[2][3][4] The scientific name Amiskwia sagittiformis derives from the Cree amiskwi, "beavertail", a name of various objects in Yoho National Park, and from the Latin sagitta ("arrow") and formis ("shape"), in reference to the general appearance of the animal.

The gut was straight, and ran from the mouth to the anus, which was located on the underside of the body near the caudal fin.

However, Amiskwia appears to lack the characteristic grasping spines and teeth of other Burgess fossil arrow worms.

The absence of spines could simply mean that the fossils represent young organisms — or that later chaetognath evolution involved paedomorphosis.

Vinther and Parry (2019) argued that Amiskwia was a stem-group chaetognath,[2] while Caron and Cheung (2019) suggested that the organism was a total group gnathiferan, based on the presence of gnathiferan-like jaws and ventral plates within the mouth.

Its precise affinity within this group is difficult to resolve, they suggested that if it fell in the stem lineage of any extant phylum then it would be a gnathostomulid.

[1] A 2022 study supported a stem-chaetognath interpretation, suggesting that gnathiferan-like jaws were lost in the ancestor of chaetognaths.