Trilliaceae


Trilliaceae was the botanical name of a family of flowering plants. The family has been recognised as distinct since 1846 when it was recognized; this table for a summarizes the placement of these taxa. The family has been recognized by taxonomists such as Takhtajan, Dahlgren, Thorne, and Watson & Dallwitz; other taxonomists have considered these plants to belong to the family Liliaceae. The APG IV system, of 2016, does not recognize such a family either and assigns the plants involved to family Melanthiaceae, tribe Parideae. One problem with this recognition is the lack of morphological synapomorphies for the family Melanthiaceae; this chart provides a summary of the characters in each of the major groups.
Nevertheless, some taxonomists still recognize a separate family Trilliaceae. The most important genus in North America is Trillium, and the taxonomy of that genus has always been controversial. To paraphrase what Steven Elliott wrote of the genus Trillium in 1817,
A recent treatment stated that the family Trilliaceae, which exhibits an arcto-tertiary distribution, comprises six genera. Three of these exhibit a wide distribution:
Three are monotypic, endemic genera:
Within Melanthiaceae, these are consolidated into three genera;
;Parideae