Unlike later ceratopsians, however, it was a much smaller creature that lacked well-developed horns and retained some primitive traits not seen in later genera.
The head lacks horns, and the posterior end of the abdomen is forked.
Most other livestock species cannot easily be bred to lack horns naturally - for example: the polling gene in goats is closely tied to hermaphrodism.
Meanwhile, many other hoofed herbivores like camels, llamas, hippos and horses lack horns.
The most primitive horned dinosaur, Psittacosaurus (a ceratopsian) actually lacked horns and had only the beginning of a frill.
Trigonias was about 2.1 m (7 ft) long and, despite lacking horns, looked a lot like modern rhinos.
A newly hatched gold wyrmling appears similar to an adult, except that it lacks horns or tentacle whiskers.
Hutton states that modern photographs show the original cave art lacks horns, a human torso or any other significant detail on its upper half.
The female, referred to as the ewe, lacks horns.
This was a hairy, muscular entity who lacked horns but had large teeth.