The animal is segmented, and looks somewhat like a bloated caterpillar with a few spines added on — including six finger-like projections around the mouth and two grasping limbs on the "head".

[2] A pair of legs marks the posterior end of the body, unlike in onychophorans where the anus projects posteriad; this may be an adaptation to the terrestrial habit.

[4] Aysheaia is a lobopodian, an extinct phylum of marine animals that are similar to modern terrestrial Onychophora (velvet worms).

A. prolata was described as a separate species from the similarly-aged Wheeler Shale Formation of Utah but in fact represents the frontal appendage of a Stanleycaris-like radiodont.

[2] In the 1970s, Whittington undertook a thorough redescription,[1] and associated Aysheaia with the tardigrade lineage concept promoted a couple of years earlier by Delle Cave and Simonetta,[10][3] and first proposed in 1958.

These were differentiated from Euonychophora (the crown group) by the number of lobopod legs and claws, the unusual head appendages, the absence of eyes, jaws, antennae and slime glands, the morphology of the rear of the body, and the terminal mouth.