The largest clade representing the Liliaceae, all previously included in Liliales, but including both the Calochortaceae and Liliaceae sensu Tamura. This redefined family, that became referred to as core Liliales, but corresponded to the emerging circumscription of the Angiosperm Phylogeny Group (1998). Phylogeny and APG system The 2009 revision of the Angiosperm Phylogeny Group system, APG III, places the order in the clade monocots. From the Dahlgren system of 1985 onwards, studies based mainly on morphology had identified the Asparagales as a distinct group, but had also included groups now located in Liliales, Pandanales and Zingiberales. Research in the 21st century has supported the monophyly of Asparagales, based on morphology, 18S rDNA, and other DNA sequences, although some phylogenetic reconstructions based on molecular data have suggested that Asparagales may be paraphyletic, with Orchidaceae separated from the rest. Within the monocots, Asparagales is the sister group of the commelinid clade. This cladogram shows the placement of Asparagales within the orders of Lilianae sensu Chase & Reveal (monocots) based on molecular phylogenetic evidence. The lilioid monocot orders are bracketed, namely Petrosaviales, Dioscoreales, Pandanales, Liliales and Asparagales. These constitute a paraphyletic assemblage, that is groups with a common ancestor that do not include all direct descendants (in this case commelinids as the sister group to Asparagales); to form a clade, all the groups joined by thick lines would need to be included. While Acorales and Alismatales have been collectively referred to as "alismatid monocots" (basal or early branching monocots), the remaining clades (lilioid and commelinid monocots) have been referred to as the "core monocots". The relationship between the orders (with the exception of the two sister orders) is pectinate, that is diverging in succession from the line that leads to the commelinids. Numbers indicate crown group (most recent common ancestor of the sampled species of the clade of interest) divergence times in mya (million years ago). Subdivision A phylogenetic tree for the Asparagales, generally to family level, but including groups which were recently and widely treated as families but which are now reduced to subfamily rank, is shown below. The tree shown above can be divided into a basal paraphyletic group, the 'lower Asparagales (asparagoids)', from Orchidaceae to Asphodelaceae, and a well-supported monophyletic group of 'core Asparagales' (higher asparagoids), comprising the two largest families, Amaryllidaceae sensu lato and Asparagaceae sensu lato. Two differences between these two groups (although with exceptions) are: the mode