Symbolism of Hallucgenia in Attack on Titan

This is relates to the series Attack on Titan so bear with me.

In the series Attack on Titan, Hallucigenia was introduced as “the source of all life” and was the source of both the Power of the Titans.

This is a question to the paleontology experts who are familiar with the Attack on Titan series: what kind of fossil or prehistoric symbolism wouls Hallucigenia have that correlates with the Attack on Titan series? Again pls bear with me here.