Initially proposed as a deuterostome, which would have made it the oldest known species of this superphylum,[4][5] it has since been determined to belong to a protostome group called the ecdysozoans.

[2][7] A 2024 paper suggested it may instead be the non-feeding larva of a scalidophoran, tentatively linking it to Eokinorhynchus due to their shared bilateral sclerites.

[4] However, the strong folding found in the fossils makes this conclusion tentative,[2] with Simon Conway Morris, one of the British scientists involved in its discovery, admitting the possibility that the team simply has not spotted it.

[3] Below is a simplified phylogenetic tree based on this classification, with dashed lines showing uncertain placements: Deuterostomia Spiralia Saccorhytus coronarius?

Scalidophora Nematoida Panarthropoda Saccorhytus most likely lived a meiofaunal lifestyle, with its body plan suited for an interstitial habitat, such as its thick but flexible cuticle providing protection and allowing it to wriggle through grains of sand.