Read story Walking With Series Creature Bios - Cephalaspis

Cephalaspis

The Silurian had one of the first fish to grow over an inch long. That fish was the jawless Cephalaspis. Sharing its environment with predatory arthropods like Brontoscorpio, Cephalaspis had to adapt some unique defenses to keep itself alive.

Basic Info

Meaning of name: Cephalaspis means "head shield".

Time of existence: Despite being shown in the Silurian period, Cephalaspis lived in the early Devonian, 415 million to 398 million years ago.

Diet: Cephalaspis had no jaws, and could not bite, therefore, they were bottom feeders and only ate worms, algae, and small shellfish, using water pressure to suck them into its mouth.

Threats: Cephalaspis was the primary prey of the giant scorpion Brontoscorpio. They were also most likely eaten by another eurypterid called Pterygotus.

Length: Cephalaspis was only about 9 inches long.

A Cephalaspis burying itself in the sand

Attributes: Cephalaspis had a defensive head shield that had sensors on it. These sensors created an electrical field that would detect nearby predators. However, this was also a risky evolution, as it caused Cephalaspis to tire quickly. Unlike other animals at this time, they were also able to use memory with their primitive complex brains. Cephalaspis could also briefly slide across land.

Appearances in the Walking With... series

Walking with Monsters

Episode 1-Water Dwellers

Cephalaspis appears twice in the intro of the episode. It briefly appears fleeing from a hungry Brontoscorpio, and next appears while evolving into an amphibian called Hynerpoten. Cephalaspis first appears in the actual episode when Haikouicthys evolves into it. In the Silurian segment of the episode, Cephalaspis is the primary focus, and is first seen searching for food on the floor. However, she is interrupted by a Brontoscorpio, which attempts to catch her, though she successfully escapes. Some Cephalaspis are also seen swimming behind a shoal of Brontoscorpio, and a school is seen swimming near some orthocones. They also are briefly seen searching for food. However, the school begins to flee from a hungry Brontoscorpio, who attempts to attack the female. However, she senses him due to the sensors on her head, and is able to get a headstart as the scorpion attempts to catch her. However, due to her headgear, she cannot swim fast for long, and must rest frequently, which puts her in danger of being caught by the scorpion. However, after picking up another set of vibrations, she quickly changes paths, and narrowly avoids being the next meal of both Brontoscorpio and a giant eurypterid. We then cut to the breeding season, where a massive convoy of Cephalaspis are swimming to fresh water to lay their eggs, much like modern day salmon. It is also explained that they are one of the first animals to actually use memory, as they have one of the first complex brains, and use landmarks to remember the path. Eventually, the Cephalaspis are able to find the spawning pool where they were born. However, despite being exhausted, they are forced to cross a ridge of rock. The fish begin to push themselves across the rock, and reach the pool where they lay their eggs.

A Cephalaspis crossing a rock ridge

However, many of the fish are not so lucky, as a group of Brontoscorpio arrive and begin to attack the Cephalaspis to eat them. Despite this, most of the fish successfully lay their eggs, and begin to make their way back to the sea. However, Cephalaspis had a different destiny in store for them, as their gills evolved into jaws, and their fins began to change into limbs as their muscles strengthened. Eventually, Cephalaspis would evolve into the amphibian Hynerpoten.