The date on which the subject was determined as representing the Taxon.

Recommended best practice is to use a date that conforms to ISO 8601-1:2019.

`1963-03-08T14:07-0600` (8 Mar 1963 at 2:07pm in the time zone six hours earlier than UTC). `2009-02-20T08:40Z` (20 February 2009 8:40am UTC). `2018-08-29T15:19` (3:19pm local time on 29 August 2018). `1809-02-12` (some time during 12 February 1809). `1906-06` (some time in June 1906). `1971` (some time in the year 1971). `2007-03-01T13:00:00Z/2008-05-11T15:30:00Z` (some time during the interval between 1 March 2007 1pm UTC and 11 May 2008 3:30pm UTC). `1900/1909` (some time during the interval between the beginning of the year 1900 and the end of the year 1909). `2007-11-13/15` (some time in the interval between 13 November 2007 and 15 November 2007).

http://rs.tdwg.org/dwc/terms/