new term request: styliform element

I want to annotate this new species description: A bizarre Jurassic maniraptoran theropod with preserved evidence of membranous wings

They identify a novel skeletal element:

In particular, the rod-like bone of Yi is strikingly similar to the enlarged carpally situated element seen in some petauristines, including the Japanese giant flying squirrel Petaurista leucogenys. For convenience, we adopt ‘styliform element’ as a general term for unjointed, rod-like bony or cartilaginous structures that extend from distal limb joints in tetrapods.

Uberon currently has only 'styliform cartilage'. Two questions: Can we add the corresponding 'element' term? Can the current term be expanded to more of a structural concept, or should there be a separate term for theropodan styliform elements? Clearly it's not homologous to the mammalian structure.

cc @alex-dececchi