We want to get summary stats about the Kew herbarium by WCVP taxonomy at family level, using the herbarium data in GBIF.
Any field that is searchable in the GBIF data portal is also eligible for faceting, eg it is possible to get a summary report of the numbers of records in each country using this API call:
Though each occurrence record has a family field, it is not used for searching so cannot be used to facet.