includes such dinosaurs as:

Triceratops
Chasmosaurus

[edit] Gallery

Screenshots of Threehorns

Group shot, 1st movie	Cera's Dad	Cera, in The Land Before Time X: The Great Longneck Migration	Cera, in the TV series.
Dinah & Dana.	Tria	Tricia