The living animal reached a couple of centimetres in height, and bore a loose scleritome of ovoid sclerites.

[3] A more recent alternative proposal suggested a relationship with the Cambroernida, a group of early deuterostomes.

[5] A comprehensive 2013 study of around 400 new specimens provided stronger support for a lophophorate affinity, specifically allied with the entoprocts.

[2] The clear presence of a U-shaped gut in the new specimens contradicts placement among the cnidarians, while the lack of bifurcation in the crown of tentacles makes affinity with the deuterostomes unlikely.

[6] A recent review of echinoderm origins again refuted the placement of Cotyledion with that group, agreeing with its identity as a stem entoproct.