Liliidae's a botanical name at the rank of subclass. of the subclass will vary with the being used (there're many such systems); the only requirement being that it includes the family Liliaceae. Liliidae in Takhtajan system The Takhtajan system treats this as one of six subclasses within class Liliopsida (= monocotyledons). This subclass consists of: subclass Liliidae : superorder Lilianae :: order Melanthiales :: order Colchicales :: order Trilliales :: order Liliales :: order Alstroemer… (More on Liliidae)