Seymouria was an amphibian with many characteristics of reptiles.
Creature attributes[]
Physical appearance and biology[]
At 90 centimetres long, Seymouria resembled a reptile in its outward appearance. Though, surprisingly, it was not. Instead, it was a type of amphibian known as a reptiliomorph.
These creatures would begin there lives as tadpoles, much like amphibians do. But when they became adults, Seymouria's and other reptiliomorphs' bodies would sprout scales and gain the ability to conserve water, characteristics reminiscent of the reptiles that had descended from them in the Carboniferous.
A Seymouria, lurking in the shadows of the early Permian. (Reptile's Beginnings)
Male Seymouria had thicker skulls than the females. It is assumed that thickness of the skull in males was for use in mating rituals. So if two males would see a female they desire, they would begin to head butt each other until a victor is declared.
Seymouria's body was tan with brown splotches and its underbelly was white.
Behaviour and traits[]
Seymouria lived in semi-arid climates and spent large periods of time away from water thanks to the adaptations that they would gain upon reaching adulthood which allowed them to conserve water, much like a reptile. But females would return to the rivers and ponds they once spend their childhood in to lay eggs.
Its diet was purely carnivorous. As they went through their various larval stages their prey was worms and insects. When they became adults they still retained their taste for insects, but coherently widened their variety to smaller amphibians and other creatures.
Adult Seymouria also raided the nests of the megafauna at the time, such as Dimetrodon. This was a risky task, however, for they could end up on the menu of the parents of the eggs they wished to consume.
Seymouria also had a salt gland located in its nostrils that would excrete any excess salt gained by either the food it ate or from their environment.
In Walking with Monsters[]
Reptile's Beginnings[]
Seymouria makes a brief appearance in the episode when it prepares to raid the mother Dimetrodon's nest.
It attempts the act, but is soon killed by a male Dimetrodon who happened upon the nest too.
Behind the scenes[]
Seymouria was never named in the actual series; it was called 'an amphibian' instead. The actual name was revealed in The Complete Guide to Prehistoric Life instead.
List of appearances[]
Notes and references[]