Table 2.

Table 2: Metadata elements additionally added to the DwC-MIxS mapping document to capture the syntactic mapping between keys. Please see an example of how these keys were used in the mapping in the Suppl. material 1 Section 1.

Element ID	Description	TSV/RDF Example
syntax_predicate_id	The ID of the predicate or relation that relates the syntax of the subject and object of this match.	skos:relatedMatch
syntax_comment	Free text field containing either curator notes or text generated by a tool providing additional informative information on the syntactic mapping.	The subject expects a verbatim input (so anything really), while the object expects a {float} {unit} entry.